eChapters

Introduction

Spray drying process has been used for decades to encapsulate food ingredients such as flavors, lipids, and carotenoids. During this drying process, the evaporation of solvent, that is most often water, is rapid and the entrapment of the interest compound occurs quasi-instantaneously. This required property imposes a strict screening of the encapsulating materials to be used in addition to an optimization of the operating conditions. Likewise, if the encapsulated compound is of hydrophobic nature, the stability of the feed emulsion before drying should also be considered.

Stabilizers and emulsifiers are used in small quantities but have major effects on the structure and quality of ice cream. This chapter explains the differences between these two functional ingredient groups and describes their roles in controlling water mobility, fat destabilization, air-cell stability, texture, meltdown, and heat-shock resistance. It discusses commonly used stabilizers and emulsifiers, their individual characteristics, and the advantages of using blended systems. Particular attention is given to formulation balance and the defects that may arise from incorrect selection or dosage, including gummy texture, weak body, poor meltdown, and structural instability. Practical guidelines help manufacturers select and use these ingredients effectively for consistent product quality.

Abstract

The aim of this work was to reduce the natural fermentation period of ‘idli’ from the conventional 14 hr to10 hr by adding underutilized okara for the preparation of ‘idli’. Black gram was partially substituted with soy residue okara in the ratio of (1:1). After 14 hr of natural fermentation, the pH and total acidity of control ‘idli’ batter was 4.55 and 0.68% and that of okara fortified ‘idli’ batter was 4.57 and 0.56%, respectively. The amount of CO₂ released by the control and okara fortified batter was 12.5% and 22.5% respectively. The viable count of yeast and mold, lactics and mesophilic bacteria in control and okara batter increased with time reaching 8.4 and 9.6, 8.2 and 7.5, and 8.6 and 9.2 log10 cfu/g, respectively at the end of 10 hr of natural fermentation. Okara fortified ‘idli’ was soft and spongy compared to control ‘idli’.

8.1 Introduction
The chemical composition of milk intended for market or milk product manufacturing must be standardised in numerous dairy processes. Standardising milk may necessitate the regulation of a single component (typically fat) while permitting the other components to shift or regulate two or more components concurrently. Definition: The term “standardisation” of milk denotes the process of adjusting the fat and solids-not-fat percentages of milk to the desired value in order to comply with the legal or other requirements.
Objectives of standardization are
1. To ensure that specific milk and dairy products meet legal requirements.
2. To offer a consistent product to the consumer.
3. To guarantee economic efficiency in production.
The volume of milk available for sale is increased by the addition of skim milk, and the separation of cream enables the production of other value-added dairy products, such as butter, table cream, or other high-fat products.

The stiffness of starch gels from different starches at 5% concentration was shown in decreasing order of stiffness in the following table. Of the cereal starches corn starch gel was firmest followed by wheat and rice starch gels. Among the roots and tubers starches, potato yielded a ropy paste, arrowroot a soft paste while cassava starch gave viscous fluid.

Starters are selected strains of micro-organisms deliberately added to milk during conversion into cheese, dahi, yoghurt and other fermented dairy products to bring about specific changes in the appearance, body, texture and flavour characteristics of the desired final products.

Functions of Starters

The primary function of almost all starter culture is to develop acid in the product. The secondary effects of acid production include coagulation, expulsion of moisture, texture formation and initiation of flavour production. In addition to these, the starters also help in imparting pleasant acid taste, conferring protection against potential pathogens and providing a longer shelf life to the product. These bacteria convert 1% of lactose in milk approximately to lactic acid with very little by-products such as acetic acid, ethanol, CO2 and normally with no substances causing taints and hence leading to a clean and wholesome milk souring.

Starter cultures were unknown until 1878, when Lister isolated pure cultures of the lactic acid bacteria responsible for milk acidification. In the 1980s, improvements to standardization and ripening of butter were made by introducing pure starter cultures. During the period 1910-20, Orla-Jensen, von Freudenreich, Sherman, Hammer and other dairy microbiologists prepared pure cultures for fermented milks. Commercial production and use of starter cultures grew rapidly and was widespread at the beginning of the 20^th century.

Dairy starters are the ‘heart’ of fermented milk products, the most crucial component in the manufacture of high-quality fermented milks. The cultures are harmless food-grade microorganisms, active bacteria intentionally grown in milk or whey or other formulated media which impart desirable and predictable flavour and texture to fermented dairy products.

