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Fruits and vegetables are very important food commodities not only in developing country like India but all over the world. India, which is the most densely populated country in Asia continent, is still struggling to achieve self-sufficiency to feed about 135 crores people. For this purpose, fruits and vegetables have got their specific importance to provide a balance and healthy diet to the Indian people. Therefore, the reduction of post-harvest loss of fruit and vegetables is a complementary means for increasing production. It may not be necessary to considerably step up the production of fruits and vegetables with the growing demand if the post-harvest loss is reduced to a great extent. The cost of preventing losses after harvest in general is less than preventing a similar additional amount of fruit and vegetable crop of the same quality

Fruits are important source of Pro-vitamin A and vitamin C. In addition, vegetables also supply fair amount of carbohydrates, protein and energy and add colour, flavour and aroma to human diet. India is one of the largest producers of fruits and vegetables. Fruits and vegetables are an important supplement to the human balanced diet as they provide the essential minerals, vitamins and dietary fibre (roughage) for maintaining the tear and wear of the over body. Fresh fruit and vegetables have a short shelf life under ambient conditions of temperature and humidity due to their highly perishable nature. They soon lose their freshness and become subjected to mould and bacterial attack, and consequently decay and become useless as articles of human diet. Fresh fruits and vegetables are valued for their quick sources of available energy. Fresh fruits have high water content (70-96%), varying amount of carbohydrate (3-27%) and fibre (0.2-3.1%) and a low content of protein, fat and minerals. Ideal climatic conditions ensure round the year availability of broad range of fruit and vegetables in large quantities. The production of fruits and vegetables was 97.00 MT and 179.60 MT during the 2017-2018 in India

Traditional food-preservation methods reflect generations of practical knowledge concerning food safety, storage and seasonal availability. Although commonly performed at the household level, these methods are supported by scientific principles such as reducing water activity, lowering pH, inactivating enzymes and restricting microbial growth. Blanching, fermentation, sun drying, increasing solute concentration, pickling, smoking and curing preserve foods through different combinations of heat, dehydration, acidity, beneficial microorganisms and antimicrobial compounds. Their materials and equipment are generally accessible, making them suitable for home-scale application. The chapter explains the principle, mechanism, application and nutritional implications of each method while showing their continuing relevance in contemporary food systems.

Dahi: It is the product obtained from pasteurized or boiled milk by souring, natural or by harmless lactic acid or other bacterial culture. It is also called Curd (Plate 126).

Daidzein: These are the substance from which daidzein is derived and are isoflavone C15 H10 O4 found chiefly in legumes and esp. soybeans.

Dairy: It is a farm building often a single room in which milk is cooled and temporarily stored prior to collection for transportation to the commercial diary. Here the milk is treated and made into cream, butter and cheese. Or

Dairy: It is a farm building often a single room, in which the milk collected is pooled, temporarily stored prior to collection for retailing or direct sale to the consumer. OrDairy: It is a room, building, or establishment where milk is kept and butter / cheese is made or it is the department of farming / farm that is concerned with the production of milk, butter, and cheese oran establishment for the sale / and distribution of milk and milk products.

Dairy farm: It is a farm on which the principal activity is the milk production.

Dairy husbandry: It deals with care, breeding, feeding, milking of the diary cattle and the production and sale of the milk. It is the economical management of a dairy, including looking after the dairy cattle and proper disposal of milk and milk products.

Dairy products: These are the milk preparation, including butter, cream, cheese, ghee, yoghurt, pasteurized milk, tonned milk, butter milk etc processed and prepared in dairy. Ice cream and kulfi or sweets are not included in this.

Damage: Damage is a physical spoilage, often a partial deterioration, are subjectively judge and very difficult to measure and usually reported as % of the sample. Daminozide: It is a growth regulator which is used for red colour development in apple.

Electromagnetic and advanced heating technologies offer rapid and energy-efficient alternatives to conventional food processing. These systems use microwaves, radio frequency, electrical resistance, infrared radiation, lasers, photonic energy and dielectric heating to generate heat within food or directly at its surface. Faster and more uniform energy transfer can improve microbial inactivation, shorten processing time and reduce damage to nutrients and sensory characteristics. The chapter explains the principles, mechanisms, applications and nutritional effects of microwave, radio-frequency, ohmic and infrared heating. It also considers laser-based and photonic techniques. Particular attention is given to heating uniformity, product properties, equipment control, energy efficiency and the prevention of underprocessed areas.

