eChapters

Introduction

Measurement of pH of a solution and preparation of different types/strength of buffers are common practices in a laboratory, particularly in the Biochemistry and Molecular Biology laboratories. Therefore, in this chapter you will be acquainted with the procedures of measuring pH of a solution as well as preparation of some of the commonly used buffers in a laboratory.

Potential or Power of Hydrogen Ion (pH)

Measurement of pH of a solution is measuring the molar concentration of hydrogen ion [H+] in the solution, which is an indication of the acidity or basicity of the solution. The symbol pH stands for “power of hydrogen” and numerical value for pH is just the negative logarithm of the molar concentration of hydrogen ions [H+]. The ionic product of water (Kw ) is the basis for the pH scale. The total hydrogen ion concentration from all the sources and it can be experimentally measured.

The pH scale designates the concentration of H+ (and thus of OH−) in an aqueous solution, which ranges between 1.0 M H+ and 1.0 M OH−. The term pH is defined by the expression

Thus, the ionic product of water makes it possible to calculate the concentration of H+, with given concentration of OH−, and vice versa. The value of 7 for pH of a neutral solution is not an arbitrarily chosen figure; it is derived from the absolute value of the ionic product of water. A solution having pH greater than 7 is basic, and the concentration of OH− is greater than that of H+. A solution having a pH less than 7 is acidic.

Introduction
• A cell is the most basic structural and functional unit of life. These are of two types:
i) Prokaryotic cells– Prokaryotes are those cells which lack a membrane bound nucleus and other membrane bound cell organelles. These cells are primitive cells. Examples, bacterial cells, archaeal cells.
ii) Eukaryotic cells– Eukaryotes are those cells which have distinct membrane bound organelles. These are advanced cells. Example, animal cells, plant cells, fungi.
• A microorganisms (from the Greek: mikros, “small” and organism’s, “organism”) are those small living organisms which cannot be seen with naked eyes. These are of two types:
i) Single cell– Organism made up of a single cell.
ii) Multi-cellular– Organism made up of multiple cells.
Shape and Arrangement of Bacterial Cells
• Prokaryotes display following shapes
• Spherical cells called Cocci
• Cylinders called rods or Bacilli
• Coma shaped called Vibrio
 

Meat and Meat Products

    1.    Meat can be defined as “the muscle tissue of slaughter animals”.
    2.    meat is composed of water, fat, protein, minerals and a small proportion of carbohydrate

• The proportion of bone varies depending on breed and body condition from 12 to 28% in the dressed carcase and approximately 15% in a good large ruminants carcase
• Bone percentage increases with the age and weight of the animal and it is lowest in Aberdeen Angus cattle and it may increase to 28% in low quality large ruminants
• The average bone % in bobby calves is 50%, veal calves 25%, in lamb 17–35%, in pork 12–20% and in poultry 8–17% Important parts of digestive system of meat animals Ox tongue
• Filiform papillae found on the tongue are pointing backward and horny and thus, helps in food prehension
• Actinobacillosis erodes the prominent posterior part of the tongue dorsum
• 10–14 circumvallate papillae are spread in the region of prominent dorsum around the either side of the tongue midline
• Black pigmentation of the tongue surface is fairly normal and not associated with any disease condition
Sheep and goat tongue
• Similar to cattle tongue
• However, papillae are not horny but the centre of the tip is slightly grooved
• Black pigmentation of the surface of the tongue is common in blackskinned sheep.

(Ref: 1997-2016 American Meat Science Association)
The methods used for cooking meat can be divided into two groups:
1. Dry heat methods
2. Moist heat methods

6.1 Introduction

The food industry produces large volumes of waste both solid and liquid, starting from the initial step of raw material to the final consumption of processed food. Apart from a loss of valuable biomass and nutrients, the generated waste poses increased disposal and potentially severe pollution problems. Meat and meat industry is no exception where slaughter houses, meat processors, wholesalers and rendering plant generates huge amount of waste [1, 2].

Meat and meat processing industry, is among the least profitable industries despite its immense size and large gross sales. Effective recovery and utilization of by-products and wastes is the lifeline of meat and poultry processing industry. Thus, it becomes imperative that an effort be made to reduce expenses by employing the use of new or modified processing methods and through in-plant treatment, where waste effluents and by-products could be recovered and often upgraded to useful products of higher value. Meat processing wastes have a potential for recycling raw materials or for conversion into useful products of higher value as by-product or even as raw material for other industries or for use as food or feed after biological treatment.

Abstract

The interest in the utilization of industrial by-products is increasing day by day and is major reason for exploring different meat, poultry and fish industry waste and optimization of extracting conditions of different valuable compounds. Utilization of these by-products in effective manner can be positive for meat industry economy as well as environmental pollution of the country. Besides the potential revenue losses, non-utilized or underutilized by-products accounts for the extra cost for their disposal. Meat producers are converting these by-products into value added edible and inedible form. Among the most prominent current uses of meat, poultry and fish waste are food ingredients, water treatment, cosmetic and personal care products, biogas/biodiesel, biomedical and pharmaceutical application. Several studies have dealt with the production of several value-added products such as gelatin, collagen, enzymes, specific proteins, bioactive peptides, chitin, chitosan, and pigments fro m the meat industries waste. Recently, in the food and pharmaceutical industry, an increasing number of new applications have been found for products generated from meat, poultry and fish industry waste; in different products as foaming agents, emulsifiers, biodegradable film-forming materials, colloid stabilizers, and microencapsulating agents, in line with the growing trend to replace synthetic agents with more natural ones.

