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The technique of preserving fruit by the use of low temperature dates from the eighteenth century with the first use of ice house in 1750. Later in 1800s commercial cold storages have come up for the storage of perishables like meat, dairy and fruit products.  The main change took place in the cold store in recent years has been the introduction of multi temperature chambers with humidity control for specific products. Cold preservation can be either refrigeration or freezing. Household refrigerators usually run at 4-7^ºC. Chilling or cold storage usually uses a slightly lower temperature on the basis of the food to be refrigerated. In freezing a temperature of -18^ºC or below is used. Chilling will preserve perishable foods for days or weeks and freezing will preserve foods for months or even years.

Drying is the oldest known method of preserving food. Drying or dehydration is removal of majority of water contained in fruit or vegetable. Although preservation is the primary reason for dehydration, it also lowers cost of packaging, storing and transportation by reducing both weight and volume of final product. In addition, dried foods add variety to our diets. In the process of drying, sufficient moisture is removed to protect product  from  spoilage. Processing should be done in such a way that food value, natural flavour and characteristic cooking quality of fresh material are retained after drying.

Processing of fruits  and vegetables into various products which could be preserved for a long time and add to value of product using proper cost effective technology will be a viable tool for improving   economic status of  farmer as well as our country. Modern methods of fruit and vegetable preservation are  broadly classified as follows:

Storage is one of the most important aspects of post harvest handling of fruits and vegetables. The main objective of storage is to extend storage life of fruits and vegetables and increase their period of availability. A substantial quantity of fruits go waste in India due to lack of proper storage facilities. Storage of fruits and vegetables is practiced for various reasons. Proper post harvest handling of fresh horticultural produce helps in extending  period of availability of wide range of  fruits and vegetables round the year, prevention of seasonal market gluts, orderly marketing, better return to grower and  preservation of  nutritional qualities. The   long  term  storage  of  fruits  and  vegetables is expensive and requires high level of technical  knowledge of crop. However, an orderly marketing reduces storage period considerably. 

Various systems were developed to take produce from field to consumer and selection of a particular method depends on several factors, including perishability and value of crop.  One method is to harvest the crop and take it to a packhouse for various unit operations like grading, cleaning, post-grading treatments, and packing for transport and marketing. When deciding upon where to locate a packinghouse, access to field and market point, adequate space for vehicles to enter and leave  packinghouse and ease of access to labor will all be considered.
 
In the simplest packinghouse, produce is delivered in picking containers, immediately after harvest, directly to packers.  Packers then sort, grade, size and pack the produce directly into appropriate transport containers. In this case, each worker must be aware of produce defects, grade and size requirements, and packing methods.

Maturity at harvest is the most important determinant of storage life and final fruit quality. Maturity indices are determined for many fruit, vegetable and floral crops. Harvesting crops at proper maturity allows handlers to begin their work with the best possible quality produce. Produce harvested too early may lack flavour and may not ripen properly, while produce harvested too late may be fibrous or over ripe.
 
Almost all fruits reach their best eating quality when allowed to ripen on the tree or plant (exceptions e.g., pears, avocados, and bananas). In general, fruits become sweeter, more colourful, and softer as they mature. A few fruits are usually picked mature but unripe so that they withstand post harvest handling system when shipped long distances.  Most of  currently used maturity evaluation is based on a compromise between those methods that would ensure the best eating quality and those that provide flexibility in transportation and marketing.  Optimum harvesting stage depends upon type of fruit or vegetable and their final use. Such a division is usually based on their classification according to physiology, environmental conditions, ripening bahaviour and nutritional aspect. Some of the classifications, important for their harvesting and storage are briefed in  subsequent sections.

Structure

Structural unit of edible portion of most fruits and vegetables is the parenchyma cells and makes up bulk of cells. A parenchyma cell is rather thin walled and may be polygonal or cubical in shape.  Walls of parenchyma cells in young plants are composed almost entirely of fibrils of cellulose. In parenchyma cells of plants actively metabolising protoplast portion represents only about 5% of total cell volume. This protoplast is rather film like and is pressed against cell wall by large water filled central vacuole.  Protoplast has inner and outer semi permeable membrane layers between which is confined cytoplasm and its nucleus. 

Fruits and vegetables are very important food commodities. India has become the largest producer of fruits and the second largest producer of vegetables. Though the production of fruits and vegetables make us believe in our strength for self-sufficiency, a significant qualitative and quantitative loss occur in the produce from harvest till consumption.  For self sufficiency and also for processing, export and to meet additional requirements, a lot of emphasis need to be given to reduce post harvest losses, besides increasing  production and productivity of horticultural produces. Processing plays an important role in  conservation and effective utilisation of these perishable commodities. However, only less than 2% of total production of fruits and vegetables are processed.  The new industrial policy has placed this sector in the list of high priority areas.

