eChapters

ABSTRACT

Airborne geophysical methods are presently used all over the world to support mineral exploration by providing basic geological information to supplement existing geological maps. The popularity of airborne geophysics is due to its lower cost for unit of area surveyed, as compared to all other methods of exploration. South India has been extensively covered by high altitude regional aeromagnetic surveys jointly by GSI and NRSA, low altitude multi-sensor surveys by foreign agencies, viz. M/s. Parsons, U.S.A. (Operation Hard rock Project) and BRGM/CGG, France, on contractual basis for GSI and by GSI (Twin Otter surveys) in selected belts and low altitude aeromagnetic surveys by NGRI in the SW part of the Cuddapah basin and the adjoining crystallines. Integrated studies of geophysical (airborne and ground), geological and remote sensing data have greatly helped not only in augmenting the geological knowledge of the region, but also in identifying several metallic prospects/ deposits. The present paper illustrates several case studies in demonstrating the utility of aerogeophysical data in geological mapping (identifying lithologies, structures and basement characteristics) and locating metallic prospects/ deposits.

ABSTRACT

With the increasing use of ground water for various activities, the fast decline in groundwater takes place. In order to prevent the aquifers from fast depletion, the ground water recharge is necessary. This study attempts to identify the favourable areas for groundwater recharge and suggest suitable recharge structures toaugment the aquifer system of the study area using Remote Sensing and GIS. The various thematic maps such as Geomorphology, Geology and lineaments, Soil, Slope, Land use, Drainage, Runoff, Depth to weathered zone, Groundwater level fluctuation and Water quality are used in the analysis. The favourable areas for groundwater recharge have been categorized into highly favourable, moderately favourable, less favourable and poor. To delineate areas favourable for recharge zone various themes are interpreted. The identification of ground water recharge zones for the study area is useful for improvement of water quality, quantity and better augmentation & management of Groundwater recharge.

ABSTRACT

The disposal of industrial effluents in rivers causes groundwater contamination. It is necessary to assess how these contaminants are likely to migrate in the groundwater system. In the present study, an attempt is made to study the migration of contaminants in the groundwater of Palar River basin in Tamil Nadu. Simulation of the contaminants was carried out by using numerical methods. The finite difference computer code MODFLOW (Modular 3-d finite difference flow) and MT3D (Mass transport 3-d) with Groundwater Modelling System (GMS) as pre and post processor was used to simulate the groundwater flow and transport in this study. The simulation was done in transient state for a time period of one year. It predicted the migration of plume of chlorides in groundwater. The changes in the distance and concentration rate of chlorides are identified for a particular period. Modelling provides a useful basis for contaminant transport studies, as well as in the evaluation of the hydrogeologic parameters relevant in the context of the transport problem.

ABSTRACT

Kadayampatty Panchayat Union is situated in the northern part of Salem district, adjoining the Dharmapuri district of Tamil nadu. It lies between the latitudes 11°45’ -12°N and longitudes 78° -78°15’E in the Toposheet No.58I/1. The study area mainly consists of the rocks of late Precambrian age that are characterised by migmatitic gneisses, Ultramafic rocks and Pyroxenite. In this study an attempt has been made for demarcating groundwater techniques. Resistivity of rock formation varies over a wide range, depending on the material density, porosity, pore size and shape, water content, quality and temperature. In relatively porous, highly jointed and fractured formation the resistivity is controlled more by water content and quality with in the formation then by the rock resistivity. For demarcating groundwater potential zones in the Kadayampatty Panchayat Union water table analysis and ten Vertical Electrical Sounding (VES) followed by Schlumberger electrode configuration were carried out. The maximum depth of investigation was 150mts. The electrode spreads were generally in steps of five meters interval up to 50 mts and 10 mts interval up to 150 mts. VES location were selected with in the study area with respect to their topographic features. Inverslope method proposed by Sankaranarayan (1974) et.al has been used to evaluate the geoelectrical parameters in order to demarcate to potential groundwater zones for new dug well and bore well locations. The lithological interpretation reveals that the presence of a maximum of five geoelectrical formations in the study area viz. Topsoil, weathered zone, fissure and fractured zone, fracture basement and fresh basement. Howevers all five formations do not occur throughout the study area, as the maximum and minimum of geoelectric layers are four and three respectively. Similarly a thin geoelectric layer was observed in some places also. The comparatively high resistivity values with corresponding high values of thickness are indicative of a wide stretch of unweathered and unfractured fresh rock layers. A highly weathered (saturated) basement is indicated by the extremely low resistivity value. The depth to the fresh basement varies.

ABSTRACT

Identification and mapping of fractures/lineaments and hydrogeomorphic units is prerequisite for undertaking ground water exploration and development in any terrain. Remote sensing and GIS techniques have been used for ground water potential mapping in Theni District. The study area has been divided into various geomorphic units based on visual interpretation of LISS III and PAN merged data in false colour composite on 1:50,000 scale. Ground water potential of each of the geomorphic units was assessed and correlated with geology, structure and recharge factors prevailing in the Theni District.

ABSTRACT

Trace Elements were analysed from water samples collected from bore wells from block 2, 5, 14, 26 and 29 at Neyveli Township. Lead Concentration has crossed the limit of ISI standard prescribed for drinking which is 0.100 ppm. Lead concentration in the order of 0.082 ppm at block 5 and 0.11 ppm in block 29 were observed. Cadmium concentration has also crossed the limit of ISI (0.010 ppm) for drinking purpose, which is 0.02 ppm in block 26. Chromium concentration has also crossed the permissible limit of ISI standards (0.05 ppm) for drinking, which is 0.098 ppm in Block 14.

The above elements when compared with ISI standards for drinking water have shown a slight increase in concentration of lead, cadmium & chromium. Concentration of lead in Neyveli basin may be attributed to basement geochemical sources influenced by physical and chemical weathering. High concentration of chromium and cadmium in the aquifer may be due to anthropogenic activity probably from effluents of closed briqueting & carbonization plant, which is due south of block 14.

ABSTRACT

Mecheri Panchayat union lies in the northwestern part of Salem district and adjascent to Dharmapuri district of Tamil Nadu. It lies between the latitudes 11°43’ -12° and longitudes 77° 48’ -78° 03’ of Toposheet No. 58 E/13 of scale 1:50,000 published by survey of India in 1973. Mecheri Panchayat union covers a total area of about 177.6 Sq.Km with a population nearly 1 lakh, live in 150 hamlets. Groundwater is the only replenshable nature resources available to man. The use of groundwater has been growing steadily over the years for domestic, agricultural and industrial purposes. Hydrogeochemical study is a dynamic process undergoing constant change in space and time. In unconfined aquifers, the change likely to be quite rapid and cyclic in nature with respect to the mode of recharge and discharge and related to the nature of host aquifer. In this study an attempt has been made for understanding the chemical quality of groundwater in theunconfined aquifer of Mecheri union. Groundwater samples have been collected from 10 representative dug wells lying in the Mecheri union during December 2004 and analysed by the standard procedures of water analyses. It is essential in determining its usefulness for domestic, industrial and agricultural purposes. Presentation of Geochemical data in the form of graphical charts such as Collin’s bar, Stiff’s polygon diagram, Pie diagram, Piper tri linear diagram, USSL classification and thematical maps were prepared for recognizing various hydrogeochemical types in the Mecheri union. Deleterious effects of fluoride on the human beings are well known. Fluoride are known to be beneficial, when present in concentration ranging from 0.5 ppm to 1.2 ppm. But when it exceeds the limit 1.2 ppm it is found to cause fluorosis. Dental, skeletal and non-skeletal fluorosis may be caused depending upon the concentration of fluorides in drinking water. The main source of drinking water for the majority of people of Mecheri union is groundwater obtained through dug and bore wells. The analysis of groundwater samples showing high (> 1.5 ppm) fluorite content observed in the following villages, viz Mallikundam, Kuttapatti Aranganur, Banapuram, Sathappadi, Mecheri town, Virudasampatti and Amaram.