INTRODUCTION

Meat is the flesh of animals that is used for food and consists of muscle, fat and bone. If the muscle which is commonly known as the lean meat, is examined under the microscope, it is seen to be made up of bundles of fibers held together by a thin membrane called connective tissue. Further study reveals that these fibers are in readily hollow tubes that vary in length in different animals and in different muscles in the same animals that are filled with a fluid, sometimes called muscle juice, which is known to contain protein, minerals and extractives. The forms of protein in the muscles are myosin (a globulin) and myogen (an albumen) and in addition, on red meats, hemoglobin.

The biofilm formation is usually assayed by using Congo Red Agar (CRA) plate test. According to a method developed by Freeman et al., (1989) the isolates are stored in nutrient agar slants and screened for biofilm formation ability using CRA plates. Biofilm forming strains are observed as dark black colonies while others as red colonies on the CRA plates. Recently, the concept of these biofims have changed with new imaging technologies, biochemical methods and molecular ecosystem biology tools. A biofilm structure can be observed in 3-D form to the nano-scale level (Neu and Lawrence, 2015). A lot of studies are being conducted on the physiology of the biofilm cells, the genotypic and phenotypic variation among the biofilm community, as well as the biofilm metabolome, proteome and transcriptome (Raes and Bork, 2008). This will help in the the development of efficient methods to control deleterious biofilms (clinical biofilms, food contaminants, biofouling on industrial equipment and on ship hulls) and to enhance and modulate beneficial ones

The lack of mechanistic understanding of probiotic activity is a major drawback for the prediction of safety of probiotic intervention. The complex gut-associated microbial ecosystem and nutritionally related factors are the most important environmental triggers for the development and modification of chronic degenerative diseases including immune and metabolic pathologies. In fact, the interaction between the gut microbial ecosystem and the host is considered to be a critical factor in overall health or disease. Whether probiotics will exert protective, harmful, immune-stimulating or immune-suppressing effects on a host is dependent on the interaction between the microbial signals, the genetic make-up of the host and the effects by the environment. Many studies have revealed that certain probiotic bacteria stimulate immune cell proliferation and activity as evidenced by the production of cytokines and antibodies, thereby enhancing the effectiveness of the immune response against pathogens. Ng et al. (2009)

Labour is one of the biggest input costs for vegetable growers. Vegetable farming is labor intensive and time consuming. Frequently, it is associated with low yield and poor quality production. The constraints are high labor requirements for land clearing, ploughing, bed forming, mulch laying, seeding, transplanting, harvesting and transporting. Mechanization is interjection of improved tools, implements, machines and other equipments between man and materials (soil, water, environment, seed, fertilizer, pesticides, growth regulators, irrigation water, agricultural produce and by-products such as fruits, vegetables, and seeds, etc.)

A large number of people in developing countries have traditionally depends on products derived from plants, especially from forests, for curing human and livestock ailments. Additionally, several aromatic plants are popular for domestic and commercial uses. Collectively they are called medicinal and aromatic plants (MAPs). About 12.5% of the 4,22,000 plant species documented worldwide are reported to have medicinal values. With dwindling supplies from natural sources and increasing global demand, the medicinal and aromatic plants, will need to be cultivated to ensure their regular supply for processing and value added products.

The term “Medicinal and Aromatic plants” generally denotes those non-aromatic and aromatic plants, which are used for medicinal, perfumery, dye and cosmetic purposes. They are rich in secondary metabolites and are potential sources of drugs. Generally the whole plant roots, stem, bark, leaves, flowers, fruits, gums and oleoresins, etc. are used.

India has been considered as treasure house of valuable medicinal and aromatic plant species. Ministry of Environment and Forests have identified and documented over 9500 plant species considering their importance in the pharmaceutical industry. In the present context of ‘back to nature’ in health care, it is relevant that these valuable plant species are not only preserved but also their cultivation developed in order to meet the entire demand of the domestic industries as also to exploit the bright prospect for export. Shift from collection to cultivation of medicinal & aromatic plants will also ensure purity, authenticity and sustainable supply of raw materials required for herbal drugs, including polyherbals.

Membrane technology is a proven separation method used on the molecular and ionic levels. Since the beginning of the 1970s, this technique has been adopted by the dairy industry. Membrane separation is widely used in dairy processing plants to perform an ever-increasing range of duties, e.g. pre-concentration, partial demineralization, protein separation, bacteria removal, brine clarification and waste water recycling. Representing one of the great technological developments occurring within the dairy industry during the second half of the twentieth century, progress was driven initially by the transfer of know-how gleaned from the application of cellulose acetate-based reverse osmosis (RO) and ultrafiltration (UF) membranes in other industrial sectors to whey processing. Later, new membrane materials and engineering designs were built on this initial achievement and opened up further opportunities for the application of the full spectrum of membrane separation systems that also includes Nan filtration (NF) and cross-flow microfiltration The integration of these unit operations into traditional dairy processes has led to the development of innovative ingredients as well as improvements in yield, efficiency and product quality. R & D work indicates potential RO application for concentration of milk for products like khoa, condensed and dried milk products and of UF application for the manufacture of shrikhand, paneer, chana and cheese. Application of these processes permits higher energy saving, higher yields and superior product quality compared to traditional processes of thermal evaporation.

