eChapters

Theory

The energy available in food is expressed in unit is called joules or calories. One kilocalorie is equal to 4.184 kilojoules. The kilocalorie is defined as the amount of heat required to raise the temperature of 1 kg of water by 1°C. The calorific/ energy value of foods is usually determined using the instrument called bomb calorimeter. It is working based on the principles of calorimetry. Basically, this device burns a food sample and transfers the heat into a known mass of water. It measures the heat produced when the food sample is ignited by an electric spark in the presence of oxygen and platinum which acts as a catalyst. The quantity of food sample to be tested is placed inner part and known volume of water is taken in outer part of the bomb calorimeter. When the food sample is electrically ignited, the surrounding water absorbs the heat produced. The energy value of the food is calculated by measuring the rise in temperature of water.

I. Titrimetric Method of Estimating Salt in Fish Meal
(Modified AOAC, 1965 method)
Principle

The salt content is calculated as sodium chloride from the content of water solubles chlorides. The chlorides are dissolved in water and directly precipitated by titration with a silver nitrate solution using potassium chromate as an indicator.

Principle

When a sample of moisture and fat free feedstuff is boiled with dilute acid and then with dilute alkali, the soluble carbohydrates and proteins go into the solution and are extracted. The undissolved residue left behind represents cellulose, hemicellulose, lignin and mineral matter. The cellulose, hemicellulose and lignin put together are called crude fibre (CF). When the residue after drying and weighing is ignited, the fibre being organic in nature is burnt whereas the ash or mineral matter is left over. The fibre is obtained by deducting the weight of ash from the weight of the dried residue. In simple way it can also be explained that the crude fibre is determined gravimetrically as part of the substance which is left when protein, soluble carbohydrate, fat, ash and water have been removed.

In feeding of simple stomached animals, the analysis of crude fibre content is very essential because the amount of crude fibre predicts the digestibility of the feedstuff. Higher the fibre content lesser will be the digestibility.

Principle

Crude protein constitutes a mixture of true protein and non protein nitrogenous substances and is determined by estimating nitrogen and then multiplying the nitrogen content of feed by the factor 6.25.

The factor 6.25 is derived on the basis that all proteins contain 16% nitrogen. The total nitrogen content in the feedstuff is determined by Kjeldahl method which generally consists of three steps, i.e. digestion, distillation and titration. The sample is digested with an excess quantity of concentrated sulphuric acid which hydrolyses the protein, decomposes to ammonia and finally the ammonia combines with the excess of sulphuric acid forming ammonium sulphate. The acid digest is cooled, diluted with distilled water and distilled with strong alkali (sodium hydroxide, 40 per cent), the ammonia released during distillation is taken up into a boric acid solution forming ammonium borate complex and such ammonia is titrated with standard sulphuric acid. While estimating the nitrogen content, following reactions take place:

Objective

To determine the electrical conductivity (EC) of soil, which is an indicator of the soil’s salinity and its ability to conduct electricity. This provides valuable information about the nutrient availability and potential toxicity to plants.

Materials Required

• Soil sample

• Distilled water

• Electrical conductivity meter (EC meter)

• Beakers (100 mL)

• Measuring cylinder (50 mL)

• Stirring rod

• Filter paper and funnel

• Mortar and pestle (for soil grinding, if necessary)

The Electrical Conductivity (EC) of the soil is a measure of soluble salts present in the soil and is expressed as millimhos/cm or dSm^-1.

Principle

As the amount of the soluble salts in a solution increases, the electrical conductivity also increases. This electrical conductivity is measured in terms of resistance offered to the flow of current using a conductivity bridge.

It is known that solutions offer some resistance to the passage of current through them, depending upon the concentration of the soluble salts present. Hence, EC is measured in terms of electrical Resistance between parallel electrodes immersed in the soil water suspension.

In such a system, the solution between the electrodes becomes the electrical conductor to which the physical laws relating to resistance are applicable. The electrical resistance ‘R’ is directly proportional to the distance ‘L’ between the electrodes and inversely proportional to the cross sectional area ‘A’ of the conductor.

Accurate estimation of embryonic/foetal age play vital role in the developmental anatomy research related to morphogenesis and histogenesis of an organ or system. The observations and recordings of normal developmental features of embryos/ foetuses at successive stages of gestationare very important for studying functional development of an organ in anatomical research. The documentation of normal embryonic and fetal growth can serve as a guide for understanding the consequences of harmful influences at various stages of gestation (Evans and Sack, 1973). Post-mortem studies have provided valuable information on fetal development, identifying stages such as implantation, appearance of forelimb bud, tail development and hind limb development (Alberto et al., 2013). The normal development of external features of animals has been described by Evans and sack (1973), however, subjective assessment of foetal age from the external features alone is not much reliable, although it may be useful adjunct to more precise measurements (Richardson et al., 1990). For accurate estimation of developmental age, fetal measurements are needed which show a consistently rapid rate of growth and which are least variable at a given age (Richardson et al., 1990), however, these parameters are affected by individual variation and by breed differences within a species (Greenwood et al., 2005).
A number of methods have been discussed by many workers for estimation of age of foetus in animals. The method mainly focus on foetal biometry recorded either inside uterus during normal gestation process or after taking out foetus during post-mortem examination. In-utero foetal biometry allows estimating gestational age and time of parturition by ultrasonographic methods (Manning