ABSTRACT

The study narrates the importance of occurrence of groundwater in the crystalline terrain and its yield in different lithologies. In general, yield of well in the crystalline terrain of the study area is low. Average or mean yields for groups of wells in various regions are most commonly between 7 to 20 gpm: The smallest yields are encountered in granulitic terrain and this may be due to fracture closing rapidly with depth. The jointed and weathered geneses yield small but steady supply of water at shallow depth. Chemical quality of the groundwater from this terrain is generally satisfactory for most purposes.

ABSTRACT

The estimation of the water requirement of crop is one of the basic needs for crop planning on the farm and for the planning of any irrigation project. Water requirements of crops include the losses due to Evapotranspiration (ET) plus the losses during the application of irrigation water (unavailable losses) and the quantity of water required for special operations such as transplanting and leaching of excess salts for crop growth. It is therefore necessary to estimate the ET and Crop Water Requirement (CWR) for the efficient use of water and increased crop production. In the present study, meteorological data were collected and the crop ET (ETc) and the CWR were estimated using FAO Penmann – Monteith method for the cropping pattern of the Buthangudy canal command area situated at a distance of 2Km from the popular village Sethiathope, Cuddalore district, of Tamil Nadu, India, which is located in between the Kumbhakonam – Chennai NH – 45 main road. The methodology combines the capability of GIS and CWR to produce maps showing spatial distribution of water resources over large areas.

ABSTRACT

An integrated geological, hydrogeological and geophysical analyses have been made to delineate groundwater potential zones in the Omalur Panchayat Union, Salem district, Tamilnadu. Sarabanga river is a major stream originating from western slope of Shevaroy hills. The tributaries are essentially consequent types. They are ephemeral in nature and the flow is restricted to the monsoon seasons. The flows of the streams are controlled by lineaments. Low drainage density, stream frequency and low relief indicate relatively high recharges and low runoff. The main lithological units are unclassified gneiss, grantite, charnockite, younger ultramafic rocks and recent alluvium. Ten vertical electrical soundings (VES) were carried out using Schlumberger electrode configuration. The maximum depth of investigation was 150meters when the electrode spread was generally in steps of 5 meters interval up to 50 meters and 10 meter intervals up to 150 meters. The field data were interpreted with the help of inverse slope method. Inverse slope field graphs reveal that in most of the locations, the aquifer consistsof five layers and third and fourth layersare normally weathered and highly fractured layers. These layers have attained a thickness range from 10 to 60 meters at the Tholasampatti, Sikkampatti, Pagalpatti and Sakkaraichettipatti. Correlation between the result of the VES data and the well lithology will be very useful in evolving ground water potential zones. Bore wells, dug wells in this area are normally sinking type wells. It will receive water only from the weathered, fissured and fractured zones which act as a favorable layers zones for tapping groundwater.

ABSTRACT

Ground water is an important source of water supply throughout the world for irrigation, industries, municipalities and rural homes and the dependence of an Indian village is on its water source only. The quality of water is as important as its quality. The quality required of a groundwater supply depends on its purpose such as drinking or agricultural or industries. To establish quality criteria, measures of chemical, physical, biological constituents must be specified as well as standard methods for reporting and comparing results of water analysis .For that a case study is to be made. Cuddalore district is a rapidly growing urbanized industrial area and lies at the east coast of Tamil Nadu in India. It mainly depends on the ground water. Water quality data for the observation wells from the year 1989 to 1999 were collected and spatial distribution of the groundwater quality is analysed using geographic information system. The important factors such as pH, Chloride shows higher level and generally occur in the central belt of the study area which is rich in mineral wealth. Compared to the eastern half the western half shows better quality of water. From the analysis, 80% of the study area is suitable for agricultural purpose and 75% of the study area is suitable for domestic and drinking purpose.

ABSTRACT

The chemical characteristics of the groundwater in and around the Valapadi taluk of Salem district have been studied to evaluate the suitability of water for domestic and irrigation uses. Twenty three groundwater samples representing the shallow and deep aquifer of the area were collected and analyzed for pH, TDS, Ca, Mg, Na, K, HCO3, CO3, SO4 and Cl. It is observed that the quality of the groundwater is suitable for domestic use with some exception. The observed high quantity of Cl, SO4 and Mg at some places require immediate attention and detailed study. The value of EC and SAR indicate good to medium q of water for irrigation.

ABSTRACT

Hydrogeochemistry of a region is a reflection of hydrodynamic process, composition of lithology and physical constraints. The water chemistry is the resultant of all biogeochemical processes and reactions, which have acted on water from the moment it has condensed in atmosphere till the time it is discharged. A case study has been carried out in a varied lithological terrain with Archean, Alluvium and Tertiary rocks to unravel the hydrogeochemical process. A geochemical model relays the distribution of mineral species in the groundwater. Geochemical modeling WATEQ4F has been carried out for pre-monsoon and monsoon period of various litho units in Gadilam river basin, Tamilnadu to find out the disequilibrium indices of carbonate (calcite, dolomite, magnesite and aragonite) and sulfate minerals (anhydrite and gypsum). The result of the model reveals that carbonate minerals show the over saturation state in monsoon period and the Sulfate minerals exhibit under saturation state in both the seasons.

ABSTRACT

Microalgae in general and Cyanobacteria in particular are considered to be ideal biotechnological tools for their importance in the production of food, feed, fuel, fertilizers, fine chemicals and pharmaceuticals and their role in pollution abatement. So far, only 20 strains of microalgae have been cultivated for industrial purposes. To make use of more such organisms, it is essential to first identify their biodiversity in the naturally occurring populations and establish their germplasm for further characterization. With this in view, a detailed survey was made to study the biodiversity of Cyanobacteria in the Veeranam lake soil microflora in the Cuddalore district of Tamil Nadu. Influence of physico-chemical parameters habitat preferences of these soil microalgae, and their light and Electron microscopic features have been documented. The selected species of Cyanophyceae were subjected to energy dispersive spectroscopic analysis (EDS). They were found to accumulate different elements such as Zn, P, Mg, Ca, Mn, S and N. Thus these observations would determine the chemical dialogue between the cell structures and role of the elements. Further, it gives the clue about the soil microflora growth requirements.

ABSTRACT

The sources of fluoride in groundwater are minerals like fluorite, apatite, mica, amphiboles,cryolite and fluor.spar. The undue concentration of fluoride greater than 1 mg/l has befallen a major toxicological and geoenvironmental issue in India. Excess of fluoride in groundwater causes skeletal and dental fluorisis. The study area forms part of Salem district with records of endemic fluorisis. To decipher process and chemistry of fluoride, a total of 46 groundwater samples were collected from major litho units of the study area (Peninsular gneiss and Charnockite) and analyzed for fluoride using standard procedures for two seasons viz. pre and post monsoon. In pre-monsoon, maximum and minimum fluoride in Peninsular gneiss and charnockite were ranging from 2.85 to 0.4 mg/l and 4.02 to 0.37 mg/l respectively. The coresspnding figures in post monsoon ranges from 2.84 to 0.32 mg/l and 1.91to 0.37 mg/l respectively. Higher concentration was noted in charnockite folowed by peninsular gneiss in pre monsoon and the effect of dilution was well noted in post monsoon season. Statistical analysis undercovers the relationship of fluoride minerals with other ions. Modeling results represent the leaching of fluoride minerals and their variation along with seasons.

ABSTRACT

The occurrence of fluoride more than permissible limit has been observed in ground water near Danishpet, Rajammannar Colony, Vayapurikombai, Melkombai, Umbilikampatty, Andikottai HC in Kadyampatty area, Salem district. Fluoride reaches to a maximum of 2.8 mg/l. Fluoride concentrations in ground water in various areas are as follows: Danishpet(2.0mg/l), Rajammannar Colony (2.8mg/l), Vayapurikombai (2.4 mg/l), Melkombai (2.4mg/l), Umbilikampatty (2.2 mg/l), and Andikottai HC (2 mg/l).. Granite gneiss and associated secondary vein filling minerals may be the source of high fluoride in ground water. The high concentration of Fluoride in ground water has led to human health hazard in the form of dental and skeletal deformation in the parts of Danishpet, Rajammar Colony, Vayapurikombai, Melkombai, Umbilikampatti and Andikottai HC villages.

