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Fruits and vegetables are an important category of horticulture crops grown in our country. India is the second-largest producer of fruits and vegetables in the world, with a total production of about 302.80 million MT (2021-22), surpassing even food grain production in the country. However, due to their perishable nature, a large quantity of fruits and vegetables is wasted due to inadequate facilities for post-harvest handling, storage, and processing. Though, during the last 10-12 years, the post-harvest losses in fruit and vegetables have declined from about 6-18 % in 2009-10 to 5-15 % in 2021- 22, but still, in physical terms, about 19.33 million MT of fruit & vegetables worth about Rs 58013.71 crores is lost in different channels from harvest to consumption. Processing of horticultural crops for value addition is thus an important alternative for utilizing surplus, reducing wastage, and checking such loss to ensure remunerative returns. The creation of human resources in processing and value addition is thus urgently needed. Preparation of a manuscript dealing with basic aspects and practical exercises on processing horticultural crops for undergraduates and postgraduates in horticulture, post-harvest technology, and food science & technology is thus a need-based approach in this direction. The work on the development of an e-course on different subjects was undertaken by the Indian Council of Agricultural Research (ICAR) New Delhi in 2010-12 for the development of e-courses under the NAIP (National Agricultural Innovation Programme) project involving nationwide experts. Accordingly, an e-course on the Processing of Horticultural crops based on the syllabus of the 4th Deans Committee report was developed for the students of B Sc (Hons) Horticulture in the country. The course is available online at http:// ecoursesonline.iasri.res.in/course/index.php?categoryid=20. Fortunately, the course contents have also been included in the sixth Deans Committee syllabus for the course on processing and value addition of horticultural crops taught in different SAUs and Horticulture Universities.

Introduction Fruits and vegetables are an important part of the human diet as they provide the necessary nutrition, essential minerals, vitamins, antioxidants, dietary fiber, etc., required for maintaining proper health. India is the second largest producer of fruits and vegetables in the world after China. Comparison of area under horticultural crops during 2011-12 and 2021-22 indicate substantial improvement from 18.5 million ha to 27.6 million ha with a simultaneous increase in production from 215.04 million MT to about 333.25 million MT respectively in the country within a span of just one decade (Table 1.1). The credit for this spectacular growth in area and production goes to the sustained efforts of the central and state governments for the launch of several farmers’/ growers’ welfare schemes viz., National Horticulture Mission (NHM), Horticulture Mission for Northeast and Himalayan states (HMNEH), Mission for Integrated Development of Horticulture (MIDH); R&D support by the ICAR and State Agriculture & Horticulture Universities, extension agencies/Krishi Vigyan Kendra and proactive farmers and orchardists. However, the increase in production has still not kept pace with the improvement in infrastructure for post-harvest handling, management, processing, and value addition. Various studies still indicate that under normal conditions more than 15-20% of the produce goes to waste from production to consumption which in monetar terms accounts for huge economic losses. A recent study sponsored by the Ministry of Food Processing Industries Government of India and conducted by NABARD Consultancy Services has indicated that about 19.33 million MT worth Rs 58013.71 Crores of fruit & vegetables goes to waste annually as postharvest loss (4.87-15.05%) in various channels from harvesting to consumption (NABCONS,2022). The condition becomes even worse when there is a glut in the market, road blockades, or seasonal vagaries, and farmers are forced to leave their produce in the field itself without harvesting or dispose it at throwaway prices. Such a situation can, however, be controlled by diverting thisproduce to processing for conversion into a number of value-added products for its later use in human consumption. Thus, processing and preservation of horticultural crops have now become a necessity rather than a luxury.

Introduction Food Pipe Line refers to a post-harvest system that deals with ensuring the delivery of a crop/commodity from the time and place of harvest to the time and place of consumption, with minimum loss, maximum efficiency, and maximum returns to all concerned including the grower, processors, and consumer. The term ‘system’ represents a dynamic, complex aggregate of logically interconnected functions or operations within a particular sphere of activity. The term pipeline refers to the functional succession of various operations but tends to ignore their complex interactions. Stages of the post-harvest system The food commodities broadly undergo different stages/operations of postharvest systems right from harvest to consumption. However, the applicability of different stages varies with the type of crop. Different unit operations involved in the post-harvest system of food commodities are as under: 1. Harvesting 2. Threshing (food grains, pulses and oilseeds) 3. Drying (food grains, pulses and oilseeds) 4. Collection, Sorting, grading, packaging (Horticultural Crops) 5. Transportation and distribution 6. Storage (Godowns, cold stores, CA stores) 7. Processing

Introduction Food preservation refers to an art or science which deals with the process of prevention of decay, deterioration or spoilage of food commodity to allow it to be stored in a safe condition for future use. All foods gradually undergo deterioration or spoilage from the time immediately they are harvested or manufactured. Some commodities spoil rapidly, while others can keep longer but for limited periods. The basic purposes of food preservation are: 1. Extension of shelf life of foods thus increasing the supply 2. Ensuring the availability of seasonal foods throughout the year 3. Adding variety to the diet 4. Saving time by reducing preparation time and energy 5. Stabilizing farm prices and prices of food 6. Improving the nutritional qualities The food spoilage can be caused due to growth and activity of micro-organisms, insects or rodents, action of enzymes, chemical reactions and physical changes that takes place during processing, drying, or freezing etc. Classification of Food Depending upon the type of spoilage and level of perishability, the foods are classified into three broad categories:

Introduction: Food processing involves different steps from receiving raw material, preparing for product manufacture, and packaging to storage. All these steps are called unit operations. They are broadly categorized as raw material preparation (receiving, sorting, grading, washing, peeling, blanching, slicing, cutting, dicing etc), processing (canning, drying, pulping, juicing, product manufacture like jam, jelly, preserves, candies, pickling, sauce making, etc.) and post-production handling including packaging and storage. A brief detail about each unit operation is discussed as under: 1. Raw Material Handling Material handling includes varied operations such as hand or mechanical harvesting on the farm, transportation in trucks or refrigerated vehicles of perishable produce to the market or to the processing plant or to store/godowns. For conveying, a wide variety of mechanical conveyors is used depending on the type of material. Common conveyors used in the processing plant include screw conveyors, bucket conveyors, belt conveyors and vibratory conveyors. Throughout these operations, care is taken to maintain sanitary conditions, minimize bruises and product loss, maintain raw material quality like physical appearance, and vitamin contents, minimize microbial growth and minimize other detrimental changes to the product quality during handling etc. It also includes other unit operations like receiving, cleaning/washing, sorting, grading, peeling, halving, slicing, blanching etc for preparation of fruit and vegetables for processing.