1. Introduction

Pulpy and juicy fruits like orange, guava, banana, grape, mango, papaya, pears, apples and jackfruit can be converted into fruit products like squashes, juices, cordials and ready-to-serve (RTS) fruit beverages. These RTS fruit beverages are both refreshing and thirst quenching and have become very popular. Liquid fruits are the clarified juices prepared from these pulpy and juicy fruits. There is a demand for liquid fruits in the international market for various applications. The liquid fruits can be used as a natural alternative to synthetic beverages. They can be suitably concentrated or diluted, blended with other juices and also can be carbonated as fruit based soft drinks. Removals of pulpy material from the juices make them easier to preserve by pasteurization and are amenable to carbonation. Pulpy fruits can be successfully processed into liquid fruits (clarified juices) by using pectic enzymes. The emphasis of the fruit juice processing industry has, so far, been mainly on conventional clarification processes like enzymatic and chemical treatments followed by filtration using filter aids; and concentration by vacuum evaporation.

1. Introduction

Membranes separation processes have gained widespread applications in food industry. High selectivity of membrane has been exploited for separating a particular component from complex liquid food mixture and for controlled release of active ingredients like preservatives or flavor compounds. Today, a number of chemical processes utilizing the unique properties of membrane have been developed for commercial application in food industry with specific advantage of low energy requirement. Membrane separation/molecular sieving is one among those food engineering principals which has found broad range of applications including concentration of heat labile compounds, recovery of solvent, downstream processing, flavor volatile recovery, deacidification, desalination, waste water treatment etc

Introduction

Since 1990, there has been a lot of interest in functional foods and nutraceuticals, particularly because of their impact effects on human health and the prevention of certain diseases. Apart from growing good quality natural products, there are challenges in extracting, refining, analyzing active ingredients, and evaluating safety before an effective, reliable product is made [1,2]. Special attention needs to be focused on separation and purification mainly because 40-80% of the cost of production is assigned to separation and purification unit operations in making functional foods and nutraceuticals. There are also several carotenoids and polyphenol products that have been identified from various plants and a single plant could contain highly complex profiles of these compounds. These are labile to heat, air, and light, and they may exist at low concentrations in the plants. This makes the separation and detection of nutraceuticals a challenging task. The membrane techniques used for the separation of nutraceuticals from the natural products, as well as their applications and influencing factors are discussed in this chapter [3, 4].

6.1 Metabolism
Dietary components like carbohydrates, lipids, and proteins are continuously broken down and synthesized through various chemical reactions (exergonic or endergonic) that are concerned with energy. These processes not only break them down but also interconvert them for their synthesis. Dietary components, when utilized, are known as nutrients the body. The number of reactions occurring in living cells maintains the body cells and fluid’s homeostasis and dynamic status. To keep the dynamic state of a cell, many reactions are going on to synthesize or break down the different types and sizes of molecules. The total of these reactions is known as metabolism.
The metabolism may be anabolic or catabolic. Further, it may be aerobic or anaerobic, depending on oxygen availability. These four terms are explained below:
I. Aerobic and Anaerobic Metabolism
• Aerobic metabolism-- In aerobic metabolism, the carbohydrates (substrate) in the presence of oxygen are metabolized to release energy, carbon dioxide, and water. The released energy is converted to ATP by two processes in the mitochondria (the Krebs cycle and oxidative phosphorylation). In oxidation, the electrons released from a glucose molecule are transferred to reduced NAD+ and FAD. The oxygen (electron acceptor) is reduced to water. Water formation [from H2(g) and O2(g)] is an exothermic reaction. The energy released from the chemical bond of glucose is captured as ATP, and heat is released.

Milk, commonly referred to as the “ideal food,” is an essential source of nutrition for human consumption. Because of the growing human population and the rising demand for milk and milk products, there is more interest in and concern about the quality and safety of dairy products. Milk comprises chemical substances with various functions in the human body, such as carbohydrates, lipids, proteins, and trace elements (vitamins, minerals, etc.) (Guetouache et al., 2014).

4.1. Introduction

Packaging of materials protects, surrounds, and contains food products. It is necessary from processing and manufacturing stage till the final consumption through storage and handling. In 1804, Nicolas Appert, a French confectioner, discovered a method of “conserving all kinds of food substances in containers.” In 1810, the Ministry of the Interior’s Bureau of Arts and Manufactures paid Appert an ex-gratia payment of 12,000 francs on the condition that he publish the details of his process. Appert avoided the use of tinplate in his study. However, in the early nineteenth century (1810), Phillipe de Girard, a French inventor, filed a patent referring to the replacement of glass jars and bottles with tin cases. The official confirmation in the New York Evening Post on July 18, 1822 by Daggett and Kensett is thought to be America’s first offering of preserved provisions in tin cans (Bishop, 1978). Table 1 shows the evolution of metal packaging materials at various stages.

Methylene-cyclo-propyl-glycine (MCPG), is a cyclopropyl derivative, grouped into the amino acids that have been isolated from the higher plants (Fowden, 1960). MCPG was identified to be closely related to two other cyclopropyl derivatives (Fig. 1), 1-aminocyclopropane – 1 – carboxylic acid from Vacciniumvitis-idaea and perry pears (Vahatalo and Viertanen, 1957; Burroughs, 1957) and â- methylenecyclopropyl alanine (MCPA or Hypoglycin A) from Blighia sapida (Hassall and Rayle, 1955; Anderson et al., 1958; Ellington, Hassall and Plimmer, 1958).