ABSTRACT

A watershed is a topographically delineated area that is drained by a stream system, i.e. the total land area above some point on a stream or river that drains past that point. The watershed is a hydrologic unit that often is used as a physical – biological unit and a social – economic political unit for the planning and management of natural resources. Remote Sensing (RS) and Geographic Information System (GIS) techniques can be used effectively to generate the land use/land cover for evaluating the changes in an area. Conventional methods of runoff measurements are not easy for inaccessible terrain of Tamilnadu. Remote sensing technology can augment the conventional method to a great extent in rainfall-runoff studies. In this study, SCS Curve Number technique modified for Indian condition has been used for generation of CN for an ungauged watershed. A sub watershed of Manimuktha watershed is considered as study area. The daily rainfall data of Virudhachalam rain gauge station is collected and used to predict the daily runoff from the watershed using GIS based Soil Conservation Service -Curve Number (SCS – CN) method (USDA, 1972). Monthly and annual runoff values are obtained from the daily runoff values of the watershed. Base map, Soil map and Land use map of the study area are prepared by using Remote Sensing data and Survey of India (SOI) toposheets. PC Arc/Info GIS software is used for analysis.

ABSTRACT

The use of Geographic information system to locate groundwater possible zone in Valapadi taluk of Salem was carried out using remote sensing and geophysical studies. The remote sensing methods involved in the visual interpretation of the satellite images for hydrogeomorphological and hydro structures favourable for groundwater. The geophysical method involved vertical electrical soundings to predict the sub-surface variation and to locate the water domain. Three geoelectric layers were delineated from the interpretation of vertical electrical sounding data and the map of the above results predict the depth extent of groundwater zone. The spatial distribution of the above results was identified through GIS.

ABSTRACT

The present paper highlights the implication of geochemical strategic tools to choose suitable site selection on the coastal region. Geochemical tools and geomorphological survey have been also deployed to identify the suitable site. The geomorphology of the site A reveals enough fresh water accumulation was found and the two elevated crest and the adjacent trough (low land) with surrounding areas further support the fact. The water quality of this site exposes very good quality (< 200ppm TDS) and the dissolved major anions (HCO3, SO4, Cl) and cations (Ca, Mg, Na, K) concentration are well within drinking water standards. The soil samples are of medium to coarse sand nature showing high porosity (40 to 50%) with mica flakes acting as less permeable in nature. The water quality shows very good in nature and similar to Site A. The soil characters additionally proved good in porosity and permeability (SAR 1.5 to 2.1).

ABSTRACT

The coastal zone is environmentally sensitive and economically valuable, which has great attention from researchers especially from geoscientists. Coastal zone has great threat from pollution and natural calamities like cyclones, flood and tsunami. Natural calamity is a frequent phenomenon over coast. Therefore, it is very essential to monitor the changes over coastal ecosystem and geomorphic features like beach, shoreline and sand dunes. In this case, one of the basic requirements in managing and monitoring these features is the topographic data. The recently emerged technique of Airborne Altimetric LiDAR provides accurate topographic data. It is in preparatory stage in India. By this technique, we can collect the data at high speed when disaster happens. This paper attempts to provide a general overview of the role of LiDAR in coastal management.

ABSTRACT

In order to assess the baseline environmental status in the PTK mines the comprehensive primary data collection / survey programme was undertaken during the period i.e. from April 2003 to June 2003. The environmental monitoring for ambient air quality, water quality, soil quality, noise levels, dust fall, traffic density, meteorology of the study area, etc was carried out. Detailed satellite image interpretation was carried out and thematic maps of the study area were prepared by visual interpretation using tone, texture variations from IRS –IC LISS-III – False Color Composite geo coded images. Digital image processing techniques (supervised classification) were used to classify land use, geology, geomorphology, and drainage pattern/ watersheds and soil cover of the study area. Detailed flora and fauna study was carried out in the study area comprising of core and buffer zones for identification of existing species. The description of baseline environment in the study area is given below.

INTRODUCTION

Remote Sensing is an indigenous tool for the Environmental Impact Assessment study. It plays vital role in preparing various thematic maps for understanding the changes that have taken place in an area before and after the establishment activities. In this study we have utilized the capability of the remote sensing techniques in understanding the mining environment. Our study area is in and around the Dalmiapuram Cement Industry in the central part of Tamil Nadu state and it covers part of Trichy and Perambalur districts. It falls between 11₀ 02’ 42’’and 1₀ 03’ 08’’E and 79₀ 09’ 39’’and 79₀ 10’ 30’’N.Dalmiapuram Cement Industry is located in the Kovandakurichi village of Pullambadi block, Trichy district. The mines for cement manufacturing are Perianagalur (PNR), Periathirukonam (PTK), Kallakudi (KLK), Kovandakurichi (KVK) and A&K Mines.

The litho units are Limestone beds containing various proportions of bioclastic and siliciclastic materials. They show wackstone to rudstone fabric and have clasts of re-deposited bound stones. Deposition in a periodically restricted shallow marine setting was indicated by lithological and faunal information. Lower contact is an unconformity surface associated with marine flooding and the upper contact is non-depositional and erosional with overlying biostormal member.

ABSTRACT

The present work relates to geological and commercial aspects of pyroxene syenite (Green Onyx) occuring in and around Sivamalai of Periyar District in Tamil Nadu. The alkaline complex of Sivamalai comprises syenites-, nepheline syenite and their variants. Pyroxene syenite is possibly the oldest within the syenite complex occurring as minor massifs, elongated linear bodies, -arcuate islands and enclaves within feldspar syenite are observed in the hillocks North East of Sivamalai, namely Chennimalai and its southern extensions. On the commercial point of view, the pyroxene syenite in the study area occupies nearly 30 square -kilometres area and can be categorised as Kalleri Block, Neykkarampalayam Block and Sivamalai Block. The observed petrographic and petrochemical characters of the alkaline rocks of the study area favours magmatic origin for these rocks. A detailed geological study and random market survey of individual syenite bodies proved the true worthiness of the material Green-Onyx as a dimensional stone with substantial resources and market potential.

ABSTRACT

Granite in the present day context is popularly known as the principal raw material in construction industry and also known for its value addition product as Dimension Stone in the global market. India is in pride possession of much sought granite varieties of the world. No doubt the demand for such granite varieties is quite high both for local and export markets but in reality the failure rate of granite quarries is also high, The technical reasons attributed for such failures being lack of application of proper scientific skill both in selection and mining ofgranite deposits. The past experience in the fieldof granite exploitation has thought us a lesson for application of geological knowledge in selection of right deposits and in adopting the right techniques. The selection criteria for construction purpose and for export market though looks simple, is more complicated in the case of dimension stone granite deposits, the reasons being the requirement of thorough knowledge in petrography,structure,geotechnical characters of the deposit. Considering the importance of the scientific knowledge, the present paper focuses on the various parameters for valuation of granite deposits. In other words, it emphasizes on arriving at a logical conclusion by applying the scientific knowledge in successful exploitation of the much valued granite deposits.

1.1 Introduction and Background

In present scenario, the word “extrusion” refers to a process by which dry or semi-moist ingredients with varying in-barrel moisture are forced through varying barrel temperature, screw speed and screw configuration through a die opening of the desired cross section. In other words, extrusion is predominantly a thermo-mechanical processing operation that combines several unit operations, including mixing, coating, kneading, venting, shearing, heating, forming, partial drying or puffing, depending on the material and equipment used.