Introduction For setting up a fruit processing plant, the following cost and non-cost factors affecting the plant’s location are considered. Cost factors include raw material cost, transportation cost, cost of land, building and machinery, utilities cost, taxes, and insurance costs. At the same time, non-cost factors consisting of wages, salaries and incentives, market potential, community attitude, cost regulation, quality of life (school, living, recreation for workers, etc.), and environmental impact are taken into consideration. The main objective for the selection of the site for the processing unit is to minimize the sum of all costs. To minimize the cost, one should think not only the today’s costs but about long-term costs as well. Plant Layout The advantages of good plant layout are: - i. Saving in floor space ii. Increased output iii. Fewer production delays iv. Reduced material handling cost v. Greater utilization of machine and manpower vi. Easier and better supervision vii. Less congestion and confusion viii. Better appearance and more sanitary condition of work areas ix. Reduced risk to the health and safety of employees

Introduction Processing fruit and vegetables by applying heat is one of the most important methods of preservation as it exerts a positive preservative effect on the foods by destroying spoilage causing micro-organisms, enzymes, insects, parasites, etc. Heat processing also improves the availability of nutrients by improving digestibility, releasing vitamins like bound niacin, destroying anti-nutritional factors like trypsin inhibitor in some legumes including soybean, causing gelatinization of starches, and producing shelf-stable products. However, heating also causes some alteration or destruction of the sensory quality of fresh foods like changes in flavor, color, taste, and texture as a result, heatprocessed foods are perceived to have different sensory qualities than fresh produce. Preservation by heat (thermal processing) involves heating foods in hermetically sealed containers for a specific time at a particular temperature to eliminate/kill/inactivate the microbial pathogens that endanger public health and micro-organisms and enzymes that deteriorate food during storage. Most of the raw material used for canning is usually contaminated with different species and strains of bacteria, molds, and yeasts undergoing different stages of growth (lag phase, log phase, stationary phase, vegetative phase, sporulation phase, etc.,). Amongst these, bacterial spores are more difficult to inactivate. Thus, the criteria for heat processing chosen to inactivate the spores are also presumed to be capable of inactivating all other forms of microorganisms. Unlike fruits, most vegetables being low acid or even non-acid require a severe heat treatment to kill most bacteria. It is, therefore, necessary to work out the proper time and temperature combination for each category of food to ensure complete preservation.

Introduction The term canning refers to a process in which the food is heated in hermetically sealed containers at a specific temperature for a specific time to eliminate microbial pathogens that endanger public health; and microorganisms & enzymes that deteriorate food during storage. The credit for the invention of canning goes to a French confectioner Francois Nicholas Appert, who was awarded a prize in 1809 by the French government for developing a new method of heat preservation of food in a sealed container and after whose name the process of canning has also been named as Appertization. In 1810 Nicholas Appert published the first book on canning entitled “The Art of Preserving Animal and Vegetable Substances for Many Years.” which is the first known work on canning. The work of Appert consists of packing food in glass bottles, closing them with corks, and heating the container in boiling water for several minutes depending upon the type of the food. Although the developed technique was used to preserve different types of food, the actual reason for the prevention of spoilage was known only after the work of Louis Pasteur (1864) who discovered that food spoilage was caused by microorganisms that were destroyed at elevated temperatures and the technique was known as Pasteurization. This understanding helped to form a scientific basis for establishing and revolutionizing the canning industry. Canning of fruits on a commercial scale was introduced in the USA in 1817 by William Underwood. The old phrase ‘necessity is the mother of invention’ suits well for the development of the canning industry during wars. The Civil War in America and the Great European War of 1914 also gave impetus to the development of a canning industry to meet enormous requirements of food for the fighting forces.

Introduction Fruit juice and beverages comprise naturally extracted juices, drinks, ready to serve (RTS) beverages, carbonated juice drinks, nectars, squashes, cordials and appetizers, etc. These products are highly refreshing, thirst-quenching, appetizing and nutritionally superior to many synthetic and aerated drinks. Fruit juice is the natural liquid expressed from the edible portion of the fruit. Fruit juices are generally extracted from fruits in several ways, depending on their structure and composition. Soft fruits such as berries or tomatoes can be pressed in a fruit press or pulped by using a juicer attachment to a food processor. Citrus fruits are usually reamed to extract the clear juice. Harder fruits, such as pineapple, are peeled, pulped and pressed to extract the juice. Apple and pear fruits are crushed in a fruit grater and pressed in a hydraulic/ basket press to extract a clear juice. Passion fruit juice is prepared by using a pulper-finisher that separates the skin and seeds from the pulp. The fruits like mango, guava, apricot, peach etc from which the clear juice extraction is difficult are passed through the pulper to make pulp and then the pulp is utilized for preparation of juice, fruit drinks and ready to serve beverages. The composition of juice is unaltered during preparation and preservation while for fruit beverages like drinks, squashes, cordial etc the fruit juice or pulp, sugar, acid, colour, flavour etc are mixed in appropriate proportions to a desirable taste. Apple juice, orange juice, mango squash, guava drink, pineapple juice and squash, mixed fruit drink, mango nectar etc are the commercial products available in the market.

