eChapters

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