The origins of extrusion are in the metallurgical industry, where in 1797 Joseph Bramah patented the first extrusion process, wherein a piston driven device was used for making seamless lead pipes. The present understanding of extrusion technology and the developments or improvements in machine design are largely due to research carried out by the plastics industry. In food industry, this technology is in use since 1930 and its popularity is increasing continuously due to its efficiency, continuity and sustainability. In beginning, sausage extruders were developed in the nineteenth century as simple forming machines. One of the original developments which laid the foundation of the food extrusion was the use of pasta press termed as “cold extruder” in mid 1930s. Furthermore, in the late 1930s, General Mills, Incorporation., Minneapolis, MN, USA, first used a single screw extruder in the manufacture of ready-to-eat (RTE) cereals. Later in 1970s, twin screw extruders were used for the manufacture of moist pet-foods. Twin screw extruders were also adapted from polymer industry, as rising food quality and limitations of single screw extruders were demanding a more versatile process for the newer and higher quality products. After 1970s, the extrusion processing with simultaneous use of heat was popularized as a versatile and highly energy efficient with negligible wastage process. In all these years, number of changes has been noted in the extruder design such as changes in screw design, barrel design and also material used for the manufacture of these materials. Barrel liners availability along with already available segmented screws could further add more economics to the process and increased equipment lifetime. For better wearing characteristics, a number of screw elements of different materials are being used in addition to standard nitrided steel for customized processing needs, such as corrosion and wear resistant surface coated steels, stainless steel, satellite welded and bimetallic HIP (Hot Isostatic Press). JBL Feedscrews Limited, a UK based company recently introduced tungsten carbide coated screw in conjunction with a compatible bimetallic barrel. Likewise, a number of options for barrel metallurgy are available to withstand the higher internal pressure and temperature. Barrels lined with hard cobalt based alloy, typically Xaloy, to give abrasion and chemical resistance are also in use, although, the most common material is carbon steel with a nitride interior. Similarly, steam heated or jacketed barrels were used earlier for cooking purpose which gradually replaced by the electric induction heating elements. These HTST cooking extruders are versatile, highly productive and energy efficient processing machines. They can use a wide variety of raw materials and formulations to produce products with increased shelf-life and convenience.

2.1 Introduction

Food is one of the complex systems involving many constituents such as carbohydrates, lipids, proteins, vitamins, minerals and other phytochemicals. These all constituents are not present in the same relative proportion in every type of food and thus the foods are categorized and valued according to the presence of these constituents as protein rich foods, fat rich foods, etc. The specific type of food is in abundance with only one or at most two of these constituents and rest of the bulk is not valuable, commercially. So, if these active constituents which are present in the tissue surrounding inactive matrix, are separated, it is of great benefit with respect to increased purity, nutritive value, functional properties, reduction in volume, easy handling and transportation. On contrary some valuable food items contain undesirable constituents generally referred as anti-nutritional factors. Removal of these anti-nutritional factors enhances the food value and commercial utilization. Hence, the separation of phytochemicals and removal of anti-nutrients from the food matrices can be easily carried out by using a unit operation called as extraction.

Extraction involves the separation or isolation of active/desirable components of complex system viz., plant and animal tissues from the rest of inactive/undesirable components by using suitable means such as solvent or mechanical structure. The basic principle involved in the extraction process is partitioning of different components in accordance with the extracting agent. For example, in mechanical extraction, the partitioning is due to pressure and screen/apperature size where as in case of solvent extraction, the portioning of components from mixture takes place due to particular solubilizing power of solvent used.

3.1 Introduction

Energy comes in many forms like chemical, radiant, mechanical, electrical, nuclear etc and can transform from one type to another. Energy can also be transferred or moved from one object to another. Electromagnetic (EM) radiation is a form of energy that can take many forms, such as radio waves, microwaves, X-rays and gamma rays even sunlight is also a form of EM energy. Visible light is a small portion of the EM spectrum, which contains a broad range of electromagnetic wavelengths.

Electromagnetic waves, a self –propagating transverse radiation, are created when an atomic particle, such as an electron, is accelerated by an electric field, causing it to move. The movement produces oscillating electric and magnetic fields. The electric and the magnetic components of the wave are perpendicular to each other and also perpendicular to the direction in which wave is travelling in a bundle of light energy called a photon. Photons travel in harmonic waves at the fastest speed possible in the universe: 186,282 miles per second (299,792,458 meters per second) in a vacuum, also known as the speed of light. There are three important characteristics of the electromagnetic radiation, its frequency, amplitude and speed (Figure 3.1).

4.1 Introduction

The purpose of processing the food is to make it safe and healthy for human consumption. The term food processing refers technologically anything, which transforms raw ingredients into consumer ready products, with the aim of stabilizing food products by preventing or reducing deteriorative changes in quality. The objective of food manufacturers is to develop, modify and employ those processing technologies that retain or create desirable sensory qualities in food and eliminate or reduce undesirable changes due to processing.

The purpose of food processing is to increase the shelf life of food before spoiling (preservation); to remove, destroy or inhibit pathogens and toxins (food safety); to change flavor, texture, aroma, color or form (variety); to reduce preparation times and make food more portable (convenience); to restore and/or raise nutrient levels in food (nutrition).The various food processing methods used extensively in food industry include physical (high temperature, freezing, chilling, dehydration, packaging), chemical (control of storage gases, reduction of water activity, pH, addition of chemical additives or spices) preservation methods.

Traditionally, food preservation has been associated with thermal treatments alone or in combination with biochemical or chemical methods. For example, the thermal processing of milk is done various thermal treatments viz. at 63^oC for 30 min for low temperature long time (LTLT), 72^oC for 15 seconds for high temperature short time (HTST) pasteurisations and up to 140^oC for a few seconds for ultra high temperature (UHT) treatment. However, such thermal treatments effectively reduce level of microorganisms but in long-term preservation, it may lead to losses of desired organoleptic attributes and destruction of temperature liable nutrients and vitamins. The limitations involved with thermal processing has been overcome by employing chemical preservation, cool chain management and process hygiene in the formulation and production of food products.

5.1 Introduction

Food is the basic requirement of every living being and it provides physical, mental as well as emotional satisfaction. Globally, there are many food enterprises which provide this basic necessity across the nations irrespective of nature of origin and climatic condition. Food companies are required to provide products at certain quality parameters so as to maintain the uniformity in the food system. Hence, food quality can be defined as a total of traits and criteria which characterize food as regard to its nutritional value, sensory value, convenience as well as the safety for a consumer’s health. Food quality is the quality characteristics of food that is acceptable to consumers. This includes external factors as appearance (size, shape, colour, gloss and consistency), texture, and flavor; factors such as grade standards and internal (chemical, physical, microbial). Due to the various food risks, all over the world the quality regulation authorities have intensified the efforts to improve food quality. Some of the quality related systems are obligatory by law while other is voluntary which are to be implemented by the various food chain members.

Many companies are forced to improve safety and quality of their products by implementing the quality and safety assurance and management system because of growing consumers’ expectations and concerns as regards food quality and safety.

In order to attain maximum profit and decrease the flaws, a new system was developed and followed by various companies all over the world. This new system is known as Six Sigma. The application of this system has the capability to reduce the losses considerably by reviewing the process parameters and increasing the profit exponentially. It constitutes a systematic approach to assure that food products have particular traits at any stage of production and distribution.

6.1 Introduction

Consumer demand, regulatory guidelines and economic power of the consumer as well as ascertained profitability stimulated the need of novel food processing techniques. The concept of “fresh”, “natural”, or “organic” food also led to the development of environmentally sound and resource efficient food processing technologies. Thermal processes have been used for food preservation since a long time. These are not very energy efficient and can change the phase of food from fresh to cooked as well as it can alter the nutritional and sensory qualities. Thus, the quest for energy conservation by the manufacturers to reduce carbon footprint of the processes involved in food processing and preservation as well as to fulfill consumers’ requirement for fresh-like quality food have given rise to the development of innovative non-thermal food processing technologies i.e. ionizing radiation, high-intensity light pulses, high isobaric pressure, electric or oscillating magnetic fields, as well as pulsed electric fields (PEF).

Application of electric energy in food processing started in the early 1900s. In the beginning, electrical pasteurization inactivated microorganisms by increasing the temperature of samples by means of an electrical resistance (ohmic heating). Milk was the first electrically pasteurized product. In the late 1940s, electric fields were used to increase the permeability of fruits to facilitate the subsequent extraction of juices. The PEF technology as a non-thermal process is very effective for inactivation of microorganisms, increasing the pressing efficiency, enhancing the juice extraction, and for intensification of the food dehydration and drying process. The main effect of PEF technology is based on the phenomena that biological membranes are punctured under the influence of external electrical impulses. This process is often referred as non-thermal, since the structural damage to membranes is implemented at very low temperature compared to the conventional heating process. The PEF process is considered to be energy efficient because the electric energy is released in short pulses, thus total energy requirement is much lower than other continuous preservation technologies. The microbial inactivation can be achieved at ambient or moderately elevated temperatures by the application of short-bursts of high intensity electric fields to liquid foods flowing between two electrodes or to semi-solid/ solid food between some specialized electrode and treatment systems. Due to chemical/physical properties and presence of electrical charge, the liquid foods (e.g. milk or fruit juices) had different conductivity, which results in variable flux of electrical current through the food systems.