(Method of Visek et al., 1953; Lueker and Lofgreen, 1961)

By using isotope dilution technique, It is possible to separate faecal calcium into endogenous and exogenous fractions. The true digestibility can be measured independently by making correction for faecal endogenous loss. The isotope dilution method described by Visek et al., (1953) involves daily intravenous injection of 45Ca for 15 days, followed by a collection of the serum and the faeces for 15 days. However, these numerous veinpunctures result in considerable discomfort to the animal. Lueker and Lofgreen (1961) modified this method in sheep by giving a single subcutaneous injection of 45Ca, followed by a collection of blood and the faeces for 7 days only.

The endogenous faecal calcium and true digestibility of calcium is calculated by the formula of Lofgreen and Kleiber (1954) as given below:

Principle
When a sample of feed, which is free from moisture, is extracted continuously with fat solvent like petroleum ether, the vapour from the ether boiling in the flask passes into the condenser where it condenses and drops back on the sample which dissolves ether soluble materials such as fat, sterols, lecithin, resins and volatile oils in the extraction flask. The extract is termed as crude fat or ether extract (EE) because it also contains other fat like substances in addition to true fat.

Equipment/glass wares
    1.     Analytical balance
    2.     Beaker
    3.     Cotton wool
    4.     Dessicator
    5.     Extraction thimble
    6.     Hot air oven
    7.     Oil flask (150-250 ml)

The ultrasonography is based on echo-principal i.e. reflection of sound waves. The ultrasound waves, commonly termed as ultrasound beam is generated from the pizzo-electric crystals, under electric stimulation. The sound beam travels and strike to the organs/tissues on its way and get either reflected or reabsorbed by these structures. The reflected beam is received back by the transducer, which are processed and displayed on the monitor of ultrasound scanner. The display of signal is in form of shades of grey scale i.e. from bright to black picture. If these sound beams strike to organ such as bone, then major part of the beam is reflected and it appears bright (white) on screen. If the sound waves strike to fluid, these get absorbed and are not reflected back, therefore, the image of fluid appears as black on the screen. Other organs appear in between black and bright white. In fact, the reflected sound beam is not proportionate to frequency and velocity of emitted ultrasound beam. The strength of ultrasound beam (grey scale) or brightness of the image depends upon the acoustic impedance of organ or tissue. In simple term acoustic impedance is the capacity of tissue or organ to reflect or absorb these sound beams that again depends upon density or composition of these structures. The reflection of sound beams also depends upon, the angle at which the ultrasound beam strikes the structure on its way. The distance of the organ from the transducer also affects image brightness.

Introduction

Access to adequate food, which is one of the fore-most basic needs of life, should be birthright of every single human being on this earth but in our country one fourth population is still underfed. The food insecurity situation is more rampant in the North-eastern region of the country. The proportion of population below poverty line (BPL) was reported at 31.4 per cent in Arunachal Pradesh, 34.0 per cent in Assam, 37.9 per cent in Manipur, 16.10 per cent in Meghalaya, 15.4 per cent in Mizoram, 8.8 per cent in Nagaland and 40.0 per cent in Tripura, in the year 2015 (RBI, 2015). At national lavel it was reported to be 37.20 per cent. By comparing BPL population in NE Region states and national level poverty it was found that several states of this region like Nagaland, Mizoram and Meghalaya were far better as in these states BPL percentage were very less than the national average, whereas in the states like Tripura, Manipur, Assam and Arunachal Pradesh BPL percentages were close to National level (37.20%). It has now been well established fact that the availability of food grains may not be the real problem of food security; it is prevailing poverty that comes in the way of achieving household’s food security. Hence, household food security is a function not only availability of food but also of the purchasing power of household. Any effort to achieve sustainable development demands concerted efforts to reduce poverty, including finding the solutions to hunger and malnutrition. In this study, an attempt has been made to analyze the status of food deprivation among fish farmers of West Tripura district of Tripura and to examine consumption expenditure behavior fish farming families of the study area.

22.1. Aim

To estimate the fruit firmness.

22.2. Apparatus/machineries/equipments required

• Magness Taylor Pressure Tester

• Penetrometer

22.3. Theory and principle

Fruit firmness is an important feature of maturity. During ripening, fruits may soften and become too soft at the overripe stage. The changes are detected by touching or by using devices like texture analyzers and pressure testers to measure texture of fruits and vegetable.