Several attempts have been made to detect the biopotentials of microorganisms with reference to their ability to produce various enzymes with a view to use them in industrial processes and bioremediation applications. Enzymes are increasingly used as a new route to synthesize food ingredients such as flavours, emulsifiers, sweeteners, food additives, nutrients. With the advent of genetic engineering, a wide range of enzymes has become available on a large scale and this has increased the scope of enzyme technology.

MICROBIAL ENZYMES: Enzymes are proteinaceous complex organic catalysts of biological origin and vital constituents of cells. Microbes produce a variety of enzymes, intracellular and extracellular enzymes. Most of the microbial enzymes produced for commercial usage are extra cellular enzymes. Extracellular enzymes are secreted outside the cell and hydrolyze polymeric substances. Amylases and proteases are enzymes of economic importance. At present over 60 enzymes are in commercial use, of which three-quarters are hydrolytic enzymes. Commercial production of microbial enzymes utilizes a variety of fungi, yeasts and bacteria. The composition of the medium, genetic stability of the microbial strain and physical and chemical factors of fermentation influence the production of a particular enzyme.

Enzymes catalyze a variety of reactions during processing and preservation of food products and form a large group of processing aids. Food industry utilizes enzymes in the production of bakery items, dairy products, fruits and vegetables juices and products, tenderization of meat, modification of oils and fats, flavour production and preservation of food products. Enzymes have also found use in the manufacture of ingredients like glucose, high fructose syrup, citric acid, colour and flavour constituents.

SINGLE CELL PROTEIN (SCP) AND PROTEIN DEFICIENCY

Protein is an essential component of diet. The greatest single problem in the world today is global food protein shortage. Having adequate quantity of food is only one side of the picture, but the most important aspect is the supply of balanced and nutritious food. All efforts are being made to increase the food production through modern methods of farming. But very little attention is being paid towards protein requirements and production. Approximately half of world population suffers from the protein deficiency disease called ‘Kwashiorkor’ and children with poor protein are victims of this disease.

Usually, cereals have low protein values while protein rich pulses are not available in desired quantities due to poor yields and high costs. The good quality protein available in fish, meat, poultry, and eggs is not available due to poor economic condition as well as varied dietary habits. With the current system of production, agriculture cannot be relied upon to feed an ever increasing world population. Hence there is an urgent need to find other protein sources. The best potential is seen in microbial protein or single cell protein (SCP), a new source of protein independent of agriculture.

DEFINITION: The dried cells of microorganisms such as bacteria, fungi, yeasts, algae that are grown in large scale culture systems as proteins for human or animal consumption are collectively known as "single cell proteins".

Introduction

Hippocrate, an ancient physician, a great thinker and also often referred as father of medicine, for the first time conceive the idea nearly 2,500 years ago that a disease is caused due to natural factors such as environmental factors, diet, and living habits. He advocated the secret of healthy living in healthy food in his famous quote “Let food be thy medicine and medicine be thy food”. But unfortunately, this wisdom about food has faded with the time and we became dependent on synthetic medicines and drugs for even life style disorders. In the last century, research advancement in the field of food science and nutrition established food not only as a source of nutrition but also a source of active food components that aid specific functions and rejuvenated the Hippocrates concept. According to the Department of Health and Human Services, USA, daily diet of a person, plays a crucial role in 5 of 10 diseases which are the leading causes of death, such as diabetes (noninsulin dependent or type 2), stroke, coronary heart disease (CHD), specific type of cancer, and atherosclerosis. In the mid-1980s, term “functional food” was introduce in Japan and defined as food that contain active components either from plant or animal origin and provide physiological benefits in addition to the basic nutritional needs.

1. INTRODUCTION

Flavour is a distinctive property of a substance affecting the gustatory sense. It may be defined as “The sum of those characteristics of any material taken in the mouth, perceived principally by the senses of taste and smell, and interpreted by the brain.” Flavour perception is a complex process which requires the particles to be mixed with saliva and salivary enzymes to promote the release of flavour. Flavour molecules are very diverse in nature. More than 5000 compounds in food have been identified as flavour components which can be detected at very low concentration and are thus, used in products at very low levels. Hexenols and hexenals, characteristic of green taste of fresh fruits and vegetables, can be perceived at a concentration of about 1 part per million (ppm). Naturally occuring flavour compounds are present at a very low concentration ranging from parts per trillions (ppt) to parts per millions (ppm) level. Majority of these compounds are volatile, with boiling points in the range of 20-300 °C. Most of these compounds are lipophilic and possess a great diversity of chemical group and structure with molecular weight ranging between 50-250 g/mol.

Flavour and fragrance compounds are a part of expanding industry with an estimated cost of nearly $27 billion. These comprise of diverse molecules with unique structures and functional groups that contribute to varied aroma and flavour, ranging from floral to fruity notes. The processing operations modify the equilibrium between the different components in raw food that might weaken the original flavour, which require subsequent supplementation. These flavour supplements can be natural or chemically synthesized. Of all the available flavour compounds, around 80% are produced by chemical synthesis whose use is limited due to formation of racemic mixtures and lack of substrate specificity. The growing awareness of consumers towards chemicals supplemented to food has led to the development of the flavouring compounds of biological origin referred to as natural flavours or bioflavours. The first major source of flavour compounds was primarily from plants. Identification of microbes producing vital food flavourants paved the way for alternative low cost, efficient and flexible method for the commercial production of flavour compounds.