7.1 Introduction

Food processing has become one of the most competitive sectors in recent years. With increasing consumers’ demands, food industry needs to keep updating technology. These efforts are focussed at improving the organoleptic quality and nutrition of food and improve its keeping quality. This drives the industry to look for newer technologies which include new products as well as new processes. Some of the new processing technologies include non-thermal processes such as high pressure processing, pulsed electric fields and ultrasound processing. Advanced thermal processing techniques such as ohmic heating, inductive heating, extrusion and infrared heating have also been developed. Innovative methods for improving food quality through irradiation, removal of heat and moisture from food are now available. Newer packaging techniques now help to improve shelf-life and attractiveness of the food products and cater to the biodegradability of the packaging material. Hence, there is abundance of new products that have now become part of our daily life.

Food nanotechnology has its long history when the first step of revolution in food processing and improvement in quality of foods was introduced by Pasteur to kill the spoilage bacteria (1000 nm). Later, Watson and Crick’s model of DNA structure, which is about 2.5nm, opened the gateway of applications in biotechnology. Nanotechnology is defined as the design, production, and application of structures, devices, and systems through control of the size and shape of the material at the nanometer (10^-9 of a meter) scale. Nanotechnology is one such technology that has the potential to revolutionize the food industry. Taniguchi first used nanotechnology in 1974 to describe production technology at ultrafine dimensions. The word “nano” means “dwarf” in Greek and one nanometer is equivalent to 10^-9 m. Objects of this scale are not visible through the human eye or the ordinary optical microscope. A nanometer (nm) sized particle measures one billionth of a meter. A human hair measures 80,000 nm while a DNA strand is 2.5 nm wide whereas a protein chain is 5nm in diameter. Nanotechnology can be applied to develop nanoscale materials, controlled delivery systems, contaminant detection and to create nanodevices for molecular and cellular biology. Nanotechnology may be defined as the understanding and management of matter at dimensions of roughly 1-100 nanometers. Unique behavior of matter at the nanoscale enables novel applications. Nanoscale science, engineering, and technology can be used for imaging, measuring, modeling, and manipulating matter at this length scale. Range of sizes of nanomaterials in the food sector and their relative position on nanoscale/microscopic scale are listed below.

8.1 Introduction

Electron Microscopes were developed due to the limitations of Light Microscopes which are limited by the physics of light to 500x or 1000x magnification and a resolution of 0.2 micrometers. In the early 1930’s this theoretical limit had been reached and there was a scientific desire to see the fine details of the interior structures of organic cells (nucleus, mitochondria etc.). This required 10,000x plus magnification which was just not possible using Light Microscopes. The Transmission Electron Microscope (TEM) was the first type of Electron Microscope to be developed and is patterned exactly on the Light Transmission Microscope except that a focused beam of electrons is used instead of light to see through the specimen. It was developed by Max Knoll and Ernst Ruska in Germany in 1931. The first Scanning Electron Microscope (SEM) debuted in 1942 with the first commercial instruments around 1965. Its late development was due to the electronics involved in scanning the beam of electrons across the sample. Electron microscope has been a valuable tool in the development of scientific theory and it contributed greatly to biology, medicine and material sciences. This wide spread use of electron microscopes is based on the fact that they permit the observation and characterization of materials on a nanometer (nm) to micrometer (µm) scale. Electron Microscopes are scientific instruments that use a beam of highly energetic electrons to examine objects on a very fine scale. This examination can yield information about the topography (surface features of an object), morphology (shape and size of the particles making up the object), composition (the elements and compounds that the object is composed of and the relative amounts of them) and crystallographic information (how the atoms are arranged in the object). A scanning electron microscope (SEM) is a type of electron microscope that produces images of a sample by scanning it with a focused beam of electrons. The electrons interact with atoms in the sample, producing various signals that can be detected and that contain information about the sample surface topography and composition. SEM can achieve resolution better than 1 nanometer. The combination of higher magnification, larger depth of focus, greater resolution, and ease of sample observation makes the SEM one of the most heavily used instruments in research areas today.

9.1 Introduction

Food quality and safety are central issues in food economics today. A number of developed countries (EU, UK, US) has imposed a number of new regulations to track food products across the supply chain which is forcing the companies to invest in new automated approaches for their implementations. These solutions facilitate better process efficiency with more productivity, quality control in production lines, lower manufacturing costs with higher profit margins, and also help to achieve improved presentation as customers request. The high labour costs in developed countries make cost-cutting inevitable to remain competitive production. The growth in products packaged for the market, the increasingly strict hygiene regulations, the need to reduce risks at work, cut costs, and control product quality are all calling for the development of technologies that enable robots to be used for these tasks. In fact, robotics has a great opportunity in this industry. But the variation in physical properties of various food products and the necessity to avoid damaging them, make it necessary to seek flexible handling solutions for a wide range of products.

The robotics industry is looking into a bright future. As per the report given by the Statistical Department of International Federation of Robotics (IFR), it was projected that between 2014 and 2016 worldwide robot sales will increase by about 6% on average per year. Ten years ago, global sales figures were hovering around 80,000. So, three key factors for the boom - factory modernization, increases in production capacity and rising demand from a number of emerging markets.

10.1 Introduction

Food safety and quality are the two important factor which results in consumer food choices. Nowadays consumers are demanding food which is safe and of high quality in terms of nutrition due to a healthier life style. Food safety and quality are the terms used interchangeably. Food safety refers to all those hazards, that make food injurious to the health of the consumer and it is not negotiable. Food quality includes attributes that influences the product's value to the consumer. This includes both negative and positive attributes; negative attributes includes spoilage, contamination, discoloration, off-odours and positive attributes include colour, flavour, texture and processing method of the food. This distinction between safety and quality has implications for public policy and influences the nature of the food control system. Food control is defined as a mandatory regulatory activity which provides consumer protection and ensures food is safe, wholesome and fit for human consumption during production, handling, storage, processing, and distribution.

Despite the huge efforts made by the food safety authorities and industries, food safety still remains a critical issue. In food industries, producers have to satisfy both safety and quality criteria for their products to the consumer. Food processors have multiple options in terms of different quality and management systems, they have to choose the most appropriate one for its specific activity and should establish, document and implement effective systems in the processing area for managing quality and safety of the product. Over the past few decades, food-borne illnesses have raised great concern about the safety of food. Considerable steps are taken by the food processor for understanding and managing the risks of airborne diseases. Among various systems, Hazard Analysis and Critical Control Point (HACCP) is effective tool which focuses mainly on controlling hazards to ensure the production of safe and wholesome food. For maintaining the safety and increasing the shelf life of food, traditionally it has been preserved by thermal processing, freezing, salting and drying. But nowadays consumers are demanding convenient, innovative, fresh foods, including new "minimally processed" products. To meet consumers' expectations in the 21^st century, the food industries are implementing novel technologies whose purpose will be two fold: 1) to provide the new quality attributes demanded by consumers; and 2) to ensure the all important and often expected assurance of food safety. The novel technologies will include various minimally processed technologies like high pressure processing (HPP), pulsed electric field (PEF), ohmic heating, dielectric heating, microwave heating, ultrasound, modified atmosphere packaging (MAP) and cleanroom technology. Among these cleanroom technology have attracted great attention for maintaining the safety and quality of the food products as because it doesn't have any effect on the nutritional quality of the food being processed, it maintains the hygienic condition in the processing area, remove contaminants from the processing area and clean air in the processing area which in turn results in safe food product. The main objective of cleanroom technology is to eliminate airborne contaminants from the humans and/or from the environment. An air curtains and a positive air pressure is maintained in the processing unit using filtered air. Production personnel will use the special clothing which is preferred for cleanroom to reduce the contamination from both air- and human-borne microorganisms. In this chapter we will discuss about cleanroom technology, its historical background, its classification, layout of cleanroom, air handling, personnel and its clothing, regulations in cleanroom, and its application in food industries.