6.1 Strength of India
    ·    In India, pomegranate is cultivated over 1.31 lakh ha with a production of 13.46 lakh tonnes and a productivity of 10.27 t/ha. 
    ·    India is the largest producer of pomegranates in the world.
    ·    Pomegranate is currently ranked 10th in terms of fruit consumed annually in the world. India is the only country in the world where pomegranate is available throughout the year i.e. From January to December. It is cultivated in 3 seasons (Ambia bahar, Mrig bahar and hasth bahar) in Deccan plateau of India. 
    ·    India is endowed with wide agro climatic conditions that offer immense scope for cultivation of various kinds of fruit crops. This provides an excellent platform for the country to emerge as a leading producer of fruit crop. 

5.1 Present Status

Export of pomegranate has decreased in quantity from 36,027.43 tons in 2012-13 to 20,997.02 tons in 2014-15, whereas in value term it show an increase trend during the same period. There is tremendous potential for exports of pomegranate from India and it is fact that India is largest producer of pomegranates in the world. Moreover, India produces finest edible quality of pomegranates which are available almost throughout the year. The major Markets of India’s pomegranate during the year 2014-15 were UAE, Nepal, Saudi Arabia, Kuwait and Netherland.

4.1 Harvesting

Pomegranate being non-climacteric fruits should be picked when fully ripe. Its fruits become ready for picking 120-130 days after fruit set. Mature fruits should be immediately removed from the plants as delay in harvesting leads to fruit cracking. Fruits harvested at a premature stage have poor keeping quality and are prone to damage during handling and transport. The fruits are harvested when outer rind becomes yellowish and the fruit when tapped produces a metallic sound. The round fruits become flattened from all the sides and basal beak shaped portion shrinks at the time of maturity. Fruits are harvested with the help of secateurs by retaining 1 cm stalk with the fruit. All the fruits should be harvested in 2-3 pickings within a span of one month.

3.1 Integrated Insect Pests Management

1. Anar butterfly [Deudorix (Virachola) isocrates Fabricus]

Pomegranate fruit borer or pomegranate butterfly is the most widespread, polyphagous and destructive pest distributed all over India and common in Asia. Peak incidence is during the month of August in monsoon season, while it is more during November/December in winter crop. Infestation from flowering to button stage causing loss up to 50 per cent of the fruit. Adult bluish brown butterfly, female with V shaped patch on forewing. Full-grown larvae are dark brown with short hair and white patches all over the body and measures about 16 to 20mm long. The larvae bore into the pomegranate fruits soon after hatching. Once inside the fruit, larvae (approx 2cm length) feed on the flesh and seeds.  The bored hole is plugged by the last abdominal segment of the larva. When fully grown, the larva comes out by boring through the hard shell and spins a web, which ties the fruit, stalk to the main branch. Offensive smell and excreta of caterpillars coming out of the entry holes with excreta stuck around the holes. The fruits rot and drop off. The holes ultimately expose the rest of the fruit to disease, and typically rot off the tree.

2.1 Soil and Climate

Pomegranate grows well in sandy-loam and well-drained soils having a pH of 7.5. It can also be grown on light soils. Quality and colour development in light soils is good but poor in heavy soils. It tolerates salinity up to 9.00 EC/mm and sodicity 6.78 ESP. Even it can be grown well in slightly saline soils as it is considered a saline-tolerant plant (Patil and Waghmare 1983; Rao and Khandelwal 2001; Ram Asrey et al., 2002). Accumulation of salts, in excess of 0.5% of the soil mass causes dying off of growing roots. Interestingly, application of Paclobutrazol (250 ppm) was reported to reduce salinity damage (Saeed 2005). The presence of water-soluble salts like sulphates and chlorides and ex- changeable sodium negatively affect root formation.

1.1 Introduction

Pomegranate (Punica granatum L.) is a well-known table fruit of tropical and subtropical regions of the world. The Romans received it from Carthage, hence the name of the genus Punica. Some botanists place it in the family Lythraceae, of the peculiar type of fruit, called as balausta, most authorities make it the only genus in the family Punicaceae. It belongs to genera Punica and family Punicaceae (Chatterjee & Randhawa, 1952; Joshi, 1956). It is a small tree, measuring less than 4 m when cultivated, although it can reach 7 m in the wild. Recent research findings corroborate traditional use of pomegranate as a medical remedy as all parts of this plant have several bioactive metabolites (Holland et al. 2009). Consequently, its demand has increased tremendously not only in the western world but also in other parts of the globe.