ABSTRACT

Coastal aquaculture in India is synonymous with shrimp culture since shrimp has a pronounced presence among the basket of commodities produced in the sector. In coastal aquaculture, maximum area is under shrimp culture due to its high profitability, ready marketability, premium price and unlimited export demand. Since the growth of shrimp has showed significant fluctuations in terms of area, production and productivity over time, this paper aims to seek and use appropriate methodology for computation of growth rates. Accordingly, the present study utilized nonparametric regression method for computation of growth rates. Results indicated that the methodology has been successful in extracting required information from the data set. The analysis revealed that growth of Indian shrimp farming is largely governed by east coast states. Potentiality of west coast states remains grossly underexploited. Broad results also indicate that growth rate is higher in commercial shrimp farming states compared to traditional farming states. Shrimp farming being a livelihood option for small and marginal farmers of the deprived sections of the population of a developing country, like India, consistent yield is more important than substantial growth in yield in shrimp farming.

Principle
If a sample of feed is heated and dried in a hot air oven at the temperature of boiling water (100°C ± 2°C), the water present in feed sample escapes as vapour. The loss in weight is considered as moisture and the residue is termed as dry matter (DM).

Requirement
    1.    Aluminium/steel moisture cup or Iron trey
    2.     Analytical balance
    3.     Dessicator
    4.     Hot air oven
    5.     Metal tongs
    6.     Spatula

24.1 Aim

To determine the moisture content in fresh and processed products

24.2 Theory

Estimation of moisture in fresh and processed fruit and vegetable products is important for evaluating their nutritive composition as well as to optimize method for their processing like drying, preparation of different products viz; jams, preserve, candies etc. Moisture is determined by drying the weighed sample to a constant weight in hot air oven and measuring the loss in weight to express the moisture content in percent. This method is used for estimation of moisture in all food products which do not decompose at 100ºC. Moisture content of some commodities (Table 4.1) is as under:

The estimation of moisture in foods is one of the most important and most widely used measurements in the processing and testing of food products. It is used to determine the nutritive value of food, to express results of analytical determinations on a uniform basis, and to meet compositional standards or food laws. The level of moisture in different fruits and vegetables varies widely. Most fresh fruits contain more than 85-90% moisture in edible portions. Broad range of moisture content in common fruit, vegetables and their products as general guideline are given in Table 3.1.
Estimation of Moisture content in food products: Moisture content in foods can be estimated by following methods.
i. By Drying in an oven
ii. By distillation with an immiscible solvent
iii. By Chemical and physical methods (Infra-red heating method)

Mycotoxins are toxic secondary metabolites produced by different types of moulds which are present in soil, plant and feed ingredients. Ingestion of toxins will result in reduced growth and production performance due to reduced nutrient utilization, illness or death of animals. Analysing the presence of mycotoxin and its concentration in grain and feeds is necessary to eliminate the adverse health effects of mycotoxins in animals. Estimation of mycotoxin in feed ingredients is a challenging task because the concentration of toxin is at µg/kg or parts-per billion levels. At the same time, analysing inappropriate samples is a waste of resources. Mycotoxins are not evenly distributed in feeds or grains. If the specimen collected for analysis includes contaminated grain, the mycotoxin will be detected. If not, the mycotoxin will not be detected.

Sample collection for mycotoxin analysis

The objective of sample collection is to collect the specimen samples from as many parts of the feed lot as possible. The size of the collected specimen depends on the size of the load received. Sample collecting probes can be used to collect the samples from bags.

Principle

Carbohydrates are divided into two groups i.e., crude fibre (CF) and nitrogen free extractives (NFE). The NFE comprises the sugars, starch and a large part of the material classed as hemicellulose.

The NFE is not determined by analytical procedures. This is calculated as the figure obtained when the sum of water, ash, protein, fat and crude fibre of a feed is subtracted from 100. Since the figure is determined by difference, it includes the cumulative errors of the other determinations and thus it is not an exact value.

Requirement

Following analysed volumes of a feedstuff are very much essential to derive the nitrogen free extractives of the same feedstuff.

Calculation
The nitrogen free extractives can be derived from the following formula:

[Titrimetric/ Walkley and Black (1934) Method]

Introduction

The role of soil organic matter, in relation to soil fertility and physical conditions, are widely recognized. The organic matter is the source of plant nutrients which are released inassimilable forms during microbial degradation. A major proportion of N (95 – 99 % of the total), P (33 – 67 % of the total) and S (75 % of the total) in soils occur in organic combinations, which mineralize to release the nutrients in inorganic forms to be used by plants. Nevertheless, it serves as a reservoir of plant nutrients, in promoting water storage, and in regulating microbial activity.

The organic matter content of a soil varies from 0.344 % in very sandy arid soils to more than 86 % in Peats and Mucks. Soil organic matter contains 5 % N, and 0.5 % each of P and S, thereby, having a N:P:S ratio of 10:1:1. The organic matter content of a soil is estimated by the amount of organic carbon (C) present, as this element represents, on an average, 52 – 58 % of the organic matter, and the C:N ratio is 10 – 15. In the sub-soil, the average organic carbon amount is 36 – 44 % (40 %), and the C:N ratio is < 8. In order to find out the amount of humified organic material, the organic carbon content is multiplied by 1.724, which represents the ratio between the humus and the organic carbon (100/58) and is known as the ‘von Bemmlen factor ’.