11.1 Introduction

Phytosterols or plant sterols are bioactive plant constituents having similar chemical structure and biological functions as cholesterol (cholest-5-en-3b-ol), but differ in their side chain configuration. They are non-nutritive compounds with chemical structure differing from that of cholesterol only by minor modifications like in the structure of their side chain by a methyl or ethyl group at C-24. Sitosterol and campesterol have an ethyl and a methyl group at C-24, respectively (Fig. 11.1). Phytosterols present a tetracyclic ring and side chains linked to C-17 that differ according to sterol compound same as cholesterol, to which they resemble structurally as well as biosynthetically. Saturated form of sterols referred to as stands, occurring in small amounts, mainly in cereals are represented by the absence of the double bond at the D5 position. Phytosterols represent a part of the broad group of isoprenoides and are 28- and 29-carbon atom steroid alcohols naturally occurring in plants. Phytosterols and phytostanols are triterpene compounds, found ubiquitously in plants which can only be synthesized by plants, whereas humans and animals obtain them from their diet.

12.1 Introduction

Micronization is a size reduction in which particles are reduced down to micrometer resulting in particle-size distribution is less than 10 microns. Acceleration of particles has been involved for particle-to-particle impact or impact against a solid surface. Micron technology is an emerging technology which has a great potential in nutraceuticals and functional foods. By increasing the surface area per unit mass, compared with larger-sized particles of the same chemistry, tiny particles are made more biologically active. A lot of attention has been gained by micronization in food research and development. Functional properties, surface areas and structures gets altered by reduction in particle sizes of different materials (e.g., metal salts, metal oxides, chitosan and organic compounds) by micronization or nanotechnology to micro- or nano-sizes and bring some new applications in the academic world as well as in food industry.

They absorb a large concentration (10-40 wt %) of C0₂ that either swells the polymer or melts it at a temperature below (10 to 50 °C) it’s melting/ glass transition temperature hence, this technique is useful for micronization of especially for polymers. Active substrate(s) in a polymer or other carrier substance can be used with suspensions for micronization process. In manufacturing advanced pharmaceuticals, coating materials, micro sensors, polymers and many other chemicals particle design has been gaining importance. Formulation homogeneity and control particle size can be improved by micronization. Moreover, bioavailability of poorly soluble APIs (active pharmaceutical ingredient) by increasing particle surface area and accelerating dissolution rates can also be improved. Because of the high impact velocities possible as a result of particle acceleration in a fast gas stream, fluid energy mills are used for micronization. Particle velocities in a jet mill are in the range of 300 to 500 meters per second, compared to 50 to 150 meters per second in a mechanical impact mill, in many industrial fields like food technology, pharmaceuticals, catalysts, pigments, and biopolymers, for example, are some categories of products that can be used as micro-sized particles, micronized powders are of great interest. High-temperature reactions that require high energies, on jet milling that is characterized by low efficiencies and mechanical stress, and on liquid solvents precipitation that has a poor control on particle size and can pollute the product comes under the traditional techniques for producing micronic powders. Generally, the control of the powder size and the span of its distribution are still very approximate. In recent years, many supercritical fluids-based techniques have been developed for the production of micronic and nanometric particles. Some particular properties of gases at supercritical conditions such as enhanced solubilization modulation and its power, large diffusivities, organic solvent reduced operation, and the connected possibility of controlling powder size and distribution resulted from this process. Important characteristics of powders like particle size and size distribution have significant effects on dissolution properties, flowability and release kinetics. Therefore, particle engineering is the most important step during processing of powdered foods. Lower micrometer range and sizes are needed for many applications particles with special requirements. Processes like jet milling, pearl milling or high pressure homogenization are used for micronization.

13.1 Introduction

A surfactant or surface-active agents are the compounds that lower the surface tension between the two liquids or between a liquid and a solid. Surfactants may act as detergents, wetting agents, emulsifiers, foaming agents and dispersants. Surfactants are normally organic compounds that are amphiphilic, meaning they contain both hydrophobic groups or hydrophilic groups. Therefore a surfactant contains both a water insoluble component and a water soluble component. Surfactant will diffuse in water and adsorb at interfaces.

The interfacial free energy is the minimum amount of work required to create that interface and the interfacial tension between two phases is determined as the interfacial free energy per unit area. The interfacial (or surface) tension is also a measure of the variance in nature of the two phases meeting at the interface (or surface). The greater the dissimilarity in their natures, the greater the interfacial (or surface) tension between them. A surfactant is therefore a substance that changes the amount of work required to expand those interfaces. Surfactants usually act to reduce interfacial free energy.

Surface active agents in the form of emulsifiers have a long history of use and are widely used in many products being used in everyday life. An extensive basic research is required to understand the reason of instability and methods to prevent the breakdown of emulsions. Emulsifiers can function as dough conditioners by improving tolerance to variations in flour quality, better gas retention resulting in lesser yeast requirements, increased uniformity in cell size, a finer grain, more resilient texture and improved slicing. Also, the characteristics of freshly baked bread like soft crumb can be retained longer, if the appropriate emulsifiers are added. Commonly used surface active agents in bread production are propylene glycol mono- and diesters, polyoxyethylene sorbitan monostearate, ethoxylated mono- and diglycerides, succinylated monoglycerides and Diacetyl tartaric acid, esters of monoglycerides. Cookie characteristics like top grain, volume and spread ratio can also be improved. Here surfactants used are sodium stearoyl fumarate, sucrose fatty acid esters, sodium stearoyl lactylate, sorbitan fatty acid esters, polysorbates and ethoxylated monoglycerides. In dairy products like Ice cream surface active agents play some important functions like to improve fat dispersion and control fat agglomeration, facilitation of fat– protein interactions, facilitate air incorporation, give smoother texture due to smaller ice crystals and air cells, increase resistance to shrinkage, improve melt-down and reduce whipping time. In candy products, the elimination of “bloom,’’ i.e., the transition of fat crystals is a key reason for the addition of surface active agents. In mixtures of triglycerides, surfactants like sorbitan esters (Spans) and ethoxylated sorbitan esters (Tweens) can control product viscosity in chocolates and in cream fillings and modify the crystal structure. Surface active agents have been utilized in the production of meat analog products also. In margarine, Emulsifiers fulfil several functions like modification of crystal structure in the vegetable fat, assistance in emulsion formation and antispattering. Here, a mixture of citric acid monoglycerides and monoglycerides or lecithin can be used. The properties and mode of action of these chemical surfactants is discussed in the following sections.

14.1 Introduction

Proteins are the substances formed from nitrogen containing amino acids and are principle structural components of body tissues and muscle. In addition, they are used to produce various hormones, enzymes and hemoglobin in human body. Due to the shift from agricultural to electronics and other fast paying industrial development, most of the countries around the world, ceased to be self-sufficient in their food production in particular protein, which is necessary to satisfy their optimum food demands. The biotechnology development and its usage to agriculture have brought hope to them. The need for food by modernization of agriculture has gained much attention throughout the world. However, the necessity for exploring unconventional and non-agricultural means of food production, especially of proteins rich food, cannot be over-emphasized due to the tremendous growth of human populations in several regions of the world. In addition to this, the importance of protein in food nutrient cannot be put aside because its shortage causes various malnutrition problems and the most lethal malnutrition problem is Protein-Energy-Malnutrition (PEM). The United Nations Food and Agriculture Organization estimates that nearly 870 million people of the 7.1 billion people in the world, or one in eight, were suffering from chronic undernourishment in 2010-2012. There are 925 million people undernourished in developed countries (FAO October, 2010). This situation has created a demand for the formulation of innovative and alternative proteinaceous food sources having high nutritional value. These sources have to be non-competitive with food for human consumption, economically feasible and locally available. This demands a search for new protein sources, with high nutritional value, economically feasible and locally available. Use of microbes as a food source is one of the biotechnological innovations that will certainly increase the availability of affordable protein in the world to solve the global food and feed problems.

In recent decades there has been an increased interest in the industrial production of microbiological protein for use in both human and animal nutrition. The main reason behind it is that there has been the shortage of low cost protein sources in view of the increasing human population and living standards, resulting in famine in some parts of the world and increased demand for animal protein in others.