The planet earth harbors a total population of 7,530,687,482 (as on 7^th September 2017 at 1345hrs) in which Asia and Africa share 4,486,207,286 and 1,252,251,830, respectively. In majority of the countries in Asia and Africa surveillance programs for detection and source tracking of human health hazard bacteria in foods is scant and in some cases do not exist. Hence, the task is much more complicated especially catering to needs of food, nutritional security and microbial safety of foods of more than 5,738,459,116 or 76.2 % of the total population of the world. The continued occurrence of foodborne illness is not evidence of the failure of our food safety system. In fact, many of our prevention and control efforts have been and continue to be highly effective. In advanced countries like US where food supply is one of the safest in the world, however, significant food borne illness continues do occur. Despite great strides in the area of microbiological food safety, much remains to be done.

Food-borne disease outbreaks are defined as the occurrence of 2 or more cases of a similar illness resulting from ingestion of a common food or observed number of cases of a particular disease exceeds the expected number. These can be confirmed (when at least one causal agent is identified) or suspected (based on clinical and epidemiological information). Although most cases are sporadic, these diseases draw attention to themselves due to outbreaks, thorough investigation of which can help in identifying control measures.Annual burden of foodborne diseases in the WHO South- East Asia Region includes more than: 150 million illness, 175 000 deaths, 12 million DALYs (Source: FERG Report 2010).

4.1 Introduction
At the moment of secretion in the udder, milk is sterile; however, it is contaminated by bacteria before it is extracted from the udder. With the exception of mastitis, the bacteria are generally innocuous and restricted at this juncture. Microorganisms may contaminate the milk further during milking, handling, storage, and other pre-processing activities. The bacteria have the potential to either enhance the quality of milk or cause it to deteriorate. Some of the beneficial bacteria, particularly the lactic acid bacteria, are referred to as probiotics. These probiotics are gaining a more prominent position in nutraceutical dairy and other food products, which provide consumers with health benefits such as the control of diarrhoea, antihypertensive, hypocholesterolemia, immunostimulatory, and anticarcinogenic properties.

4.2 Lactic acid bacteria
This particular group of bacteria is capable of homofermentation, which is the process of fermenting lactose to lactic acid, and heterofermentation, which is the process of generating a high number of end products. They are commonly present in milk and are also used as starter cultures in the production of cultured dairy products, such as yoghurt.

Introduction

Numerous characteristics of food determine its acceptability to consumers and to regulatory officials. Before accepting a food for consumption, it must be attractively presented, must have desirable odour and flavour characteristics and other qualities and must be free from potential pathogens or their toxic products. The ultimate nutritive qualities, flavour and appearance have been preserved and no harmful organisms or substances are present to affect the consumer adversely. If the quality of the product is good, its keeping quality is also likely to be substantial. Conversely, there are more chances of spoilage of an inferior quality food product during storage.

1. Introduction

Fruits and vegetables have been an integral part of man’s diet from immemorial times. Fruits are the portions of plants that bear seeds, while vegetables are the edible components of a plant, including the leaves, stalks, roots, tubers, bulbs, flowers and seeds. These can be eaten raw or cooked. Fruits and vegetables can be preserved for short-term intervals under refrigeration, with or without receiving a minimal treatment like slicing, chopping, shredding or peeling. Fresh produce may also be irradiated or packaged in controlled or modified atmosphere in films for short-term storage. Long-term preservation includes canning, juicing, drying and addition of preservatives. Food contamination with hazardous biological agents remains a worldwide challenge in food safety and nutrition (Kenny 2002; Schlundt 2002; Tauxe et al 1997). Microorganisms form part of the epiphytic flora of fruits and vegetables and many will be present at the time of consumption. Production practices, growth conditions and the location of the edible part during growth (soil, soil surface, aerial part) will in combination with intrinsic, extrinsic, harvesting and processing factors affect their microbial status at the time of consumption. Man-made sources may be directly from farm laborers and from the equipment used for harvesting or storage. The types of microorganisms on fruits and vegetables would also vary with the orchards, vineyards or growing fields. The resident microflora normally subsists on the slight traces of carbohydrates, proteins and inorganic salts that dissolve in the water exuding from or condensing on the epidermis of the host. The numbers of bacteria present will vary depending on seasonal and climatic variation and may range from 104 to 108 per gram. The inner tissues of fruits and vegetables are usually regarded as sterile (Lund 1992). However bacteria can be present in low numbers in the insides of the fruits and vegetables as a result of the uptake of water through certain irrigation or washing procedures.

In the last decade or so, the problem of determining the microbial content and their activities in dairy products has been under close scrutiny. The dairy industries still adopt the dye reduction test because it is cheap, simple and satisfactory. However, other new techniques have been introduced along with some modifications in traditional tests. The microbiological quality must be maintained. To assess the bacterial content and their activities in dairy products, various methods are available for the microbiological testing of milk. The specific tests should be chosen as per the application and other factors like cost etc. On the basis of public health and economic consideration it is necessary to test microbiological quality of milk at a number of points along the chain from producer to consumer which includes - raw milk supply, bulk milk arriving at processors premises, monitoring bulk milk during storage prior to processing and monitoring the procession & the quality control of finished products. The techniques for estimating bacterial numbers in raw material are divided into two categories.