The organic matter content of soils is estimated from the organic carbon, determined by using the ‘Titrimetric method / Walkley and Black method. The Titrimetric determination, also known as the ‘wet-digestion method’ involves a rapid titration procedure for the estimation of organic carbon content of soils.

The cytological insult due to exposure of different environmental pollutant viz. pesticides, herbicides etc. impose great loss to the vitality and health of the individuals. The basic pathophysiological distrubances following the expo sure of these deterrents to the different visceral organs leads to dysfunction of these organs. Imbalance between body’s antioxidant defense and peroxidation of the lipid layer of cells’ causing free radical generation is defined as Oxidative stress. Free radicals are the molecules or entity that contains one or more than one unpaired electron. Pathophysiology of several diseases are associated with the generation of oxidative insult and many xenobiotics associated toxicity are also a result of oxidative damage and generation of reactive oxygen species and reactive nitrogen species. Alzheimer’s Disease is one of the fine example of oxidative damage associated neuronal degeneration.

Oxidative stress can be estimated using following parameters:

1. Lipid peroxidation (Paula et al., 2005)

2. Reduced glutathione (Sedlak and Lindsay, 1968)

3. Superoxide dismutase (Madesh and Balasubramanian, 1998)

4. Catalase (Aebi, 1983)

Sample Digestion

Dry ashing and wet oxidation are two widely adopted methods for releasing mineral elements from plant tissues. Dry ashing, typically conducted at temperatures between 550 and 600 °C, can lead to the loss of phosphorus (P) and potassium (K) through volatilization. This method is more time consuming and has several drawbacks, such as the volatilization of sulfur (S) and chlorine (Cl), which can be mitigated by adding sodium carbonate (Na2 CO3 ). Additionally, some phosphorus and micronutrients may become occluded during the process, making dry ashing less commonly used.

In contrast, wet oxidation employs oxidizing acids, such as a mixture of nitric acid and perchloric acid (HNO3-HClO4 ) or a tri-acid mixture of nitric acid, sulfuric acid, and perchloric acid (HNO3-H2 SO4-HClO4 ). The use of perchloric acid (HClO4 ) prevents the volatilization loss of potassium (K) and provides a clear solution, while sulfuric acid (H2 SO4 ) aids in completing the oxidation. Upon heating, perchloric acid dissociates into nascent chlorine and oxygen, enhancing the oxidation efficiency at high temperatures. However, direct contact between perchloric acid and plant samples can lead to explosions and f ires; thus, pre-digestion of samples is preferred.

Principle

Phosphorus is the chief acid forming mineral constituent of plant and feeds. Phosphorus present in the ash solution (Mineral extract) is precipitated as ammonium phosphomolybedate. The precipitate is washed with dilute potassium nitrate till free from acid and dissolved in a known excess of standard sodium hydroxide solution. The excess alkali is back titrated against standard acid to arrive at the exact quantity of standard solution required.

Objective: Estimation of photosynthetic pigment from plant leaves.

Material required: Plant leaves, test tube, test tube stand, spectrophotometer, balance, centrifuge machine, mortar and pestle, acetone and distilled water.

Theory: Photosynthetic pigments, namely, the chlorophylls are present in green leaves and shoots of plants. There are at least five types of chlorophylls in plants. Chl’a’ and ‘b’ occur in higher plants, ferns and mosses. Chl ‘c’,‘d’ and ‘e’ are found only in algae and in certain bacteria. Chlorophylls are extracted from plant leaves. The absorption peaks of chl ‘a’ at 663 nm and ‘b’ at 645 nm are characteristic measures from which amount of chlorophylls can be calculated.

The physical properties of seeds are a basic activity for designing processing equipments and precision planters. Since these characters vary with crop or variety, one needs to have the data handy to be used on shop floor. This data also helps to quantify processing efficiency, presence of dormancy and suitability for seed treatments for all existing and new crops or varieties.

INTRODUCTION

In nature water is considered as the most important natural resource which is utilized in large quantity throughout the world for drinking, washing, bathing, recreation, irrigation, aquaculture and many industries. Water also plays a fundamental role in regulation of water cycle in nature. India is a agriculture based country totally based on different water sources. The quality of water plays a important role to mankind because it is directly linked with human health. Lake water’s are mainly used for farming and domestic activities like cloth washing. Increasing human activities continuously in lake basins is posing a great threat to all forms of life in aquatic environment. Most of the people who live in villages use irrigation facilities for farms and use excessive use fertilizers and pesticides for agriculture purposes and subsequently and degrade the aquatic ecosystems of lakes. We need to conserve water for future generations and safeguard our natural resources for sustainable development and biodiversity conservation.