Introduction The addition of sugar in foods acts as a preservative when its concentration is above 66%. It absorbs most of the available water and restricts the availability of moisture required for the growth of microorganisms. Sugar adds value to the product by imparting sweetness as well as body to these products. When sugar is boiled with acid and fruits, it is hydrolysed into glucose and fructose, the degree of inversion depending upon the pH and duration of boiling. Because of the inversion of sucrose, a mixture of sucrose, glucose and fructose is found in products like jam, jelly, marmalade, preserves and candies. Jams, jellies and marmalades constitute an important class of fruit products preserved by using sugar as the method of preservation. Apple jam, mango jam, pineapple jam, strawberry jam and mixed fruit jam prepared by using the pulp of two or more fruits are quite common. Similarly, guava jelly and orange marmalade are also examples of such products. A fruit preserve is made from properly matured fruit by cooking it whole or in the form of large pieces in heavy sugar syrup, till it becomes tender and transparent. A fruit impregnated with cane sugar and glucose, followed by subsequent draining and drying is called a candied fruit (Fruit candy) e.g. petha candy, ginger candy. While candied fruit covered or coated with a thin transparent coating of sugar, which imparts to it a glossy appearance is referred to as a glazed fruit. When candied fruit is coated with sugar crystals either by rolling it in powdered sugar or by allowing the sugar crystals from glucose syrup to deposit on it, it becomes a crystallized fruit (Crystallized Candy). The use of high concentrations of sugar in these products acts as a preservative. Products like Petha candy, aonla preserve, candied citrus peels, ginger candy, ginger in syrup, bael, pineapple and carrot preserve are the commercial products in this category.

Introduction Many chemical substances are added to the food for functional purposes and in many cases, these are found to occur naturally in some foods. When these substances are added to the foods, they are known as food additives. An additive is defined as a substance or mixture of substances other than basic food ingredients that are present in a food as a result of any aspect of production, processing or packaging. Additives may be intentional as well as unintentional. Intentional additives are substances deliberately added to perform a specific function and to increase the shelf life of the products while unintentional additives have no intended function in the finished product but become part of that particular product. The food additives having significance in fruit and vegetable preservation and their mode of action are discussed as under: Objectives of adding an additive 1. To reduce wastage and improve keeping quality e.g., the addition of potassium meta-bisulphite in squashes, benzoate in sauces, sodium propionate in bread and sorbic acids in cheese etc., 2. To improve and maintain nutritive elements e.g., addition of vitamins for enrichment, addition of vitamin D to milk, addition of iodine to salt etc. 3. To enhance the quality and consumer acceptability of the product e.g., the addition of colouring agents, emulsifiers, thickeners etc. 4. To facilitate the preparation of foods e.g., the addition of acid to beverages, sugar in jams, jellies etc.

Introduction Preservation by using common salt, spices and vinegar is a common method for the preparation of pickles, sauce and chutneys. Salt is mostly used as a preservative in pickles in combination with acid. Sodium chloride is used in brines and curing solutions or is applied directly to the food. The quantity of salt necessary to inhibit growth or harm the cells varies with the type of microorganisms. However, the minimum concentration of salt to act as a preservative is about 12%. Salt (sodium chloride) exerts its preservative action by performing the following functions: ? Causing high osmotic pressure resulting in plasmolysis of the microbial cells. ? Dehydrating food by tying up the moisture thus making it unavailabl for the growth of microorganisms. ? Salt lowers the water activity and thus has adverse effects on microorganisms. ? Affecting the solubility of oxygen in the food and thus inhibiting the growth of aerobic microorganisms. ? Salt ionizes to yield chlorine ions, which is harmful to microorganisms. ? Chlorine in sodium chloride is a good oxidizing agent & is, therefore, toxic to microorganisms.  

A. Tomato and Tomato Products Tomato though botanically a fruit is generally considered a vegetable because of how it is consumed. Commercial products from tomatoes include juice, puree, paste, ketchup, soup canned and dehydrated tomatoes. Processing of tomato is now practised from home scale level to large scale enterprise. As a semi-finished product, tomato puree is prepared on a small scale while at a large scale, tomato paste has gained commercial significance. Both puree and paste are used for the preparation of different finished products like ketchup, juice, soup etc. The method for preparation of these products is well standardized, however, some modifications concerning recipes are made in the processing plants owing to variations in the quality of the raw material. The methods for the preparation of different tomato products are discussed as under: - I. Tomato Juice/Pulp Tomato juice is an unconcentrated product consisting of a liquid with a substantial portion of the pulp, expressed from ripe tomatoes with or without the application of heat and the addition of salt. Tomato pulp/juice is the basic ingredient for the preparation of different tomato-based products such as tomato puree, paste, ketchup etc. Fully ripe tomatoes are used for the preparation of tomato juice/pulp. All green, blemished and overripe fruits should be rejected as they adversely affect the quality of the product. The juice obtained from overripe tomatoes is usually thin and unpleasant. The juice should be deep red in colour with a characteristic taste and flavour. The juice shall have about 0.4% acidity expressed as citric acid. Cane sugar (1%) is added to further improve the taste and flavour of the finished product.

Introduction Drying is probably the oldest method of food preservation used for agricultural crops, including food grains, oilseeds, spices, as well as fruit and vegetables. Drying refers to the removal of moisture content from the food to a level at which the activities of food spoilage micro-organisms are inhibited. Therefore, the reduction in water activity of the food as a result of moisture removal is themain principle of preservation by drying. Two commonly used terms for dried foods include low-moisture foods and intermediate moisture foods (IMF). Dried foods or low-moisture foods generally do not contain more than 25% moisture and have a water activity (aw) in the range of 0 to 0.6. Intermediate moisture (IMF) foods on the other hand contain 15- 50% moisture with a water activity (aw) of 0.60 -0.85. Dried grapes (raisins and munacca), apricots, dates, Morchella (Guchhi), bael, chilli, figs, etc. are commercial products prepared by using drying. However, the temperature used for drying is usually insufficient to cause the killing of microorganisms and enzymes, therefore any increase in moisture content during storage due to faulty packaging can also spoil the product. Thus, greater care is required for the packaging and storage of dried products.