This chapter introduces the microbiological characteristics of eggs and egg products, beginning with the egg's natural physical and chemical defenses against microorganisms. It examines routes of contamination, spoilage microorganisms and spoilage patterns, with particular emphasis on Salmonella Enteritidis and its public-health significance. Other pathogens of concern and the distinctive microbiology of processed egg products are also considered. The chapter discusses microbiological testing, indicator organisms, contamination control and predictive microbiology, providing a foundation for designing effective safety systems throughout the egg value chain.

Microorganism is a collective term for all living organisms, which are not visible to the eye, and occupy an intermediate position between the vegetable and animal kingdoms. They are found every where in the atmosphere, in water and in the soil and, as they break down organic materials, they play a very important role in the cycle of the nature.

There are thousands of species which are important to the life and economic structure of the human race. For example, certain species form simple chemical elements during the break down of dead organic material which plants can use again. They increase soil fertility and crop production which results in more food.

Other species are present, and essential, in animal intestines, helping in the digestion of food.

Some microorganisms are used in many food processes, e.g. dahi, yoghurt, cheese, pickles, beer and wine as well as in the acid production to preserve foods. There are microorganisms that produce toxic substances which kill other organisms, e.g. the mould penicillium which produces the substance penicillin.

Many microorganisms cause diseases in animals and plants with a subsequent reduction in the nation’s food supply, whereas others cause food deterioration such as mouldy foods, tainted foods, etc.

A. Enumeration of Different Microflora of Soil
Introduction
Agriculturally, soil is the region which supports the plant life by providing mechanical support and nutrients required for growth. From the microbiologist view point, soil is one of the most dynamic sites of biological interactions in the nature. Soil is an admixture of five major components viz. organic matter, mineral matter, soil-air, soil water and soil microorganisms/living organisms. The amount/ proposition of these components varies with locality and climate.

The soil organisms are broadly classified in two group’s viz. soil flora and soil fauna, the detailed classification of which is as follows.
1) Soil flora
a) Microflora Bacteria, Fungi, Molds, Yeast, Mushroom, Actinomycetes, Streptomyces, Algae e.g. BGA, Yellow Green algae, Golden brown algae.
b) Macroflora

Micronutrient deficiency

Micronutrient deficiencies are the cause for widespread health problems, especially in developing countries. The deficiencies in vitamin A, iron, and iodine have been identified as the greatest concern, as they affect over one third of the world’s population (WHO, 1995). In addition, these micronutrients interact with each other, i.e., synergistic effects between iodine deficiency disorder (IDD) and iron deficiency anemia (IDA), or between vitamin A deficiency (VAD) and IDA to deepen their negative impacts (Lonnerdal, 2004; Lynch, 1997; Zimmermann et al., 2004). Deficiencies typically coexist in children in developing countries (Zimmermann et al., 2000).

70% of people in India do not consume enough micronutrients such as vitamins and minerals. About 70% of pre-school children suffer from anaemia caused by iron deficiency and 57% of preschool children have sub–clinical Vitamin A deficiency. Neural Tube Defects (NTDs) are the most common congenital malformation with an incidence that varies between 0.5-8/1000 births. It is estimated that 50-70% of these birth defects are preventable. One of the major causes is deficiency of folic acid. Thus, micronutrient deficiency also known as “hidden hunger”, is a serious health risk. Unfortunately, those who are economically disadvantaged do not have access to safe and nutritious food. Others either do not consume a balanced diet or lack variety in the diet because of which they do not get adequate micronutrients. Often, there is considerable loss of nutrients during the processing of food.

Introduction The Indian culinary world may have just recently embraced the concept of edible flowers, but they have been a part of traditional Indian cuisines since the beginning. Flowers have been used in human diets and gourmet preparations for thousands of years (Fernandes et al., 2020). However, due to increased consumer knowledge about the effects of nutrition on human health, there is a growing trend in utilizing flowers for edible purposes (Chatzopoulou et al., 2020). Edible flowers were used as a relish and flavour enhancer in many savoury and sweet meals in ancient Rome and Greece. In China’s ancient texts and classics, the words and phrases regarding edible blossoms were also recorded by Zhao et al. (2017). Edible flowers come in a wide variety of colors and cooking ways in different nations. Flowers, such as Osmanthus fragrans Lour and Flos Sophorae, have been employed as basic ingredients in a range of Chinese cuisines (Cunningham, 2015). The people of Rome used flowers in cooking. They make salads using violets and roses and sauces using lavenders. Flowers from pumpkin and squash plants have long been used as ingredients in the United States. People consume aromatic flower buds and unopened blossoms in El Salvador and Honduras. Blossoms are frequently used to garnish food at aristocratic banquets and feasts across Europe. Dandelion (Taraxacum officinale) flowers are also added to beverages and salads in many parts of the world.