1.1 Introduction Millets are the most ancient grains that have been cultivated since time immemorial and consumed as food, feed and pastures. Millets are considered nutraceuticals’ since they possess significantly higher nutritional qualities compared to other cereals. Millets are grown across the world for grains and human food due to their nutritional advantages and ability to withstand adversities. Millets are preferred over other grains due to their short life cycle, low input requirement and ensured production with in-built genetic tolerance for abiotic stresses. Major millets include Pearl millet (Pennisetum glaucum L.) and sorghum (Sorghum bicolor L.), while there are numerous minor millets classified as small millets. With an extent of over 0.87 lakh ha and a production of 0.66 kg ha-1, India is the world leader in small millet production (Maitra and Shankar, 2019). Small millets are primarily grown on rainfed uplands in arid and semi-arid climates with sub-optimal management. Following the green revolution due to extreme demands for food, the main focus in India was on the production of fine cereals mainly rice and wheat to overcome hunger and poverty, while millets became ignored grains. Furthermore, urbanization, increased affluence and dietary changes relegated millets to the status of poor man’s food. However, due to a re-evaluation of nutritious characteristics, millets have recently regained their lost prestige (Maitra, 2020).

Emerging preservation technologies are being developed to meet increasing expectations for food safety, nutritional quality, sustainability and longer shelf life. Greater investigation remains necessary to understand their effects, limitations and suitability for large-scale industrial application. This chapter examines innovative physical, chemical and biological methods used at different stages of the food chain. Technologies include plasma-activated water, cold atmospheric plasma, advanced oxidation, electrolysed water, space-food preservation, hurdle systems and biopreservation. Their mechanisms involve reactive species, microbial membrane damage, oxidation, combined environmental stresses and beneficial biological agents. The chapter assesses their applications, advantages and disadvantages while highlighting research, regulation, process standardisation, equipment cost and commercial scalability.

Fermentation process is known to humans since ancient times. It involves the transformation of raw materials into value added or nutritional products as a result of microbial action or their growth. The fermentation as a science involves aspects of the biological action of microbes, biochemical changes in the substrates and metabolites formed and their effect on food, health and nutritional applications. While fermentation as technology, involves chemical engineering, food engineering and instrumentation aspects and commercialization of the products prepared keeping in view the consumer acceptability. The term fermentation is derived from the Latin word ‘Fervere - to boil’ thus describing the actions of yeasts on extracts of fruits or malted grain. Fermented foods and beverages enhance the pleasure of eating and their nutritional roles include indirect contributions through subjective enhancement of appetite. The instant mixes for fermented or fermentable products such as idli, dosai, dhokla and bhatura mix can reduce the overnight fermenting of the raw materials required for preparation of these products. The instant mixes for idli & dhokla are quite common in the market. However, instant mix for Jalebi and Bhatura are still emerging. Such products add convenience to the consumers and products can be prepared instantly. Certain other fermented foods include dairy products, pickles, sauerkrauts, Kanji, beverages, food supplements and nutraceuticals from fermented biomass.

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.

The fungi are usually:

a) Parasites or saprophytes b) Lithophytes

c) Epiphytes d) Insectivorous

The production of fruit crops is largely dependent on the environmental conditions and nutritional status of the plants. Any alteration in the environmental conditions and nutritional status may results in different physiological disorders which affect the growth of the plants and also the quantity as well as quality of the fruits. The precise and early recognition of physiological disorders is important for the timely adaptation of remedial strategies to reduce the crop loss. Physiological disorders in fruits crops may be due to single factors or multiple factors may be involved in the appearance of physiological disorders. A sound knowledge about the cause of physiological disorder is useful to adopt suitable remedy for the disorder.

Introduction

The abnormal growth behavior or unusual external and/or internal conditions of fruits which results due to adverse environmental conditions and nutritional imbalances are considered as physiological disorders. Physiological disorder is best defined as external or internal malfunctioning resulting from improper environmental or cultural conditions before and/or after harvest. Variation from normal temperature, light, moisture, nutrient, harmful gases, insufficient supply of growth regulators, deficiencies or excesses of nutrient etc. are some of the important environmental and cultural factors of physiological disorders (Fig. 1). Physiological disorders affect the quality as well as quantity of the fruit crops. Detection of precise physiological disorders is not easy and requires a strong knowledge regarding them.

R - Enamel can: The acid resistant, gold coloured enamel treated can are called R enamel cans. It is used for canning of acidic food which have soluble colouring pigments.

R value: R value is a measure of resistance to the flow of heat through a given thickness of a material (insulation) with higher numbers indicating better insulating properties. R-Value is a measure of insulation’s ability to resist heat traveling through it. The higher the R-Value the better the thermal performance of the insulation.

Rabbitto and putridity: The surface taint of the milk caused by Pseudomonas putrefaciens is called rabbitto and putridity.

Racking: An important operation for the wine production in which wine is siphoned off and is transferred to a fresh vat with the help of a false bottom. Racking is repeated decanting to remove the slowly setting cloud of the freshly fermented young wine. It is also called clarification. It is synonym to siphoning.

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.

Introduction

The horticulture sector is contributing over 30 per cent share in agricultural GDP of the country. Presently, India producing about 351.92 million tons of horticultural produce from 28.04 million hectare which has surpassed the food grain production for last five consecutive years (Anonymous, 2023). Horticulture sector has been identified by Government of India also identified horticulture as one of the vital sector for entrepreneurship development, employment generation, livelihood and nutritional security, doubling farmer’s income, achieving SDGs of the United Nations.