Introduction Freezing is one of the oldest and most widely used methods of food preservation, which allows the preservation of taste, texture, and nutritional quality in foods better than any other methods. The freezing process is a combination of the beneficial effects of low temperatures at which micro-organisms cannot grow, chemical reactions are reduced, and cellular metabolic reactions are delayed. Freezing is generally referred to as a unit operation in which the temperature of food is reduced below the freezing point and a proportion of water undergoes a change in state to form ice crystals. Immobilization of water to ice and the resulting concentration of dissolved solutes in unfrozen water cause a lowering of water activity of the food. Thus, reduction in water activity and use of low temperatures coupled with some pre-treatments like blanching is the basis for food preservation by freezing. Fruits such as strawberries, oranges, raspberries, black currants, and vegetables like green peas, green beans, sweet corn, spinach, carrots, sprouts, and potatoes are examples of commercially frozen fruits and vegetables. The frozen food market is one of the largest and most dynamic sectors o the food industry. Despite considerable competition between the frozen food industry and other sectors, large quantities of frozen foods are being consumed all over the world. The frozen vegetable industry mostly grew after the development of scientific methods for blanching and processing in the 1940s. The commercialization history of frozen fruits is older than frozen vegetables. The commercial freezing of small fruits and berries began in the eastern part ofthe United States in about 1905.

Introduction Plantation crops are high-value industrial crops grown in the tropics and coastal areas. They have great potential for utilization of wasteland like rainfed dry land, hilly, arid, and coastal areas to provide nutritional security; earn foreign exchange, and ensure livelihood security. The major plantation crops grown in India are tea (Camellia sinensis L), coffee (Coffea arabica L.), rubber (Havea brasiliensis), coconut (Cocos nucifera), areca nut (Areca catechu L.), oil palm (Elaeis guinensis), cashew nut (Anacardium occidentale L.) and cocoa (Theobroma cacao L.). India is the leading producer of most of these plantation crops. Among all fruit crops, processing plays an important role in plantation crops as they are generally consumed only after processing. In addition to primary products, some by-products from these crops also have various commercial uses. Coconut, areca nut, cashew nut, black pepper, and cardamom are known as smallholder plantations whereas, crops like rubber, tea, and coffee are known as estate crops or conventional plantation crops. Processing aspects of some of these crops are discussed here:

Introduction The food that has been damaged or has undergone changes so as to render it undesirable/unacceptable/unfit for human consumption is termed as spoiled. Spoilage of processed products is mainly caused by the action of micro-organisms and due to the physical or chemical changes. The reasons for microbial spoilage include under processing, inadequate cooling, contamination from leakage through can seams and pre-process spoilage. In under-processed cans (receiving low heat treatment), large number of different types of micro-organisms are expected to be involved in spoilage. Causes of Food Spoilage Food spoilage or deterioration may be described as loss of weight, softening, souring, rotting, wilting, moulding or a combination of one or more forms. The major causes of food deterioration are: biotic and abiotic factors. A. Biotic Factors 1) Microbial spoilage (yeast, mould, bacteria) 2) Enzyme action (activities of enzymes present in foods) 3) Insect and rodent damage (attack of insects, rodents and parasites)

1. Introduction Quality makes the product what it is. Quality is how well a product or service satisfies the needs of the customer. Quality can be interpreted in several ways, such as conformance to the standards, meeting customers’ preference/ satisfaction for desired quality attributes, degree of excellence, zero-defect products, etc. The quality standard of fresh and processed fruit or vegetable products varies with their intended use. For marketing purposes, size, attractiveness, maturity, organoleptic quality and freedom from defects are to be kept in mind in fresh and processed fruit or vegetable products. During the processing of fruit or vegetables into value-added products, colour, flavour and texture also become important. Therefore, Quality is defined in different ways, such as: i. Quality is a measure of the degree of excellence or degree of acceptability by the consumer. ii. Quality is also defined as the combination of attributes or characteristics of the products that have significance in determining the degree of acceptability of the product to a user.

Introduction Food laws and regulations are the legal standards of quality that regulate the manufacture, storage, distribution, sale, and marketing of food products. The major objectives of enacting the food laws and regulations are i) to maintain the quality of food produced ii) to safeguard the health of the consumers iii) to prevent exploitation of the consumer by the sellers and iv) to establish a standard of quality for different food products. In 2006 the government of India enacted the Food Safety and Standards Act, 2006 (FSSA) to consolidate all laws relating to food and to establish the Food Safety and Standards Authority of India (FSSAI) for laying down science-based standards for different articles of food and to regulate their manufacture, storage, distribution, sale and import to ensure availability of safe and wholesome food for human consumption. Various food laws enacted in our country before 2006 for different categoriesof food were: • PFA (The Prevention of Food Adulteration Act),1954 (Act 37 of 1954) • FPO (Fruit Products Order),1955 • Meat Food Products (Control) Order,1973 • Vegetable Oil Products (Control) Order,1998 • The Edible Oil Packing (Regulations) Order,1998 • Solvent Extracted Oil, De-oiled Meal and Meal and Edible Flour (Control) Order,1967

Introduction In India, the government policy regarding the import and export of processed fruits is primarily regulated by the Agricultural and Processed Food Products Export Development Authority (APEDA), which requires exporters to register with them to export notified processed food items, including processed fruits, and implement various export promotion schemes to facilitate this trade; the overall goal is to boost the export of agricultural and processed food products through the Agriculture Export Policy (AEP). 1. Key features ofAgriculture Export Policy (AEP) i. Governing body: APEDA, established under the Agricultural and Processed Food Products Export Development Authority Act, 1985. ii. Registration required: All exporters of processed fruits are required to register with APEDA to export their products.