Introduction

Encapsulation may be defined as a process to entrap one substance (active agent) within another substance (wall material). The encapsulated substance, except active agent, can be called the core, fill, active, internal or payload phase. The substance that is encapsulating is often called the coating, membrane, shell, capsule, carrier material, external phase, or matrix. In the food industry, encapsulation process can be applied for a variety of reasons. Encapsulation is a useful tool to improve delivery of bioactive molecules (e.g. antioxidants, minerals, vitamins, phytosterols, lutein, fatty acids, lycopene) and living cells  (e.g. probiotics) into foods [1]. In most cases, encapsulation refers to a technology in which the bioactive components are completely enveloped, covered and protected by a physical barrier, without any protrusion of the bioactive components. Also, encapsulation has been defined as a technology of packaging solids, liquids, or gaseous materials in small capsules that release their contents at controlled rates over prolonged periods and under specific conditions. Produced particles usually have diameters of a few nm to a few mm.

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.

Abstract

Micronutrient (vitamin and mineral) deficiencies affect more than 2 billion people worldwide and are especially prevalent in developing countries including India. Conditions due to vitamin mineral deficiencies account for 7.3 percent of the global disease burden.Iron deficiency (anemia), vitamin A and iodine deficiency disorders continue to be a grim public health problem. Thus, elimination of vitamin and mineral deficiencies is essential to improve the overall health of the masses as well as to sustain economic growth and national development. Food fortification is an effective intervention to deliver vitamin and mineral rich foods to large populations. In addition to the prevention of vitamin and mineral deficiencies, food fortification is an effective measure to raise vitamin and mineral levels by moving the population towards consuming recommended dietary allowances for most micronutrients-making it a long–term and a sustainable strategy. India is the largest producer of milk in the world with 146.3 million tonnes and the consumption rate of milk and milk products by all age groups of people are high.Therefore, fortification of milk with mineral and vitamins could be a safe and effective strategy to fight these micronutrient deficiencies.

1.    Yoghurt usually contains total milk solids in the range of

(a) 12-15%

(b) 8.5 to 11.5%

(c) 15-19%

(d) 20-25 %

2.    Yoghurt is usually manufactured by heating the pre-mix to pasteurize it to

(a) 61-62°C for 20 minutes

(b) 80-85°C for 15 to 30 minutes

(c) 80-85°C for 15 sec

(d) 71-72°C for 15 sec

One of the major discoveries that gave birth to the field of microbiology was the development of instruments that could magnify, so that objects too small to be seen with the naked eye could be visualized. Robert Hooke in 1665, using an instrument with two sets of lenses (a crude compound microscope), was the first person to describe cells as life’s smallest structural units. In the early 1670s Anton van Leeuwenhoek used a simple magnifying lens to observe microbes he called ‘animalcules’ in rainwater, and was possibly the first person to observe microorganisms. The development of electron microscopes in the 1930s enabled magnifications of a further hundred times greater to be achieved.

A microscope can be defined as an optical instrument consisting of a lens or a combination of lenses for getting magnified images of minute objects. A simple microscope is essentially an ordinary magnifying lens held on an adjustable stand. It can give magnification up to 20 times the size of the object.

Abstract

In recent years microwave processing have attained increasing recognition in food industries particularly in drying and dehydration. During microwave processing, electromagnetic energy is supplied directly to the food material for volumetric heating. This provides rapid temperature rise throughout the material with reduced thermal gradients. This unique heating mechanism reduces processing time and saves energy. In-spite of advantages of microwave heating it leads to overheating in food material and formation of cold and hot spots if applied improperly during drying. To overcome these challenges different microwave assisted hybrid drying technologies have been developed by many researchers. These techniques are microwave assisted hot air drying, microwave assisted osmotic dehydration, microwave assisted vacuum drying, microwave- infrared assisted hot air drying, microwave assisted rotary drying. This chapter comprises the fundamentals of microwave and provides comprehensive update of microwave assisted hybrid drying processes for food and agricultural materials.

1. Introduction

Thermal processing used extensively in the food industry for preservation and shelf life extension of the products (Arnoldi 2001). Heat treatments remain most important in food processing unit operations, not only to achieve desirable changes in eating quality but also for preservative effect by inactivation of microorganisms, destruction of enzymes and insects.Heat is applied in various unit operations through adifferent mode of heat transfer such as conduction, convection, and radiations. 

Abstract

Hot air circulation is the most common industrial method of drying foods which has its own inherited disadvantages. Microwave drying can be an alternative method for removing moisture from foods and there has been a surge of interest in the application of microwave to process the foods, in past few years. The reason being that there is worldwide energy crisis and the growing acceptance and familiarity with domestic microwave ovens. It is well known that conventional means of heat processing irreversibly alter the flavor, colour, and texture of many foods. From the point of flavor alone, it is desirable to improve our present methods of processing foods. Some improvements have been made in this direction with a number of food products by use of high-temperature short- time processing.

Food adulteration is a global issue, and because there are insufficient regulations and oversight, developing nations are more vulnerable to it. But in many nations, food adulteration has gone unnoticed. Contrary to popular assumption, milk adulterants can, regrettably, present major health risks that result in fatal diseases. Modern milk adulteration involves increasingly complex techniques, necessitating state- of- the- art research to identify the adulterants. Because milk contains so many nutrients that are needed by both adults and infants, it is referred to as the ideal food. In terms of protein, fat, carbohydrates, vitamins, and minerals, it is among the best sources. Regretfully, milk adulteration is a very common problem worldwide. Potential causes could be the gap between supply and demand, the perishable nature of milk, the low purchasing power of the consumer, and the absence of appropriate detection tests. Because there is insufficient oversight and inadequate law enforcement, the situation is substantially worse in developing and underdeveloped nations. While quantitative detections of adulterants in milk are varied and complex, qualitative detections can be carried out simply using chemical reactions. The type of quantitative detection methods used depends on the milk’s adulterants.