Many researchers investigated the freshwater lakes and ponds in the Indian subcontinent viz. Bagde and Verma (1985), Desai (2014), Patel and Patel (2012), Nirbhavanae and Khobragade (2017), Mehta et al (2016), Gupta (2018), Bastola (2013), Raj and Sevankodiyane (2018), Rana Phul Kunwar Singh (2016), Shyamala and Hemvathy (2018), Meshram et al (2014), Fule and Nimgare (2018), Chaudhary and Sitre (2020), Pimpalshende and Sitre (2021).

There are stages in seed supply chain where seed losses happen at harvesting and post harvest stage. These losses may occur due to higher moisture at harvest, due to harvesting methods, processing methods, at seed storage, during transport etc. Estimation of these losses is an important function of seed inventory management. Estimating seed losses help to improve processing and seed distribution efficiency. These simple statistical tools will help to measure quantitative post harvest seed losses. Seed testing can be used for measuring qualitative post harvest seed losses.

Vegetables form an important component of our daily diet as they provide necessary nutrients to the diet and they add colour, texture and flavour to it. Vegetables contain very high content of water (about 78 to 98%) and are reasonably good source of starch, sugar, cellulose, hemicellulose, pentosans and pectic substances. They also contribute minerals, vitamins and indigestible fibers to our diet. The yellow, orange and dark green leafy vegetables are rich source of carotenes- the precursors of vitamin A. Non-volatile acids, such as citric, malic, oxalic and succinic acids, contribute to their flavour. The very strong flavour characteristics of some vegetables like onion, garlic, cabbage, cauliflower, etc. are due to certain sulfur containing volatile compounds. However, vegetables, in general, are poor source of protein and amino acids.

India has made significant progress in the production of vegetables since independence because its diverse agro-climatic zones ranging from tropical to temperate allow the production of a wide spectrum of vegetables.At present, the country is producing about 108 million tonnes of vegetables and considered the second largest producer in the world (Venkatesan et al., 2006). Currently, the plant breeders are focusing their efforts to produce high yielding varieties having resistance against diseases and herbicides and tolerance against drought and salinity. Therefore, the physical aspects of quality, i.e., shape, size, texture, colour, tenderness, etc. are given due priority in the breeding programme with no emphasis to the biochemical and nutritional quality parameters, which include dry matter, proteins, vitamins, sugars, flavouring compounds, alkaloids, flavonoids, etc. However, under present set up of World Trade Organization (WTO), the country will have to compete with quality conscious European and developed countries, and with inferior quality product, it would not be possible to penetrate the foreign market. Therefore, breeding programme in a country like India with future-plans of globalization of agriculture produce must be aimed at achieving good nutritional quality. In different types of vegetable, a varied set of biochemical parameters determines the quality. In this chapter, the methods for qualitative and quantitative determination of these parameters in vegetables have been described.

Principle

    Inorganic salts are relativity insoluble in aromatic solvents which has been detrimental to the estimation of 45Calcium by scintillation counting. This technique inolves the counting of 45Calcium as calcium 2-ethyl hexanoate in a solution of toluene phosphor; and the counting as calcium chloride in a tertiary mixture of absolute ethyl alcohol-hydrochloric acid-toluene-phosphor.

Reagents
    1.    ⁴⁵Calcium. A ⁴⁵Calcium solution supplied as calcium chloride in hydrochloric acid solution, is suitably diluted.
    2.    Calcium chloride, 0.045 N, is prepared by dissolving ACS grade calcium carbonate, dried to constant weight at 110ºC, in 5 N hydrochloric acid.
    3.    Calcium acetate, citrate, lactate, acid phosphate, chloride and hydroxide.
    4.    Ammonium oxalate solution, 4 percent
    5.    2-Ethyl-hexanoic acid.
    6.    Toluene-diphenyloxazole solution, 2g of diphenyloxazole are dissolved in 500 ml of toluene.

When there is indication of linkage from F or testcross data through significant deviation from 9: 3: 3: 1 and 1: 1: 1: 1 ratio, it is implied that independent assortment is not taking place and this is taken as an indication of linkage. The inverse of linkage strength is the recombination value and is often symbolized by ‘p’ whose maximum value is 50% because out of four strands of a tetrad, two are always parental types and two are recombinant types when all the cells show crossing over.

In spite of its high protein (CP, 34-36%) content, castor bean meal as such is not used as livestock feed due to the presence of toxic factors viz., ricin, ricinine and allergen. Of the three, ricin is the most detrimental to animals. In order to detoxify the castor cake, a number of physical and chemical methods are employed. The efficacy of the treatments is assessed, based on the qualitative and quantitative changes in ricin content. Of all the detoxification methods, autoclaving (15 p.s.i., 60 min) and lime (4% w/w) treatments completely destroy the toxin. (Anandan et. al., 2005).

Estimation of Ricin

The raw and detoxified samples can be analysed for the toxin, ricin as per the method of Kabat et al. (1947) with modifications as suggested by Waller and Negi (1958).