The dairy microorganisms employed in milk fermentation are single-strain or multiple-strain cultures of lactic acid bacteria, producing different types of fermented milk products. Usually, one or two strains dominate the milk environment. Individual strains can be selected in advance for their resistance to both bacteriophages and antibiotics. Mixed starter cultures are used to ensure that fermentation will continue after a bacteriophage attack. Bacteriophages are highly strain-specific, and if the dominant strain in a mixed-strain starter culture succumbs to an attack, the phage-resistant mutant or the next dominant culture maintains a satisfactory rate of lactic acid production.

Abstract

Agro-food industries generate a large amount of by-products and wastes. These byproducts and wastes have a negative impact in terms of the environmental concern due to the increase of pollutant disposal, and industrial sustainability because of high costs related to their management. These byproducts and wastes are rich in minerals, sugars and proteins. The composition and characteristics of wastes from different food processing industries vary and rely upon the production technique and the nature of the product. India is the second largest producer of rice/paddy in the world and the utilization of rice bran is gaining importance. However, a small fraction of these have been utilized. In case of fruits and vegetables, industrial processing of potato generates between 70 and 140 thousand tons of peels worldwide annually. Moreover, 37% of world’s total annual production of banana is shared by India. Hence, to minimize the disposal fees and trash collection new policies and methods have been developed for handling and treatment of wastes and byproducts. This chapter envisages the status of different agro-food industrial byproducts and wastes for the development of different food and non-food products.

Introduction
Sterilization of culture media, containers, and instruments is crucial in bacteriological work to ensure the isolation and maintenance of pure cultures. Sterilization and sanitization are essential processes in a microbiology lab to prevent contamination and ensure accurate results. Sterilization refers to the complete elimination of all microorganisms, including bacteria, fungi, viruses, and spores, using methods like autoclaving, dry heat, filtration, and chemical agents. Sanitization, on the other hand, reduces microbial load to a safe level through cleaning and disinfection using alcohols, detergents, and UV light. These practices maintain aseptic conditions, protect lab personnel, and preserve sample integrity. Proper sterilization and sanitization are fundamental to microbiological research, clinical diagnostics, and industrial applications, ensuring reliable and reproducible experimental outcomes.
Preparations for Sterilization Before sterilization, cleaned and dried test tubes and flasks should be carefully plugged with clean, non-absorbent cotton. Pipettes should also be plugged at
the mouth end, and the plugs should remain in place during use to minimize oral contamination. Cotton plugs provide sufficient ventilation for bacterial growth while preventing external contamination.

Sterilization is defined as the process by which an article, surface or medium is freed of all living microorganisms either in the vegetative or spore state.

Disinfection means the destruction or removal of all pathogenic organisms, or organisms capable of giving rise to infection. Chemical disinfectants which can be safely applied to skin or mucous membrane and are used to prevent infection by inhibiting the growth of bacteria are called antiseptics.

Five main methods are used for sterilization. 1. Red heat (flaming) 2. Dry heat (hot air) 3. Moist heat 4. Filtration 5. Radiation.

The killing effect of dry heat is due to protein denaturation, oxidative damage and toxic effect of elevated levels of electrolytes. The lethal effect of moist heat is due to the denaturation and coagulation of protein. In the case of spore, steam condenses on it, increasing its water content with ultimate hydrolysis and breakdown of the bacterial protein.

Sterilization is a thermal process aimed at destroying all microorganisms and microbial spores in milk, ensuring the product is microbiologically safe and shelf-stable at room temperature for extended periods. It is primarily used in the production of sterilized milk and evaporated milk, with typical conditions involving heating at 116°C for 15 minutes. This process kills all microorganisms and also inactivates all milk enzymes, including plasmin, which might otherwise contribute to spoilage during storage. However, enzymes produced by psychrotrophic bacteria should not be present in raw milk, as they are highly heat-stable and may remain active even after sterilization. Sterilized milk can be stored at room temperature for longer period. Sterilization kills all microorganisms and inactivates all microbial spores that may germinate under the storage conditions of the product in the market.
The Food Safety and Standards Authority of India (FSSAI) define “sterilization” in relation to milk and milk products as the process of heating the product in a sealed container continuously to at least 115°C for 15 minutes. This treatment ensures that the milk can be preserved at room temperature for a period of not less than 30 days.
In-bottle sterilised milk is a shelf-stable dairy product produced by sealing milk in glass bottles and subjecting it to high-temperature heat treatment. Typically, the milk is heated to temperatures ranging from 110°C to 121°C for 15 to 30 minutes. This process effectively destroys all vegetative microorganisms and bacterial spores, making the milk microbiologically safe and extending its shelf life up to 6–9 months without refrigeration. The heating is usually done in batch retorts or autoclaves after the milk has been bottled and sealed. Although the process ensures safety, it often leads to a slight cooked flavour and some nutritional losses, particularly in heat-sensitive vitamins such as vitamin B1 and vitamin C.