INTRODUCTION

Food is the basic need of human beings. It gets spoiled primarily due to microorganisms and enzymes. Energy is required for microbial growth and enzymatic reactions. At low temperature, the rate of biochemical reactions is slow resulting in prolonged storage life of food. It must have been observed long back that food could be stored for longer period without deterioration during the winter months. Since then this principle is being used to extend the storage life of foods. A sea change can be observed in development of low temperature preservation technology. It has travelled a long journey to reach this stage; however, a major break through took place in twentieth century. Low temperature technology is of two types; refrigeration and freezing. In refrigeration storage, water is in liquid phase and temperature is maintained above freezing point. In freezing technology, the food is stored below freezing point and water gets converted into ice. The former is short term preservation due to slow growth of microbes and lower enzymatic activity while the later is long time preservation due to inactivation of enzymes during blanching and inhibition of microbial activity due to unavailability of free water and much lower temperature. Low temperature preservation is widely accepted and is of commercially important in food supply chain.

INTRODUCTION

Food being the basic need of all humans and other living organisms, the production and processing of food is a continuous activity with several new procedures and technologies adoption; thereby the quality of food needs an emphasis which also protects the consumers by providing safe and suitable food. The contaminated foods, food borne illness outbreaks though at times referred to poor consumer handling, commitment for provision of safe food to consumers is also a Governments concern. In the recent years, food safety measures through Food Safety programmes and increase in awareness are being followed. The food production in our country is the most promising sector which is the cause for white revolution and green revolution. India ranks first in the world in production of cereals and milk and second largest producers of fruits and vegetables. India stands second in inland fish production. It is second largest exporter of rice and so on. Food processing sector has a great potential which covers a wide spectrum of products encompassing agriculture, horticulture, plantation, animal husbandry and fisheries. But the growth of food processing industries in our country is rather slow. However, to encourage, the government is providing lot of incentives in the recent years.

INTRODUCTION

A food may have three attributes (1) Provide energy and nutrition (2) Give pleasure, i.e., enjoyable aroma, colour, and taste and (3) Health benefits. Functional food has physiological benefits and reduces the risk of chronic disease beyond basic nutrition.

Functional foods, also reported as ‘nutraceuticals’, ‘medical foods’ or ‘designer foods’ in the literature, were first described by Roberfroid (1999) as ‘Food similar in appearance to conventional food that is intended to be consumed as part of a normal diet, but has been modified to subserve physiological roles beyond the provision of simple nutrient requirements’. Examples are iodized salts, vitamin A and vitamin D fortified milk and yoghurt, folic acid enriched bread, soy products, wheat bran and oats products.

INTRODUCTION

Food processing as a technological regime is undergoing a revolutionary change in terms of conception, product and process design and energetics. The conventional approach of a food processor is to develop products with a long shelf-life in user friendly packaging systems. Food processors are usually bothered about sensory attributes and microbiological profiles without much emphasis on the fate of heat labile nutritional and nutraceutical components. The changing consumer perception is slowly but steadily leading towards emergence of novel technologies without depending upon conventional thermal processing. A few years before, non-thermal techniques have emerged for food processing and preservation, but these techniques were restricted to framing of fundamentals with regard to the inactivation of vegetative and reproductive bodies of microbes and the deteriorative enzymes.

INTRODUCTION

Packaging is an important aspect in modern life and in fact the word ‘packaging’ developed a literal value indicating presentation of an issue or material in a comprehensive and compact manner. Food packaging has become a revolutionary trend and plays a dominant role in the promotion of marketing of various fresh and processed food products. The reason could be a number of aspects inclusive of protective, legal and aesthetic elements. The industrial revolution in the late 18th century caused major impact on manufacturing process. Without appropriate packaging no food is acceptable and even in the common household food packaging is being practiced in its own way to render food safety and convenience for various culinary operations. Therefore, food packaging needs to be considered as an essential element of food processing and marketing and it is one of the key areas in food technology making rapid strides in research and development.

INTRODUCTION

For thousands of years fermentation processes were largely natural phenomena exclusively identified with food preservation throughout the world. Fermentations can play a significant role in meeting the ever growing food requirements of world population providing benefits in the form of innovative food products with improved nutritional value and food quality along side better safety. Fermentations can be used to address a large variety of food related problems and in the development of processes to meet the demand for food. In the wake of estimations made by international organizations that global food demand and population would increase by two-fold by the year 2050, much emphasis has been placed over the ways and means to increase food production and preservation.