The following equipment and types of machinery are generally used in the food processing plant which specifically deals with the processing of fruits and vegetables; I. Machinery/Equipment for general purpose 1. Weighing Balance (Precision balance for chemical and heavy duty for fruits/raw material) 1-500mg, 1kg,10kg,100kg. 2. Cutting Knife (SS), coring knife, pitting knife, peeling knife 3. Abrasive peeler (carborundum crystal) for potato,carrot,ginger etc., 4. Working Table with Stainless steel/Aluminium top 5. Buckets/ Water tubs/jugs (Plastic/Stainless Steel) 6. LPG/Diesel Bhatti/furnace/Stove 7. Utensils/Bhagona (Aluminium /Stainless steel); 10, 50,100 kg capacity 8. Spoon, ladle (heavy duty), grater,` 9. Belt conveyors

Fruit firmness is an important indicator of maturity. During ripening, fruits may soften and become too soft at the overripe stage. The changes are detected by pressing the fruit in between hands or by using devices like a pressure tester or texture analyzer to measure the texture of fruits and vegetables. Commonly used pressure testers to measure the firmness of fruits and vegetables are the Magness–Taylor Pressure Tester and Penetrometer. Principle: For the measurement of pressure, the maximum force required to rupture the sample is measured by pushing a cylindrical metal probe into the sample to a given depth. The Magness-Taylor pressure tester can be used to determine the softening of fruits during maturity. In this instrument 10 lb or 30 lb force springs are available. Each of them is provided with one or two punches of 5/16 or 7/16 inch in diameter. The plunger of larger diameter is used on softer material, while; the smaller one is used for firmer material. Procedure 1. Select the pressure tester according to type of fruit 2. Remove a thin portion of the skin in case of waxy fruits

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

Measurements of sugars in the fruit can indicate the stage of maturity. Total soluble solid (TSS) contents can give a reliable measure of the sugar and other water-soluble components in fruits, vegetables, and their products such as juice, squash, jam, preserve, candy, sauce, ketchup, etc., In climacteric fruits, carbohydrates accumulate during maturation in the form of starch, and as the fruit ripens the starch is broken down into sugar. In non-climacteric fruits, sugar tends to accumulate during maturation. The presence of sugars, acid, ascorbic acid, and other water-soluble components in the fruit, vegetable, and their products are measured as total soluble solids. Principle Soluble solids can be determined using a refractometer which measures the refractive index or a brix hydrometer which measures specific gravity. A Brix hydrometer is used to determine the percentage of brix in syrup while an Abbe refractometer gives both refractive index as well as degree brix. The Refractive index of the test solution is measured at 20°C using a refractometer and the soluble solid content is calculated by the use of tables correlating the refractive index with soluble solids.

The inorganic residue remaining after the destruction/burning of organic matter in foodstuffs is called ash. Ash contents in food commodities roughly represent the mineral contents, however, some minerals are likely to be lost due to volatilization or some interaction between constituents during ashing. Estimation of ash content is also used as a measure to judge the quality of fruit products. The presence of high ash content or low alkalinity of the suggests the presence of adulterants in the sample. Similarly, the presence of a high amount of acid-insoluble ash indicates the presence of sand and other silicious matter in the food products. Principle Organic matter is burnt off at as low a temperature as possible. Heating is done in stages, first to char the product thoroughly and finally to ash it at 550ºC in a muffle furnace. The inorganic material left after burning organic matter is cooled and weighed. Apparatus * Silica Crucibles * Muffle furnace * Desiccator * Balance

Most of the fruit, vegetables, and their products contain acid or a mixture of acids. These acids are mainly responsible for the tartness or sour taste. The level of acidity is estimated to measure the degree of tartness/sourness in the product. Principle Acidity in the sample is measured by titrating a known volume of sample against a standard alkali solution of known concentration using phenolphthalein as an indicator. The appearance of a light pink color indicates the endpoint of titration. However, for highly colored products like tomato sauce/ketchup, jamun juice, Rhododendron juice, mixed fruit jam, etc., accurate determination of endpoint may be difficult by using an indicator. Therefore, for such samples, acidity is measured by using electrometric methods i.e. titration to a predetermined pH value, or the sample is further diluted with distilled water to mask the interfering color. The level of titratable acidity is expressed in terms of the predominant acid. Different fruits, vegetables, and their products have different predominant acids. A list of some products having predominant acid is shown as under:

pH is important as a measure of active acidity which influences the flavour and palatability of the product and affects the processing requirements. This is an indicator of the acidity or alkalinity of the solution. It is also taken as the measure of the sourness or tartness of the given sample. The pH of a solution varies from 0 to 14. Solutions having a value of pH ranging from 0 to 7 on the pH scale are termed as acidic and the value of pH ranging from 7 to 14 on the pH scale are known as basic solutions. While, solutions with a pH value equal to 7 on the pH scale are known as neutral solutions. Samples with a pH value equal to 0 are known to be strongly acidic. Further, the acidity decreases as the value of pH increases from 0 to 7 whereas, solutions with the value of pH equal to 14 are termed as strongly basic solutions. Most fruits have a pH value ranging between 3-4, with citrus fruits exhibiting a pH of up to 2.0. Vegetables may exhibit a pH of up to 6.0, as such they are classified as non-acid or low-acid foods. Based on pH value, most fruits, vegetables, and their products are classified into four arbitrary groups such as low acid (5.3 and higher); medium acid (5.3-4.5), acidic (4.5-3.7), and high acid (3.7 and lower). pH value of some fruits, vegetables, and their products is given as under:

In fruits, vegetables, and their products, the sugars are estimated as reducing sugars, non-reducing sugars, and total sugars. Reducing sugars in fruits and their products represent glucose and fructose. A combination of reducing and non-reducing sugars gives total sugars, whereas non-reducing sugars mainly sucrose are calculated after deducting the value of reducing sugars from the total sugars as invert sugar and multiplying the remainder with a factor of 0.95. Many fruit, vegetables, and their products like jam, jelly, juice, preserve, candy, fruit toffees, etc., containing substantial amounts of sugars, are estimated as a routine by using Lane and Eynon’s method using Fehling’s solution. However, for products having a smaller quantity of sugars, more precise methods like colorimetric methods can be used. Method: Lane and Eynon’s Method Principle: Invert sugar reduces the copper in Fehling’s solution to red, insoluble cuprous oxide. The sugar content in a food sample is estimated by determining the volume of the unknown sugar solution required to completely reduce a known volume of Fehling’s solution. Glucose, fructose and other] sugars capable of reducing oxidizing agents are called reducing sugars and this property is used for the estimation of sugars.