Typical Adulterants in Milk

The addition of vegetable protein, milk from different species, whey addition, and watering are the main adulterants in milk that are known to be economically motivated. There is no serious health risk associated with these adulterations. Some adulterants, though, are too dangerous to ignore. Urea, formalin, detergents, ammonium sulfate, boric acid, caustic soda, benzoic acid, salicylic acid, hydrogen peroxide, sugars, and melamine are a few of the main adulterants in milk that have been shown to have serious negative health effects.

5.1 Introduction

Waste from the dairy processing industry is generated through production of milk products at different stages. With diversification of dairy products, by-products have also gained some importance. Utilization of dairy by- products improves economical and nutritional aspects of milk production and reduces environmental pollution originating from dairy waste. Important dairy by-products include butter milk, ghee residues and whey, the major waste arising from production of cheese, casein, paneer and chhana. Whey arises as a result of protein coagulation/precipitation in the preparation of these products. It is used for manufacture of whey powder, whey drinks and lactose (milk sugar). Whey protein concentrates can be prepared by modern technological methods like ultra-filtration and reverse osmosis. Desi buttermilk is an important domestic beverage since olden days. Ghee residue can be utilized for manufacture of chocolate burfi, samosa filling etc. Hence, utilization of dairy waste particularly whey, butter milk and ghee residues obtained during manufacturing of various main products, has not only increased the availability of nutritional milk foods but has also indicated the profitable method of by products utilization and helped in minimizing the problems of pollution. This chapter focuses on utilization of these dairy industry wastes.

    1.    As per FSSAI, 2011 regulations, what is the fat and SNF content in buffalo milk
        a)    5 & 9    b)    6 & 8
        c)    6 & 9    d)    None
    2.    As per FSSAI, 2011 regulations, what is the fat and SNF content in  cow milk
        a)    4 & 9    b)    4 & 8.5
        c)    6 & 9    d)    None
    3.    As per FSSAI, 2011 regulations, what is the fat and SNF content in  standardized milk
        a)    4 & 9    b)    4.5 & 8.5
        c)    6 & 9    d)    None

Importance

The dairy products, which have originated in India, are called indigenous dairy products. The products can be broadly classified in to khoa based and channa based. The importance of the dairy products were known to Indians since time immemorial or it could be roughly estimated to be around five thousand years ago and the development could be considered as an art.

Introduction

There has been a considerable progress in the overall production in the dairy sector. Without a proper marketing, the country would not attain the expected rate of growth in dairy farming. Marketing is a flow of goods and services from producer to consumer and users. In this process the activities include moving the goods from the point of production to the point of consumption. The activities like creation of time, place, form and utility are involved. According to Philip Kotler, marketing as a human activity directed at satisfying the needs and wants through exchange process. The performance of the trade activities involved in the f low of goods and services affect the marketing efficiency and producers share in the consumer rupee. A marketing system consists of different milk marketing channels. That marketing channel is considered good in which producer get the highest share in consumer rupee and consumer share is highest in producers rupee. The interest of the Producer is to get the highest possible returns from their milk. Between them, there are marketing intermediaries or middlemen who perform various marketing functions like transporting and retailing. All the intermediaries/ middlemen are also interested to make highest profit from the milk business. The present lesson provides information on the economic aspect of marketing of milk and milk products through a empirical study conducted in Rajasthan state.

1. Ethyl alcohol content in alcoholic beverages is determined by Pyknometer Method or SG (Hydrometer) Method (after distillation). %Alcohol (v/v) = 8610.6 – (16584 x SG) + (7973.3 x SG 2)
2. 1 ml of 0.05N NaOH is equivalent to 0.00375 g of tartaric acid.
3. Volatile acidity of alcohol drinks is measured in terms of as acetic acid. 1 ml. of 0.05N NaOH is equivalent to 0.003g of acetic acid.
4. Esters in alcohol drinks is expressed as ethyl acetate gms. per 100 liters of abs. alcohol. 1 ml. of 0.1N NaOH is equivalent to 0.0088g of Ethyl acetate.
5. Esters in Higher alcohol drinks is expressed as Amyl alcohol gms. per 100 liters of abs. alcohol.1 ml of 0.1N NaOH is equivalent to 0.0088g of Amyl alcohol.
6. The concentration of Higher alcohol g/100L is determined by spectrophotometer method using p-dimethylaminobenzaldehyde solution by reading the % T or Absorbance (OD) of developed colour of samples and series of standards in spectrophotometer at 530/535 nm against reagent blank as reference.

The significance of milk in human nutrition is now well established as it is considered as the best, ideal and complete food for all age groups. However, in spite of being so, milk can also serve as a potential vehicle for transmission of some diseases under certain circumstances. Moreover, by virtue of possessing almost all the essential nutritional factors, milk can also serve as an excellent culture and protective medium for certain microorganisms, which may include potential pathogens capable of causing serious health problems to the consumers. In this way, milk may serve not only as a vehicle of transmission of disease causing organisms, but it can also allow these pathogens to grow, multiply and produce certain toxic metabolites, thereby making itself an extremely vulnerable commodity from public health point of view.