Introduction

Enterprise management involves a combination of tools, strategies, and processes that work together to form a cohesive plan and framework supporting overall operations. The key is ensuring that these elements are interconnected, which enables the smooth flow of information and minimizes redundancies.

Core business functions such as human resources and supply chain management often operate in isolation. However, this separation can slow down business operations, create unnecessary obstacles, and lead to loss of revenue or customers.

By viewing each business area as interconnected, these silos can be eliminated, leading to more efficient operations. For instance, a well-functioning human resources team can hire the right talent, which, in turn, strengthens marketing and sales efforts. As sales grow, revenue increases, enabling further improvements in logistics operations.

Street Foods-An Introduction

The National Policy on Urban Street Vendors (2004) defines street vendor as a person who offers goods for sale to the public without having a permanent built-up structure but with a temporary static structure or mobile stall (or head load). Street vendors may be stationary occupying space on the pavements or other public/private areas, or may be mobile in the sense that they move from place to place carrying their wares on push carts or cycles or baskets on their heads, or may sell their wares in moving trains and buses. The total number of street vendors in India has been estimated to be ten million and the number of street food vendors has increased sharply in the past few years (Bhowmik 2005).

The preparation and sale of street food is an age-old activity with historical roots and complex socio-economic and cultural implications. Street food vendors are mostly outside the regulation of the governments and unregistered thus making them an informal sector. Similar to most other informal sector enterprises street food operations too are carried out with minimal investment, infrastructure and as familial operations. Street food outlets are seen mushrooming at crowded public places like bus stands, cinema halls, market areas and parks. They operate as temporary structures or as pushcarts parked near the roadside or at pavements. Most street food vendors operate their food stands alone and are able to generate sufficient income for sustenance.

Size shape and Appearance of Bacterial cells

Bacteria vary significantly in their morphology, that is in their appearance. They range in size from 0.2 μm to1 μm in diameter and 1 μm to 10 μm in length. There are three basic shapes of cells :

1. Spherical

2. Rod-shaped

3. Spiral.

Abstract

This review presents an idea on the botanical description, medicinal properties and traditional usage of wild, edible and aromatic plant (Nymphaea alba) in the human nutrition. Nymphaea alba Lin, also known as the White Water lily, White Lotus, or Nenuphar is an aquatic flowering plant of the family Nymphaeaceae. Nymphaea is a weed in India and its production pretty much as good as water chest nut and Nelumbo nucifera. Its rhizome is rich in tannic acid, gallic acid, alkaloids, sterols, flavonoids, glycosides, hydrolysable tannins and high-molecular-weight polyphenolic compounds. It is used as associate aphrodisiac, anodyne, antiscrophulatic, astringent, cardiotonic, demulcent, sedative and antiinflammatory. Further, it conjointly produces calming and sedative effects upon the nervous system, and is beneficial within the treatment of sleep disorder, anxiety and similar disorders. Moreover, the content of starch in the rhizome is said to be 40%. Extensive work has been carried out on agronomic and phenotypic properties for most plants, but relatively little study has been carried out on the properties which are of direct technical and economic interest to competitive food and nonfood industry. Non-conventional food resources and their value addition have attracted attention in the recent yearsfor their potential use as functional ingredients in food formulations, besides food they have also been used for non-food applications. Moreover, Plants provide the predominant ingredients of medicines in most medical traditions. So, there is tremendous potential for the profitable industrial use of these medicinal plants and exploring them for further use. Keywords: Non-conventional food resources, Nymphaea alba, Rhizome.

Abstract

In the present study, a novel work on comparison of physico-chemical characterization and bacterial diversity of wheat straw compost and vermicomposting has been initiated in the tropical region. Wheat straw compost shows lesser pH, EC, TDS, Organic Carbon, Total Nitrogen and Total Phosphorus than vermicompost whereas there was an increase in Total Nitrogen, Total Phosphorus and Electrical Conductivity and a drop in the pH, TDS and Organic Carbon of the vermicompost as the composting progressed from 0, 3, 10, 17, 24 and 31 days. Strains of Bacillus spp. and Thermoactinomycetes were screened from the wheat straw compost, which are ecologically important and have commercial potential for enzyme production. These strains were able to degrade cellulose, hemicellulose and lignin and exhibited cellulase activity. Enterobacter aerogenes, Micrococcus luteus and E.coli were isolated from the gut of Eudrilis eugeniae which help in the transformation of biodegradable waste materials into valuable compost.