Extraction of Ricin

The solvent extracted castor cake sample of 500 g is extracted with 2.5 l of water acidified with HCl to a pH of 3.8 by shaking the contents in a conical flask for 6 h. The contents are allowed to settle and are then filtered trough Whatman filter paper No.1 . The residue is treated with 1.5 l of distilled water, shaken for 3 h and filtered through the same paper. A second treatment with water is given to the residue and filtered again through the same filterpaper.

This filtrate contains all the ricin and portions of ricinine that are soluble in cold, dilute HCI. It is evaporated to a small volume by vacuum distillation below 40 °C. The filtrate is saturated with sodium chloride and centrifuged at 4000 rpm for 20 min. to separate the precipitate containing only ricin.

Principle

In this method the estimation of pentose sugar is carried out. Acid hydrolysis of RNA releases ribose (a pentose sugar) which in the presence of strong acid undergoes dehydration to yield furfural. Orcinol, in the presence of ferric chloride as a catalyst, reacts with furfural producing a green colored compound which can be quantitatively estimated at A_{665 nm}. DNA gives a limited positive reaction with Orcinol test.

Materials and Reagents

1. Spectrophotometer
2. Boiling water bath
3. 5% chloroform (HClO₄)
4. Standard RNA solution : Dissolve yeast RNA (500ìg/ml) in 5% HClO₄ . make different dilutions to obtain solutions containing 100 – 500ìg RNA/ml with 5% HClO₄ .
5. Orcinol reagent : Dissolve 100mg of ferric chloride (FeCl₃.6H₂O) in 100 ml of concentration HCl and then add 3.5 ml of 6% solution of Orcinol prepared in alcohol.

Introduction

In India, the ground water recharge in arid and semi-arid regions is very important particularly as most of the population residing in these regions depend on groundwater for drinking and irrigation purposes. In such scenarios, to alleviate the problems of drinking water, the collection and storage of rainwater to supplement existing water supply sources should be implemented. The utilization of rainwater is one of the best methods that can aid in sustainable urban development (Kim et al., 2005). Every drop of rainfall should be utilized to cater the demand of an ever increasing population as the present system of water supply may not be sufficient in future. The rain water collection & its utilization, seems to be the only option to satisfy the demand of arid and semi arid regions. In most cases, the rain water is the purest water source & contains very low impurities. It is necessary to adopt rainwater harvesting methods in places where the conventional water supply has failed to meet the peak period demand of the people for drinking water. Rain water harvesting is one of the most economical and practical methods to provide supplementary water supplies for drinking purpose.

Principle

Nucleic acids leaving the rumen are mainly of microbial origin which are extensively digested in the small intestine and the purines liberated are absorbed. Only a small amount of absorbed purines are utilized by the host animal, the rest are metabolised forming hypoxanthine, xanthine, uric acid and allantoin. These metabolites are excreted mainly through urine. Therefore, with the understanding of how urinary excretion of purine derivatives (PD) respond to purine absorption i.e. the response curve of PD excretion to purine input into intestines, the microbial purine outflow from the rumen and the microbial N supply to the ruminant animal can be estimated by measuring the purine derivatives excretion through urine.

(Method of Hyden 1955a,b)
I. Use of Polyethylene Glycol (PEG)

These compounds are manufactured through the reaction of ethylene oxide with water, ethylene glycol or diethylene glycol to furnish functional  groups (in this case hydroxyl) for the propagation of the reaction. The process results in a mixture of diols of different chain lengths, in which the numbers of molecules of various sizes are presumed to be represented by Poisson’s distribution (Shaffer, Critchfield and Nair, 1950b). Polyethylene glycols 200, 300, 400 and 600 are fluids: compounds 1,000, 1,500, 4000, 6000 and 1,0000 are solids of increasing firmness. PEG compounds of molecular weight above 1000 are not absorbed from the gastrointestinal tract of the rat and man.

Polyethylene glycol has been used frequently as a water soluble marker in studies of absorption in man and animals (Sperber et al., 1953; Hyden, 1955a,b; Corbett et al., 1956; Gray et al., 1960; Weller et al., 1962; Ulyatt, 1964a,b; Walker and Hawley, 1965; Tulloh et al., 1965; Sinha et al., 1970; Nagel and Piatkowshi, 1972).

30.1. Aim

To estimate the salt contents in given samples by using Mohr method.

30.2. Theory and principle

Common salt is used during preparation of pickles, sauces, ketchup, fruit chutney and appetizers. Besides, imparting taste, the salt in appropriate concentration also acts as a preservative. In different products, it is estimated by using Mohr method. The sample is titrated with standard solution of silver nitrate for estimation of salt by using potassium chromate as an indicator. From the titre the concentration of salt is estimated by using a standard expression.