15.1 Introduction

Color of food is the most sensitive part of any commodity as it is the one of the organoleptic characteristic to be noticed and one of the main ways of visually assessing a food before it is consumed. The people associate certain colors with certain flavors and the color of food can influence the perceived flavor in anything from confectionary to beverages. For this reason, food manufacturers add dyes to their products. Sometimes the aim is to simulate a color that is perceived by the consumer as natural, such as adding red coloring to glace cherries, but sometimes it is for effect, like the green ketchup that was launched by Heinz in 2000. If the flavor of a food product is inconsistent with the color, the flavor can often be perceived incorrectly, for example an orange flavored drink colored green could be perceived to taste of lime. In addition, the color of a food substance is important indicator of its freshness. While all of us are aware that food with bright or unnatural colors likely contains food coloring but only few people know that natural foods such as oranges and salmon are sometimes also dyed to mask natural variations in color. The color variation in foods throughout the seasons and the effects of processing and storage often make color addition commercially advantageous to maintain the color expected or preferred by the consumer. Some of the primary reasons include:

16.1 Introduction

Food safety is most important issue in today's global environment. To safeguard food supply is a very difficult and challenging responsibility, as a consequence of which the world's largest food companies, retailers, and manufacturers have placed very high food safety standards. Although the safety of food has improved exponentially but progress is uneven and food borne outbreaks due to microbial contamination, pesticides, antibiotics chemicals and toxins are common in many countries. International trade statistics (2007) by World Trade Organization (WTO) reported that Europe has accounted for 46% of world exports of agricultural products, where food represents 80% of agricultural exports. The trading of contaminated food among countries increases the risk for outbreaks and consequently, health risks due to microbial pathogens in food are of major concern to all governments.

Biosensors are an important option in the agricultural and food sectors to control production processes and ensure food quality and safety by dependable, fast and cost effective methods. Biosensors have plenty of advantages over conventional analytical tools since they offer advantages in size, cost, inherent specificity, selectivity, rapid response, accuracy and sensitivity. Food microbiologists are always in search of rapid and reliable automated systems for the detection of biological activity. Biosensors provide sensitive, miniaturized systems that can be used to detect unwanted microbial activity or the presence of a biologically active compound, such as glucose or a pesticide. Immunodiagnostics and enzyme biosensors are two of the leading technologies that have had the greatest impact on the food industry. The use of these two systems has reduced the time for detection of pathogens such as Salmonella to 24 hour and has provided detection of biological compounds such as cholesterol or chymotrypsin. The another useful application for biosensors, is detection of genetically modified organisms (GMO), since several countries have laws regulating the commercialization of GMO products and their derivatives. Biosensors are also useful in the implementation of hazard analysis and critical control points (HACCP) plans by verifying process developments and correcting errors in due time. There is joint application of Biosensor technologies and nanotechnologies in many food and agricultural applications such as the development of nano-scale tools for biosafety, nanoscale compounds for food packaging, and nano-sensors for pathogen detection in animals and plants. These are helpful tools in the detection and control of potential food contaminants by the agricultural and food industries.

Due to inadequate intakes of vitamins and minerals, half of the world's population suffers from micronutrient malnutrition. An adequate amount of wholesome as well as diverse foods are required for the proper growth and development. In addition to calories requirements, these foods should provide various nutrients. In India, ~70% of children do not get the required calories either due to lack of enough food or diverse food. This indicates that these children are also incapable of fulfilling their protein, minerals and vitamins requirements. Diets that lack diversity can be deficient in certain nutrients. Due to the micronutrient composition of the soil of a region, or because of the intrinsic insufficiency of the normal diet the staple foods of some region can lack particular nutrients. The individual plant foods are often deficient in certain nutrient components due to the varying level and composition of food nutrients in different food crops. Some crops are rich in one component but low in other. For example; legumes are usually high in protein, but deficient in essential amino acids like methionine whereas, wheat and rice are rich in carbohydrates but contain little essential amino acid such as lysine, iron, and lack provitamin A. Relying on a single food crop as major staple source of nutrients thus will not attain a nutritionally complete diet and result in malnutrition and deficiency diseases, which often occur in populations of developing countries, mainly due to poverty. Globally, over one billion people are undernourished and food security is a major issue with the world's population forecast reaching to nine billion by 2050.

18.1 Introduction

The Packaging Institute International describes packaging as the enclosure of items, packages or products in a wrapped pouch, box, bag, cup, can, tray, tube, bottle or other container for protection, preservation, containment, communication, performance and utility. To an engineer or a scientist, it is technical matter as it is a system designed for efficient delivery of safe food products with high quality, via each and every stage of distribution chain, from production of raw material to food manufacture, packaging, retail, wholesale, consumer, disposal and finally recycling or of resource resurgence. The extent of food packaging is literally broad as it encompasses technological activities such as graphic and machinery design, package manufacture and development, shelf life testing, distribution and marketing. Food packaging science is a discipline which applies principles from four major areas of science (materials science, food science, information science and socioeconomics) to understand the properties of packaging materials, packaging requirements of foods and the packaging system. Both material science and food science have been two major contributors for food packaging development. Material science is important to understand the mechanical strength, barrier properties, appearance and physical and chemical properties of paper, glass, metal, polymer and composite. Food science is important to understand the deterioration kinetics of foods (such as microbial growth, lipid oxidation, moisture loss or gain) governs the food shelf life. Food packaging technology is a science based solutions to address specific food packaging needs; examples are tamper evident packaging, microwavable packaging, modified atmospheric packaging, and controlled atmospheric packaging which are aimed at enhancing safety, quality and convenience for the consumer.

19.1 Introduction

Food safety is one of the important factor for food industry, regulatory agencies and consumers. Nowadays consumers are demanding food which is safe and of high quality in terms of nutrition due to a healthier life style. Food safety refers to all those hazards, that make food injurious to the health of the consumer and it is not negotiable. Food may be contaminated physically, chemically or microbiologically, mainly microbial contamination is of high concern in the food industries. Various pathogenic and spoilage causing microorganisms, viruses, insects can deteriorate the food products and cause food borne illnesses. Therefore, there is a need to eliminate these undesirable microorganisms from the food industries to ensure food safety to the consumer. Various methods are available to eliminate these undesirable microorganisms such as thermal technologies like pasteurization, dehydration, retort processing, freezing etc. and non thermal technologies like microwave heating, Pulsed Electric Field (PEF), High Pressure Processing (HPP), Pulsed Light Technology, Ohmic Heating, Ultra sonics, Pulsed X-Rays. But these technologies have certain disadvantages like thermal technologies lowers the nutritional value and leads to unwanted changes in the foods' sensory attributes of the food products whereas non thermal technologies retain better nutritional and sensory quality of food than thermal technologies but they are cost effective, required specialised equipments and trained personnel. Cold plasma technology (CPT) is a non-thermal green technology used now-a-days for variety of application in various industries especially in food industry. It is proposed to be an alternative method for eliminating microorganism from the fresh produce. This technology does not require extreme process conditions and can be used as a good alternative source for food preservation without affecting its nutritional and sensory attributes. Plasma is an ionized gas, consisting of active species like positively and negatively charged ions, electrons, free radicals, and gas atoms, metastable and quanta of electromagnetic radiation (photons). When the energy source is turned off, active species used to disappear immediately, therefore cold plasma technology is environmental friendly and fulfilling all ecological standards. Based on the properties of plasma, it can be applied in various fields like electronics, life sciences, textile, packaging and food industries. In food industries, it is showing promising application by retaining the nutritional, functional, and sensory characteristics thus ensuring the fresh appearance of the food product and satisfying the consumer need.

The paper deals with the historical perspective of the tsunamis, much widely discussed Kumari Kandam and Lemuria continent and the palaeo-time series changes on the past continents and oceans, disastrous tsunamis since 16^th century and archeological evidences indicating shore line changes along Tamil Nadu coast.

Keywords: Ancient tsunamis in history, Kumari Kandam and Lemuria, Past shore line changes.

INTRODUCTION

A tsunami is a natural phenomenon consisting of a series of waves generated when water in a lake or the sea is rapidly displaced on a massive scale. Earthquakes, landslides, volcanic eruptions and large meteorite impacts all have the potential to generate a tsunami. The effects of a tsunami can range from unnoticeable phenomenon to large scale devastation.