Ready -to -Serve (RTS) drink is a type of fruit beverage that contains at least 10% fruit juice/pulp and 10o Brix total soluble solids with acidity ranging between 0.3-0.5%. The product is not diluted before serving like squash; hence it is called a ready-to-serve beverage. The product can be preserved by using 70 ppm SO2  or 120 ppm benzoic acid. Mango, orange, guava, lemon, lime, litchi, kiwi fruit, apricot, pineapple, etc., fruits are used for making RTS beverages. For lime & lemon drinks minimum level of juice content is 5% as per Indian Food Laws. Recipe: As a general guideline, the following recipe is used for the preparation of ready-to-serve drinks: Procedure i. Select fully mature and ripe fruit like mango, guava, apricot, kiwi, etc., and wash thoroughly. ii. Some fruits like mango, kiwi, pineapple, and litchi are peeled before heating. Apricots, guava, plums etc are not peeled. Place fruit after peeling in a pan/pressure cooker and boil till softening

Fruit, vegetables and their products are important sources of ascorbic acid. Aonla, guava and citrus fruits are good sources of Vitamin C (Ascorbic acid).Ascorbic acid is sensitive to heat, light and oxygen but is stable in acidic  media. The methods for estimation of Ascorbic acid are based on the reduction of 2,6 -dichlorophenol - indophenol dye by ascorbic acid and those based on the reaction of dehydroascorbic acid with 2,4- dinitrophenylhydrazine. However,the 2,6 -dichlorophenol - indophenol dye reduction method is most commonly used in the estimation of ascorbic acid in fresh fruit and vegetables and their processed products. 2,6 dichlorophenol - indophenol visual titration method The dye, which is blue in an alkaline solution and red in an acid solution, isreduced by ascorbic acid to a colorless form. The reduction is quantitative and specific for ascorbic acid in solutions in the pH range of 1-3.5. Reagents i. 3% Metaphosphoric acid (HPO3) solution:Dissolve 3g sticks/ pelletsofMetaphosphoric acidin a volumetric flask and make volume to 1oo ml with glassdistilled water.

Fruit nectar is a type of fruit beverage that contains not less than 20% fruit juice or pulp, not less than 15o B total soluble solids and acidity ranging between 0.3-0.5 % but not exceeding 1.5%/. For orange and pineapple nectar, the fruit juice shall not be less than 40%. The product is preserved by heat processing/ thermal processing, as such no chemical preservative is permitted in nectars. Unlike squashes, fruit nectar is served chilled as such without any dilution. Mango, guava, pineapple, papaya, jamun etc., are the most suitable fruits for making nectar. Recipe: As a general guideline, the following recipe is used for the preparation of fruit nectar: Procedure i. Select fully mature and ripe fruit and extract pulp as discussed under fruit pulp making but do not add any chemical preservative.

The use of salt (Sodium Chloride) in food products is an important method of preservation. It not only imparts taste to the products but also helps in checking spoilage of fruit products. Salt is added to pickles, sauces, chutneys, ketchup, and many other products. Food Safety & Standards Regulation has specified the maximum limit of salt in different products. Therefore, the estimation of salt content in food products is considered as an important attribute in food quality control. Direct Titration Method Direct titration (Mohr’s) method is used for the determination of salt content in food products as a routine quality control. In this method, the sample is titrated against a standard solution of silver nitrate for the estimation of salt. Reagents 0.1 N NaOH, Phenolphthalein 1% indicator solution 0.1N Silver nitrate (AgNO3) 5% Potassium Chromate

Sodium benzoate is added to many fruit products to act as a preservative for the extension of the shelf life. Food Safety and Standards Regulations have specified the maximum level of sodium benzoate (Benzoic acid) in different products like sauce, ketchup, pickles, squash, etc. Therefore, the estimation of sodium benzoate (benzoic acid) in such products is considered a routine quality control procedure. Principle Benzoic acid which is sparingly soluble in water is converted into watersoluble sodium benzoate by the addition of NaOH in a sample containing sodium chloride solution. When the Sodium Benzoate solution is acidified with excess HCl, water-in-soluble benzoic acid is formed which is extracted with chloroform. The chloroform is removed by evaporation and the residue containing benzoic acid is dissolved in alcohol and then titrated with standard NaOH.

Sulphur dioxide is used as a preservative in many fruit and vegetable products. It can be added either in the form of potassium metabisulphite or by exposingthe product to sulphur fumigation by burning sulphur powder. Food safety and standards regulations have specified the maximum limit of sulphur dioxide in the finished products. Products having sulphur dioxide content exceeding the limit are considered not conforming to Indian Food Laws. Therefore, the estimation of sulphur dioxide in food products is considered an important attribute for quality evaluation. Principle Sulphur dioxide added to the food products may exist as undissociated sulphurous acid, as free bisulphite ions, as free sulphite ions and/or as combined SO2 in the form of hydroxy sulphonates. Sulphur dioxide is measured as free or total SO2. Free SO2 is measured by direct titration with iodine. In the estimation of total SO2, the combined SO2 is liberated by treatment with excess alkali at room temperature, followed by subsequent acidification to prevent recombination and titration with iodine. The method used is known as the Modified Ripper Titration Method.