Fruits and vegetables have become part of a modern healthy lifestyle as they possess high amounts of minerals, especially electrolytes, dietary fiber, phytochemicals, especially antioxidants, and vitamins (Yahia et al., 2019; Krishnan Kesavan et al., 2023). In consumption, the qualities of products play a critical role in consumers’ choices, which are directly related to health problems (Tian, and Xu, 2022). Bioactive compounds are phytochemical substances present in small quantities in plant materials that can provide biological activity, being generally associated with health benefits, including hepatoprotective, anti-inflammatory, antioxidant, antithrombotic, anticarcinogenic, antidiabetic and prevention of cardiovascular and degenerative diseases (Campoli et al., 2018). Therefore, maintaining high-quality fruits and vegetables is very important for the fruit and vegetable industry. This requires some methods to evaluate the quality of fresh fruits and vegetables during their post-harvest manipulation and storage and before their industrial processing as well (Tian and Xu, 2022).

Introduction

A wide range of agricultural pesticides is currently being used in India. In the financial year of 2015, the size of the crop protection market in India was of about $4.5 billion (FICCI, 2016). A large number of these pesticides are also being used in considerable quantity on horticultural crops, including fruit crops. In general, judicious application of a pesticide following Good Agricultural Practices (GAP) does not leave its residues in crop produces above unacceptable limit. But the GAP recommendations are not available for all crop-pesticide combinations. The usage pattern of pesticides also sometimes gets modified at farm level due to sudden climate changes, and under such situations, the indiscriminate use of pesticides to combat disease and insect complex might result in the contamination of pesticides in fruits.

India, one of the largest food producer countries (I in milk production, II in fruit and vegetable production and III in food grain production at world level), possesses the potential of being the biggest with the food and agricultural sector contributing around 26 percent of the Gross Domestic Product (GDP). It is a paradox that people of the country producing such huge quantities of food including fruits, vegetables, milk, cereals grains etc. are still suffering from many nutritional deficiencies in their diet, and even in some places, the stomachs of people remain unfilled for the want of food. The credit of this would predominantly go to the poor postharvest infrastructure as well as knowhow and accessibility to the facilities. All this makes us one among those countries having largest postharvest losses. The reduction of losses occuring during food handling, processing, storage, distribution and use would be an indirect way of increasing the food production and making the country self-sufficient in nutritional requirements.

(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

Instrumentation and Advanced Analytical Techniques

    1.    Chromatography is defined as an analytical technique where by a mixture of chemicals may be separated by virtue of their differential affinities for two immiscible phases. One of these, the stationary phase, consists of a fixed bed of small particles with a large surface area, while the other, the mobile phase or “eluant”, is a fluid that moves constantly through, or over the surface of, the fixed phase.

    2.    The chromatogram evaluated qualitatively by determining the Rf or retention factor, for each of the eluted substances.

    3.    The Rf is a measure of that fraction of its total elution time that any compound spends in the mobile phase.

    4.    If the liquid phase is a polar substance (e.g. polyethylene glycol) and the mobile phase is non polar, the process is termed normal-phase chromatography

    5.    When the stationary phase is non polar (e.g. octadecylsilane) and the mobile phase is polar, the process is reversed-phase chromatography

    6.    The chromatographic separation of mixtures of large molecules such as proteins may be accomplished by a mechanism called size exclusion chromatography or gel permeation chromatography.

    7.    Separation of certain molecules is accomplished by a mechanism called affinity Chromatography in which specific binding between an antibody (stationary phase) and antigen (analyte) occur.

Jam : It is a product prepared by boiling to a suitable consistency, fruit pulp with sufficient quantity of sugar, acid and pectin so as to set and become firm enough to hold the tissues in position. About 45 parts of pulp are used with every 55 parts of sugar. The finished product should not contain less than 68 per cent total soluble solids.

Jelly : Jelly is prepared by boiling the fruit pectin extract with sugar in the presence of appropriate amounts of acid so as to set into a clear gel. A perfect jelly is transparent, devoid of haziness or any suspended material well set, but not too stiff and should have original flavour of the fruit. When cut it should retain its shape and show a smooth cut surface.

Marmalade : It is a fruit jelly like product in which slices of fruit or peel are suspended in the set gel. Mostly they are prepared from citrus fruits like oranges, lemons etc.

Modern agriculture requires certain precise information on pattern of rainfall, temperature, occurrence of drought and flood etc. for formulating required strategy for crop production. It also requires knowledge about agro-climatic conditions of the region for deciding a planned cropping pattern. Therefore climatic classification and delineation of agro-climatic zones would be imperative for a country or state.

Climatic factors like increase in temperature, carbon dioxide (CO₂) concentration, moisture, and other factors directly or indirectly affect agriculture, which have been elaborately dealt in previous chapters. Climate change causes weather variability that may result in low production, hike in price of agricultural commodities including food grains, vegetables, fruits, meat, egg and milk. It is now realised that climate resilient agriculture (CRA) will be imperative to reduce the vulnerability of agriculture to the climate change.