The term “tsunami” is derived from the Japanese language meaning harbour (“tsu”) and wave (“nami”). The term was coined by fishermen who returned to port to find the area surrounding the harbour devastated, although they had not been aware of any wave on the high seas. A tsunami is not a sub-surface event in the deep ocean; it simply has a much smaller amplitude (wave heights) offshore, and a very long wavelength (often hundreds of kilometers long), which is why they generally pass unnoticed at sea, forming only a passing “hump” in the ocean.

Tsunamis were historically referred to as tidal waves because when they approach land they take on the characteristics of a violent onrushing tide rather than the sort of cresting waves that are formed by wind action upon the ocean (with which people are more familiar). However, since they are not actually related to tides the term is considered misleading and its usage is discouraged by oceanographers.

Abstract

There are two distinct types of oscillations in global oceans, separated in their frequencies by the period of the pendulum day. One species is the gravity waves and the other is the rotational waves, associated with earth’s rotation. Both these species can be found in tidal records around islands as well as near coastlines. These two types of modes are usually found in the tsunami records on tide gauges. The tide gauge records as well as visual descriptions of the water levels during and after the occurrence of a tsunami clearly show the presence of these oscillations. During the tsunami of 26th December 2004 in the Indian Ocean, media reports suggested high water levels persisted around the Andaman and Nicobar Islands for several days. These persistent high water levels can be explained by invoking the existence of trapped and partially leaky modes on the shelves surrounding these islands.

Keywords: Oscillations in global waves, Tsunami (2004), Andaman and Nicobar islands.

Abstract

An unprecedented tsunami hit the Andaman and Nicobar Islands and the coasts of Andhra Pradesh, Tamil Nadu, Pondicherry and Kerala on the 26^th of December 2004. The loss of life and property, though wide spread in all these areas, was very severe in thickly populated low lying coasts, such as Nagapattinam in Tamil Nadu. Survey of India, in association with the Department of Science and Technology, Govt. of India, New Delhi has taken-up the task of carrying out post-tsunami Mapping of the entire east coast of Tamil Nadu using Digital aerial stereo images acquired immediately after the tsunami. The project aims to generate ortho-rectified photographs on 1: 8000 scale, which are to be used for preparing damage assessment maps of the affected coastal areas. This paper discusses various issues related to Control Surveying, Digital Photogrammetry and Large Scale feature extraction that are involved in the mapping process in general and its credibility for tsunami damage assessment in particular.

Keywords: Tsunami, Digital Photogrammetry, Tsunami damage assessment in India.

Abstract

The major subduction of the Indian plate and the related high magnitude earthquake (>9M) occurred in Sumatra region, triggered a major tsunami on 26, Dec 2004 which caused massive disasters in many coastal regions of South Asian countries including India, killing tens of thousands of life and causing property loss of several million rupees. Duly realizing the credentials of Geospatial / Geomatics technology and the expertise of NRDMS, an all India coordinated programme was conceived by NRDMS on tsunami disaster assessment and got it executed through six specialized institutions working on geomatics technology in the country. In the programme, the tsunami disaster in terms of natural, physical and human resources were assessed using geomatics technology and village wise digital databases were generated which will form a potential baseline information in coastal area.

Keywords: Indian Ocean Tsunami 2004, DST Initiatives, Disaster Assessment, Mitigation.

Abstract

A very strong shallow focus submarine earthquake (of magnitude 9.0) occurred off the west coast of Sumatra Island due to the movement of Indian Plate and Burma Plate on 26th December 2004 at 06:18:53 IST. A vast area around its epicentre was rocked including Andaman and Nicobar Islands and parts of the eastern and western coasts of the Indian mainland. This earthquake had generated a global tsunami, which had also pounced on the Andaman and Nicobar Islands and the coasts of Andhra Pradesh, Tamil Nadu and Kerala and caused severe damage to the coastal population and infrastructure. Considering the devastation of this tsunamigenic earthquake, the Department of Science & Technology, Govt. of India has launched a coordinated programme for imparting S & T inputs with futuristic approach to support rehabilitation programme in the affected areas on a sustainable manner. The main objective of the programme is to generate geospatial databases on damages and risk zonation using pre and post-tsunami remote sensing (RS) data along with collateral attribute data in GIS platform. This paper speaks on the damage assessment (both natural / physical resources and human resources) caused by the earthquake and tsunami covering parts of Andaman Islands along with strategies for risk management and constraints and alternatives for micro level planning.

Keywords: Tsunamigenic earthquake, Damage Assessment, Remote Sensing and GIS, Andaman - Nicobar.

Abstract

A large tsunami triggered due to a massive earthquake of 9.3M in the offshore of Sumatra on 26^th December 2004 created havoc in several countries of the Indian Ocean. The deadly tsunami waves lashed the towns adjoining the coastline of several countries including Indonesia, Thailand, Malaysia, India and Sri Lanka causing more than 1,50,000 deaths. The earthquake occurred along the plate boundary is marked by a subduction zone between the Indian plate and the Burmese micro plate. In Andhra Pradesh, six coastal Districts were affected and amongst them four south coastal districts experienced maximum damage. In the present study, Tuppalapalem (vagarru revenue village) of Vakadu mandal, Nellore District was selected as a case study for discussion in the article. The objective of the study was to make an inventory of the damages to the natural and physical resources, by preparing pre and post-tsunami maps on geomorphology, land use / land cover, tsunami inundation and finally the tsunami risk zonation map on 1:8,000 scale. In this process, water and soil samples of the affected regions were also collected and chemical analysis was carried out. The data on damages were collected using a specially formulated data sheet. High resolution IKONOS data of January 2000 and IRS data of January 2005 were used for the generation of respectively the pre and post-tsunami geomorphology and land use / land cover maps. Ground truth data were also incorporated in these thematic maps.

The study has revealed that the water in all the bore wells became brackish after tsunami. About 80 country boats, 40 fibre boats and nets were lost with an estimated loss of about one crore. The tidal waters damaged the bunds of the aqua-farms and deposited the transported sediments in them. The extensive casuarina plantations, were reduced by the onslaught of tsunami and the casuarina trees became brown due to their contact with tidal waters. From amongst the various geomorphic units mapped in the study area, the beach, spits, shoals, creeks, swales, palaeo creeks were inundated by tsunami where as beach ridges, dune complexes and stabilized sand dunes were not affected and hence inferred as barriers. Geomorphology, land use / land cover and the tsunami inundation maps, tsunami risk zonation map were prepared showing very high, high and moderate zones of tsunami risks. It is recommended to take up casuarina plantations extensively along the coast as a biowall, which will also provide employment to the local people. The shallow aquifers of the coastal environment were contaminated by the tidal waves. Hence, drinking water should be supplied through protected water supply schemes. As a part of the community development, proper awareness must be created through training and appraisal to the fisherman community to face such natural disasters. The coastal regulation zone act, which prohibits any construction activity within 500m of the high tide line, should be strictly enforced. Keeping in view of the experience, a holistic tsunami protection plan is needed to safe guard the Indian coasts.

Abstract

The recent tsunami occurred on 26^thDecember 2004, caused great devastation along the east coast of Tamil Nadu, India. As the said tsunami has caused colossal damages, the impact assessment has become essential for tsunami mitigation measures. In this context, the extent of tsunami inundation, loss of lives, property loss and damages to physical and natural resources have been assessed in the tsunami affected area between Ennore and Mahabalipuram along the east coast of Tamil Nadu.

IRS LISS III PAN merged satellite data and IKONOS data were used for mapping the pre-tsunami geomorphology and land cover conditions and IRS-P6 PAN merged satellite data were used to map the post – tsunami terrain conditions including the inundations. From the study it is inferred that wherever buildings and population are denser the loss is more. Hence, vertical expansion may be needed as an alternative or to supplement horizontal expansion. Bio-shield along coastal areas, involving raising of mangrove forests, planting of casurina, salicornia, palms, bamboo and other tree species and halophytes which can grow near the sea will serve as speed-breakers for the up rising waves.

Keywords: Tsunami, Damage Assessment, Mitigation Measures, Chennai region.