Starch is the storage form of carbohydrates in plants which is abundantly found in roots, tubers, stems, fruits, and cereals. It is a polysaccharide made up of glucose monomers with a chemical formula of (C6H10O5)n. Starch is composed ofamylose and amylopectin. The linear polymer amylose is the most basic form of starch while amylopectin is the branched form. Foods that are high in starch content are a good source of nutrition. Food starches are used in the food industry as thickeners and stabilizers. During the ripening of fruits, the starch is converted into sugars. Therefore, the presence of starch in fruits is used as an indication of maturity and ripening. Principle: For estimation of starch contents, the sugars present in the sample are leached out and starch is hydrolyzed using either acid or enzymatic hydrolysis. Stach is then calculated as invert sugars. Starch content by Acid Hydrolysis method Reagents: Ethanol 95%, /50%,Concentrated HCl, Concentrated H2SO4, 1N NaOH solution, Phenolphthalein indicator, 10% alcoholic solution of Alphanaphthol.

The term canning refers to a process that involves heating foodstuff in hermetically sealed containers for a specific time at a specific temperature to eliminate microbial pathogens that endanger public health; and microorganisms and enzymes that deteriorate food during storage. Principle of canning: Destruction of micro-organisms causing spoilage, within the sealed containers using heat. Canning Process Preparation of food commodities for canning consists of selection of commodities, washing, sorting, grading, peeling, halving, blanching, filling into cans, filling hot syrup or brine, exhausting, double seaming, Sterilization/ processing, cooling, storage, etc. Raw material selection Fruits should be ripe but firm, evenly matured, and free from blemishes, insect damage, and malformation. Apple, pear, peach, and banana harvested at the mature stage are preferred for canning.

Fruit pulps are semi-finished products that are used for manufacturing finished value-added products like jam, ready-to-serve beverages, squash, appetizers etc. According to Food Laws, pulp refers to an unfermented but fermentable product, pulpy, turbid or clear, obtained by a mechanical process from sound ripe fruits/vegetables. These are preserved either by heat processing or by using chemical preservatives. The maximum preservative permitted under Indian Food Laws is 1000 ppm sulphur dioxide added in the form of potassium metabisulphite. Mango, guava, apple, pineapple, papaya, bael, guava, peach, plum, apricot etc., are the most suitable fruits for making pulp for use in finished product preparation. Procedure i. Select fully mature and ripe fruit like mango, guava, apple, peach, apricot, kiwi, etc., and wash thoroughly.

Squash is a type of fruit beverage containing at least 25% fruit juice/pulp, not less than 40% total soluble solids (TSS), about 1-1.5% acid and not exceeding 350ppm sulphur dioxide or 600ppm sodium benzoate. Squash is diluted by adding cold/chilled water before serving (1:3). Mango, orange, lemon, lime, litchi, guava, pineapple, jamun, plum, apricot, rhododendron petals etc., are used for making squash. Potassium metabisulphite (KMS) is generally used as a preservative, whereas sodium benzoate is used as a preservative in squash made from coloured fruits like plum, jamun, phalsa and rhododendron petals. Recipe: A generalized recipe for the preparation of squashes from different fruits as a general guideline is as under:

Cordial is a sparkling, clear, sweetened fruit juice beverage from which pulp/ fibrous material has been removed completely. It contains at least 25% fruit juice, 30% total soluble solids (TSS), 1.5% acid and 350 ppm sulphur dioxide. Lemon and lime are the most suitable fruits for making cordial. Recipe: The recipe for the preparation of cordial as a general guideline is as under: Extract the juice from lime or lemon as in squash and store in glass bottles after adding potassium metabisulphite @ 1.0 g/kg of the juice. Allow the juice to settle for a month. Decant the clear juice without disturbing sediments and strain it through a fine muslin cloth. Prepare syrup by mixing sugar with water, boil, strain and allow to cool. On cooling, mix juice in syrup and strain the cordial through muslin cloth if necessary. Add KMS and fill into bottles. Stor in a cool and dry place.

Jam is prepared by boiling the fruit pulp with a sufficient quantity of sugar to a thick consistency, firm enough to hold fruit tissues in position. For the preparation of jam, not less than 45 parts of fruits are used for every 55 parts of sugar. The jam prepared by using two or more fruit pulps is called mixed fruit jam. Apple jam, apricot jam, mango jam, guava jam, pineapple jam, and mixed fruit jam prepared by using the pulp of two or more fruits are quite common. According to Food Safety & Standards Regulations,2011 the minimum TSS in the Jam shall not be less than 65%(w/w). Earlier the minimum limit was 68% (w/w) Raw material, ingredients and utensils required 1. Fruits like mangoes, guava, apples, apricots, plum, peaches and kiwi etc singly or in combination 2. Stainless steel knives, de-corers, ladle, utensils for cooking and mixing, glass bottles (Jars), LPG or Diesel Bhatti, bucket/tub for washing, Stainless steel sieve, Steam Jacketted Kettle, Boiler (for the commercial unit) etc. 

Jelly is prepared by boiling the fruit with or without the addition of water, straining the extract, and mixing the clear extract with sugar followed by cooking the mixture to a stage at which it will set to a clear gel. The jelly should be transparent, well set, but not too stiff, and have an original flavour of the fruit. It should be attractive in colour and should keep its shape when removed from the mould. As per FSSAI specification, the quantity of fruit and soluble solids in the final product (jelly and marmalade) shall not be less than 45 and 65 per cent (w/w) respectively. Jelly is made from fruit extract while jam is made from fruit pulp, therefore, jelly in contrast to jam is considered to be transparent and clear in appearance. Guava jelly is the most common commercial product. Jellies: In the preparation of jellies, pectin is the most essential constituent which help in making the gel. Since, pectin is present in the cell walls of fruits as such fruit peel, whole or fruit slices along with a small quantity of water are gently boiled to extract the maximum proportion of pectin solution in the water extract. This water extract is used for the preparation of jelly.