Sample Digestion

Dry ashing and wet oxidation are the two widely adopted methods for the release of mineral elements from plant tissues. Dry ashing is carried out usually at an ignition of 550 to 600 °C leads to loss of P and K by volatilization. Dry ashing being comparatively more time taking and also has a few drawbacks (such as S and Cl is lost by volatilization during ignition which can be prevented by adding Na2 CO3 ; a part of P and micronutrients also get occluded) is hence occasionally adopted. On the other hand, wet oxidation employs oxidizing acids like HNO3-HClO4 di-acid or HNO3-H2 SO4-HClO4 tri-acid mixture. The volatilization loss of K is prevented by the use of HClO4 and provides a clear solution while H2 SO4 helps completing oxidation. On heating HClO4 dissociates into nascent chlorine and oxygen, increasing the oxidation efficiency at high temperature. Explosion and fire may occur if there is direct contact of HClO4 with plant sample; hence the pre-digestion of samples is preferred. Digestion with HNO3-HClO4 instead of tri-acid mixture is also adopted specially when S is also to be determined in the same digest. The wet oxidation method being less time-consuming, easier and convenient is given below:

The levels of calcium (Ca), inorganic phosphorus (P) and magnesium (Mg) may help in early diagnosis of metabolic and deficiency disorders and for monitoring the herd health status of dairy cattle to maintain production and reproduction.

Estimation of Serum calcium

Calcium is present in 2 forms – inorganic and organic forms. Most of the functions of the calcium depend upon the ionized form. For estimation of serum calcium the most commonly used method is Clark and Collip method.

Sodium and potassium are the most important electrolytes of the body fluid. The sodium as sodium chloride is contained in body fluids. The potassium is also essential in body fluids and its concentration is controlled by the kidneys. The estimation of sodium-potassium balance makes an important contribution as component of metabolic profile test. Low level of Na occurs in early lactation of low grazing on summer pasture and also increasing age, depraved appetite, polydipsia and polyurea.

Total protein: (Biuret method)

There are several methods of estimating protein, in food, agricultural and clinical samples, each of them varying in sensitivity and applicability.

Principle
Biuret method is highly specific for protein and is based on the formation of the blue peptide-copper complex in alkaline solution. It is a method of choice in the clinical laboratory because of the simplicity accuracy and precision. The major limitation of the method is its poor sensitivity for many dilute solutions. The principle of this method is that the peptide bonds in protein react with biuret reagent to give a violet colored complex known as cupric potassium biuret. The colour intensity of which is proportional to protein concentration.

Abstract

The study of size, shape and pattern of various bones in the skull of vertebrate fossils constitutes the foundation of their taxonomy and plays a role in understanding their evolution as well. Size and shape change during lifetime, and the growth of an individual bone involves both isotropic enlargement of its boundary due to uniform growth and differential enlargement that changes its shape. This paper attempts to develop a methodology for quantitative assessment of the pattern of ontogenic shape changes for all the individual skull roof bones of a taxon (Benthosuchus) of an extinct amphibian (temnospondyl) from the Lower Triassic of Russia. Published diagrams depicting skulls of different ontogenic stages have been used. A measure for the degree of shape changes is also proposed. In this study, the skull roof bones in dorsal view were represented as polygons. The boundary of each polygon of a juvenile skull was compared with that of an adult. For comparative purpose, the polygons of the younger skull were placed optimally inside that of the older skull, under the assumption of maximised uniform (isotropic) growth. The variance of the distances between the two boundaries measured at a number of points along the boundaries was considered as a measure for the degree of shape change. The results obtained are in partial concurrence with the published observations traditionally obtained from anatomical studies for the above mentioned growth series.

31.1. Aim

To estimate the sodium benzoate contents in fruit and vegetable products.

31.2. Theory and Principle

Sodium benzoate is used as a class II preservative in preservation of pickles, sauces, squashes etc. Its estimation is important as the quantity of class II preservative shall not exceed maximum limit prescribed under FSSAI. In a sample containing NaCl, the benzoic acid is converted into water soluble sodium benzoate by addition of NaOH. When the Sodium benzoate solution is acidified with excess of HCl, water insoluble benzoic acid is formed which is extracted with chloroform. The chloroform is removed by evaporation and the residue containing benzoic acid is dissolved in alcohol and then titrated with standard sodium hydroxide.

Aim

To estimate the soil loss using universal soil loss equation

Universal soil loss equation

Wischmeir and Smith (1962) has been developed a predictive equation for estimating the soil loss taking into account following factors: Climatic characteristics, soil characteristics, crop management and conservation practices. It is called Universal soil-loss equation (USLE).

The Walkley-Black method is a widely used chemical procedure to estimate soil organic carbon (SOC). It involves the oxidation of organic carbon by potassium dichromate in the presence of sulfuric acid, followed by titration to determine the amount of unreacted dichromate. Here is a detailed step-by-step guide:

Materials Required

• Soil sample (air-dried and sieved through a 2 mm sieve)

• Potassium dichromate solution (1 N)

• Concentrated sulfuric acid (H2 SO4 )

• Ferrous ammonium sulfate solution (0.5 N)

• Orthophosphoric acid (H3 PO4 ) (optional)

• Diphenylamine indicator or N-phenylanthranilic acid (indicator)

• Distilled water

• Burette, pipette, and conical flasks

• Heating mantle or hot plate

The pH is defined as negative logarithm of hydrogen ion concentration or the log of the reciprocal of the hydrogen ion concentration (Sorenson, 1906).