Abstract

Microencapsulation has found great applications in food business. However, the technology remains aloof from being fully exploited. Microcapsules offer food processors a way to shield sensitive food ingredients, mask or preserve flavours and aromas and conversion of volatile food components into easy-handled solid ingredients (like powders, capsules etc). A number of naturally occurring and synthetic polymeric materials have been identified so far that possess the entrapping property and are categorised as GRAS materials. Numerous techniques have been developed for using these entrapping materials to encapsulate the sensitive food ingredients. Controlled release of the food ingredients at proper place and right time could be therefore a key practicality that may be provided by microencapsulation. With strictly fine-tuned and stabilized release characteristic, this method adds worth to the merchandise. The areas of interest in this field include the development of alternative and inexpensive polymers that may be considered natural or mimic the properties of natural polymeric materials, like Gum Arabic, Gellan Gum, Gum Karaya, Gaur Gum and Gum Acacia. Limitations in many of the encapsulation techniques have occurred due to high value of raw materials and production. This review is effectively committed to the, properties of encapsulating agents along with the emphasis on different techniques used for encapsulation in the varied fields like food technology, pharmaceutical, commercial engineering and biotechnology.

Introduction
Microbiology techniques are used for various objectives like:
• To observe and isolate the micro-flora
• To test the microbiological quality of various food and dairy products
• To find the presence of any particular pathogenic microorganism
• To maintain a pure or mixed culture of specific microorganisms
1. Serial Dilution Techniques
• Bacteria are often present in such huge numbers that they can be difficult to count. Yet accurate counts are necessary for a variety of reasons like, for instance, assessing the quality of water or the safety of food. There are a number of counting techniques but most rely on the dilution of the sample to reduce the bacterial numbers down to a quantity that can be counted accurately.
• All bacterial plate count methods require the sample to be serially diluted until an estimated count of 30-300 colony forming units (CFU) on the plate is obtained. Plates with more than 300 CFU are very difficult to count. Plates with less than 30 CFU are not statistically reliable.
• If turbidity is observed in a broth culture, it might have millions more bacteria than you need. If this turbid broth is used directly for plating, all the CFU would grow together into a confluent mass and we would not be able to distinguish one colony from another.

Introduction
A) Cultivation of Fungi
A fungus is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, Fungi, which is separate from the other eukaryotic life kingdoms of plants and animals. A characteristic that places fungi in a different kingdom from plants, bacteria, and some protests is chitin in their cell walls. Similar to animals, fungi are heterotrophy; they acquire their food by absorbing dissolved molecules, typically by secreting digestive enzymes into their environment. Fungi do not photosynthesize. Growth is their means of mobility, except for spores (a few of which are flagellated), which may travel through the air or water. Fungi are the principal decomposers in ecological systems. These and other differences place fungi in a single group of related organisms, named the Eumycota (true fungi or Eumycetes), which share a common ancestor (form a monophyleticgroup), an interpretation that is also strongly supported by molecular phylogenetics. This fungal group is distinct from the structurally similar myxomycetes (slime molds) and oomycetes (water molds). The discipline of biology devoted to the study of fungi is known as mycology. In the past, mycology was regarded as a branch of botany, although now known fungi are genetically more closely related to animals than to plants.

(A) Effect of Temperature
Introduction
Temperature is one of the most important physical factors affecting microorganisms. Bacteria are different from higher plants and animals in the lack of homeostatic mechanism and cannot regulate heat generated by metabolism and are, therefore, directly and readily affected by temperature. Over a limited temperature range, there is a two-fold increase in the rate of enzyme catalyzed reaction for every 10°C rise in temperature.
Bacteria may be divided into three major groups with respect to their temperature requirements: (i) Psychrophiles, those with optimum temperature between 0°C and 20°C; (ii) Mesophiles, with optimum temperature between 20ºC and 40°C and (iii) Thermophiles, with optimum temperature between 40°C and 80°C. Thermophiles are of two types: (a) Facultative thermophiles with an optimum temperature of growth between 45°C and 60°C and (b) Obligate thermophiles with optimum temperature above 60°C. Temperatures in the range between 50°C and 100°C are normally in the lethal range for bacterial cells and spores. The range of temperature preferred by bacteria is genetically determined, resulting in enzymes with different temperature requirements.
Each organism grows within a particular temperature range (i.e. cardinal temperature points). The minimum growth temperature is the lowest temperature at which growth of a species will occur. The highest temperature at which a species can grow is its maximum growth temperature, and a species grows fastest at its optimum growth temperature.  Time of exposure is a vital factor in assessing the