Marmalade is a fruit jelly in which the slices of peel are suspended. The marmalades are prepared generally from citrus fruits like orange and lemon. The pectin and acid contents of the marmalades should be kept slightly higher  than that for jellies. Citrus marmalades are of two types: i) Sweet marmalade and ii) Bitter marmalade. Procedure Preparation of fruit extract: After washing the fruit, remove the outer yellow flavedo portion of the peel of citrus fruits thinly which contains colouring matter and volatile oils, whereas the inner white albedo portion contains pectin. The thin yellow peel is cut into fine shreds with a knife, or on a shredding machine, and the shreds are boiled and drained to remove the bitterness. The sliced or crushed fruit is boiled gently by simmering with 2 or 3 times its weight of water to extract the pectin. While it is being boiled, a teaspoonful of the clear extract is taken from the pan and tested with alcohol for its pectin content. The process usually takes 30 to 45 minutes.

Fruit chutney is a product made in the same way as jam except that spices, salt, and acid (vinegar) in addition are added. The total soluble solids in chutney are] also less than that of jam. The product shall be of good quality with a palatable and appetizing taste. As per Food Safety and Standards Regulations, chutney\ shall contain a minimum of 40% fruit (w/w) in the final product with total soluble solids not less than 50%. The acidity in the final product shall not be more than 2% with ash content not exceeding 5%. However, for vegetablebased chutney as well as hot & sour (spicy) chutney, the TSS shall not be less than 25%. Recipe: The generalized recipe for the preparation of chutney from different fruits is as under:

Fruit syrup is a beverage that contains at least 25% fruit juice/pulp, 65% total  soluble solids and acidity ranging between 1.2 -1.5%. It is preserved by using 350 ppm SO2 or 600 ppm benzoic acid. Fruit syrup is diluted before serving. Syrup can be made from the juice/pulp of jamun, ginger, lemon, phalsa, rose extract, bael, pomegranate, and brahmi (Bacopa monnieri) leaves/root extract, etc. Besides, a syrup/sharbat containing a minimum of 10 per cent of dry fruits is also regarded as fruit syrup. Recipe: The generalized recipe for the preparation of syrups from different fruits is as under:

Preserve (Murabba) is made by cooking the fruit either whole or in slices/ pieces in sugar syrup of heavy concentration (65-70oBrix). Usually for 1 kg fruit around 1.75 kg sugar is used and the cooking is continued till the TSS reaches 68oB. Fruits like petha (ash gourd), aonla, bael, apple, pear, karonda, pineapple and papaya etc., are used for making preserve/murabba. Candies are also prepared similarly but the TSS is maintained up to 75-80%. For candy preparation, the fruit pieces are dipped initially in 55-60% sugar solution and the TSS of the syrup is increased by 5% everyday up to 4-5 days and then the fruit slices are drained free of syrup and dried in driers. Fruits like aonla, karonda, cherry, apple, ginger peels of orange, lemon, and grapefruit etc., and petha (ash gourd), are used for candy preparation. Selection and preparation of fruits: Wash the fruits in water to remove dirt and residues. Peel, core and cut the fruits into pieces. Pricking should be done with stainless steel forks. In case of petha (ash gourd), after pricking place them in lime water

Tomato, apple, plum, mushroom, etc., are used successfully for the preparation of sauces. Sauces are of two kinds 1) thin sauces consisting of vinegar extracts of flavoring material like herbs or spices and 2) thick sauces which are highly viscous. Sauces are prepared by maceration of spices, herbs, fruits, and vegetables in cold vinegar or by boiling. Thickening agents like pectin, carboxymethylcellulose,n etc., are also added to sauces to prevent the sedimentation of solid particles. The sauce is generally cooked to such a consistency that it can be freely poured without fruit tissues. Procedure Tomato fruits are washed, cut into pieces, and heated/boiled for about 10 minutes in their own juice in SS pan to soften the tissue. The heated fruit mass is passed through a pulper to separate skin and seeds. Half of the sugar and spices are placed in a muslin cloth bag which is then immersed in the pulp during cooking. Cooking is continued till the pulp is reduced to half of the original volume.

Drying and dehydration are interrelated terms. Drying generally refers to the method of removal of moisture from the food under natural conditions such as sunlight and wind for example open sun drying, shade drying etc. Whereas, dehydration refers to a process of removal of moisture by application of artificial heat under controlled conditions of temperature and airflow. In this case single layer of fruit and vegetables, either whole or sliced after primary pretreatments is spread on trays which are placed inside the dehydrator or in the open sun for drying. In the dehydrator, the initial temperature is generally kept at 43oC which is then gradually increased to 66-71oC for fruits and 60- 66oC for vegetables. Dried grapes (raisins and monucca), apricots, dates, apple rings/cubes, Morchella (Guchhi), bael, aonla, fig, green peas, cauliflower, cabbage, onion, garlic etc are commercial products prepared by using drying. Procedure for drying: Drying generally involves three stages: pre-drying treatments or pre-treatments, drying of commodity and post-drying operations such as handling, packaging and storage. The flow sheet for drying of fruit and vegetables is shown in Figure 1 and details of pretreatments for drying fruits and vegetables are shown in Table 1&2 respectively.

A cut-out examination is conducted for the evaluation of canned fruit and vegetables and other products for various quality attributes, viz., physical, chemical, sensory, and microbiological attributes. The examination is conducted by following the undermentioned steps: External/physical examination of unopened Can 1. External Appearance of the tin can: Note the external condition of the tin can like dents, rusty spots, scratches, leakage around seams, and the condition of ends. Based on external appearance describe the condition of the tin can by using the following terms: i. Flat Can: A can where both ends are concave. The vacuum is high enough to maintain the ends concave. ii. Flipper Can: A can where the vacuum is so low that mechanical shock will produce distortion of one or both ends. iii. Springer Can: A can in which one end is distorted and the other end is flat and pressure on the convex end will cause the flat end to spring out when pressed.