Principle

A glass electrode in contact with hydrogen ions of the solution acquires an electric potential which depends on the concentration of hydrogen ions. This is measured potentiometrically against some reference electrode which is usually a calomel electrode. The potential difference between glass electrode and calomel electrode is expressed in pH units.

Two electrodes are used in the determination of pH. One is reference electrode which provides a standard voltage and is usually a saturated calomel electrode which has two layers of saturated solution of KCl and mixture of solid HgCl₂ and Hg. The outer tube is usually 5-15 cm long, 0.5-1 cm in diameter. The mixture of solid HgCl₂ + Hg paste is contained in an inner tube that is connected to the saturated KCl solution in the outer tube by means of small opening. The resistance developed by this type of electrode is 2000-3000 Ohms.

The outer electrode is glass electrode that consists of a tube enclosing a lead wire made up of Ag coated with AgCl. This wire is again enclosed in a wax insulation. To the tube at the bottom is attached a glass bulb made up of a special kind of glass which is sensitive to hydrogen ions. The thickness of the glass membrane varies from 0.03 to 0.1 mm and has a resistance of 50 to 500 mega Ohms.

When these electrodes are dipped in solution, the saturated solution of KCl comes out of reference through small holes and forms an invisible ionic bridge between electrodes through which current passes. The hydrogen ions are absorbed by glass electrode and depending upon the amount of hydrogen ions present in the solution, an electric potential develops between electrodes. This potential difference is measured in terms of pH units by suitable Galvanometer.

Object: Estimation of stomatal index and stomatal frequency with replica method.

Material required: Leaf sample, blue/red correction fluid, transparent finger nail polish, brush glass slide and microscope.

Principle: The number of stomata per unit area of the leaf is called as Stomatal Frequency. The stomatal index is defined as the percentage number of Stomata as compared to all the epidermal cells in a unit area of leaf i.e.

28.1. Aim

Estimation of reducing sugars in fresh fruits and processed products using Lane and Eynon method.

28.2. Theory

Sugars are inherently present in different fruits and vegetables or added during preparation of different products. They are added to the fruit products to improve the taste and also to act as a preservative. Glucose and fructose in the fruits represent reducing sugars while sucrose or cane sugar added represents the non-reducing sugar. They are estimated by using Lane and Eynon method which measures sugar as reducing sugar and total sugar as invert sugar.

32.1. Aim

To estimate the level of sulphur dioxide contents in fruit and vegetable products

32.2. Theory and principle

Sulphur dioxide in food product is added as class II preservative and may exists as undissociated sulphurous acid, as free bisulphate or sulphite ions or as combined SO2 in the form of hydroxy sulphonates. Sulphur dioxide is measured as free or total SO2. Estimation of SO2 in squashes, jam, RTS drinks is important as its presence beyond the prescribed FSSAI limits make the product not confirming to Indian Food Laws. Generally 2 parts of KMS (Potassium metabisulphite) releases one part of SO2 explained as under:

27.1. Aim

To estimate the titratable acidity of fresh and processed fruit and vegetable products.

27.2. Theory

Most of the fruit, vegetables and their products contain acid or mixture of acids. The acids may occur naturally in the fruit and vegetables or may be added during manufacture of different products or by lactic acid or acetic acid fermentation. Generally citric acid is added in most fruit products while in pickles, sauces and ketchup acetic acid is used. The acids are mainly responsible for the tartness or sour taste, thus estimation of acidity is used as the measure of tartness. They also help in preservation by lowering the pH of the finished products.

Principle
Total ash is the inorganic residue which remains after a feed stuff is ignited to carbon free at 550-600oC in a muffle furnace. In other words, ash is that part of the material which does not disappear at 550-600ºC, while all the organic matter (OM) gets burnet.

Requirement
    1.    Analytical balance
    2.     Asbestos sheet
    3.     Dessicator
    4.     Heater /gas flame burner
    5.     Metal tongs
    6.     Muffle furnace
    7.     Silica basin/crucibles

(Method of Saryre, 1963 and IAEA, 1969)
Introduction

This technique helps in detection of very small amount of stable elements in fairly large quantitites of extraneous matter. Trace elements like zinc, copper, molybdenum and arsenic which exist in minute amounts in certain organs or tissues. For example, to detect the amount of copper present in one gram of tissue. using 1 mg of thin copper foil as control. Normal copper contains 69 percent ⁶³Cu and 31 percent ⁶⁵Cu. The (n,r) reactions on these two stable isotope produce ⁶⁴Cu and ⁶⁶Cu respectively. The half life of ⁶⁴Cu is 12.8 h and that of ⁶⁶Cu is five minutes. Therefore the latter can be ignored, if more than that an hour elapses between the end of the irradiation and the measurement. The specific activity of the unknown separate is compared with that of the known standard separate, and the content of Cu in the original tissue sample is thereby calculated.