eChapters

1. Introduction

Now a days, foods are not intended to only satisfy hunger and to provide necessary nutrients but also to prevent nutrition-related diseases and improve physical and mental well-being of the consumers (Menrad, 2003). In this regard, functional foods play an important role. The concept of functional foods which has evolved as the role of food in the maintenance of health and well-being and in the prevention of disease, has received increased scientific and commercial interest is recent past. Growth of functional foods markets include increased consumer health awareness, increased popularity of healthy foods, search for food-based drug substitutes, self-medication approach promoted by busy lifestyles and rapidly developing health conscious markets. Functional foods can be defined as foods “that can beneficially affect one or more target functions in the body, beyond adequate nutritional effect, in a way relevant to an improved state of health and wellbeing and/or reduction of risk of disease” (Stanton et al., 2005).

1. Introduction

Milk and milk products constitute essential dietary components for a vast majority of the population. India with annual production of more than 135.6 million tonnes has emerged as leading milk producing nation. The per capita per day availability of milk in India is more than 290 g. Buffalo milk accounts for 57% of the total milk produced in India. Ethnic dairy products account for 90% of all dairy products consumed (Aneja et al., 2002). Many health benefits have been attributed to fermented dairy products and probiotic microorganisms (Salminen et al., 1998). The market for functional foods, nutraceuticals, wellness foods and beverages is fast growing. The harmful effects of synthetic drinks have propelled health conscious consumers to go for natural and traditional drinks. In search of better returns, the Indian dairy industry is widening its focus to include traditional milk products, and these are emerging as new profit centres for the organised sector.

Traditional dairy products have several advantages. They require low capital investment and give high profit margin. They are more appealing to the Indian palate. Dahi or curd is the most popular indigenous fermented dairy product. There are numerous references to dahi in vedic literature. The Prevention of Food Adulteration Act (Anon, 1976) describes dahi as a product obtained from pasteurized or boiled milk by souring (natural or otherwise), using harmless lactic acid or other bacterial cultures. Indian dahi and its western counterpart yoghurt differ considerably in terms of cultures used and their bouquet and flavour profiles (Aneja et al., 2002). The major flavor compound in dahi is diacetyl. Dahi made from buffalo milk has a firm body and white glossy appearance, with a cream layer on top. Mixed mesophilic cultures of Lactococcus lactis subsp. lactis, Lactococcus lactis subsp. cremoris, Lactococcus lactis subsp diacetylactis along with Leuconostoc species are grown together for production of dahi.

1. Introduction

Fermented milk products such as yoghurt are produced through out world (Kurmann et al., 1992). Yoghurt can be characterized as a gel like coagulated milk product, having a smooth consistency and a pleasing flavour and is now widely consumed both by infant and adult populations. It is common that yogurt preparation involves the use of equal amounts of two lactic acid bacteria (LAB): Streptococcus thermophillus (St) and Lactobacillus delbrueckii ssp. bulgaricus (Lb); samples prepared with these starter bacteria are labeled Lb-St (Ng et al., 2011). In the early stage of the incubation process, Lb stimulates the growth of St releasing amino acids from casein (where the most important is valine) and producing a moderate reduction in pH due essentially to St. Yoghurt has better digestibility than milk and this is related to its comparatively high content of free amino acids. Besides nutritional value, it possesses hypocholesterolaemic (Mann, 1977) and antitumour effects (Odd et al., 1983; Reddy et al., 1983).Yoghurt may be set or stirred and has a potential for being used as dietary supplement for infants. So they cross the line between dietary supplements, health foods and conventional foods with great facility. Now a days, emphasis is given on sweeteners and more natural sweeteners will be used (Hollingsworth, 2001). Natural sweeteners can be easily incorporated in yoghurt by blending cattle milk with fruit pulps like mango. The enhancement of other nutrients e. g. vitamins and minerals will be added advantage. Mango pulp which contains a high proportion of sugar, mostly monosaccharide, is easily adsorbed by the digestive systems (Celik and Bakirci, 2003).

Soybean is a comparatively inexpensive source of high quality protein. The protein and fat contents in soybean are above 40 % and 20 %, respectively. Nutritionally, soy protein is a more balanced plant protein for human consumption. Studies have indicated that consumption of soy protein decreases total serum cholesterol and minimizes risks for several cancers (Anderson et al., 1995; Messina, 1997; Zind, 1998). The positive health benefits associated with soybeans have greatly increased its consumer awareness which has created a large market for soy foods (Ohr, 2000; Liu, 2000). The problem of beany flavour in soy products can be overcome by lactic acid fermentation (Buono et al., 1990; Granata and Morr, 1996). Soy solids are not only abandoned source of protein but also have therapeutic properties against breast, prostate, colon and lung cancers due to its isoflavones like genistein and daidzein content. Fortification with soy made yoghurt beneficial in lowering cholesterol level and blood pressure and in relieving symptoms of menopause and osteoporosis.

1. Introduction

Extrusion is one of the most preferred ways for creating the indulgence called ready-to-eat (RTE) snack foods with diverse shapes, sizes, colours and also nutritional and functional values which appeal to the diverse group of consumer with varied choices. In this chapter ready-to-eat extruded and puffed snacks are the focus covering the technology involved, criteria for ingredient selection, design of experiment, process modelling, effects of extrusion on physical, nutritional and functional quality of the snack; a few relevant case studies are also discussed.

1.1 Market for RTE snack foods

Indian cooking and lifestyle have undergone tremendous changes in the last 15 years. There are many major factors impacting this change which include, liberalization policy, dual income, separate living of couples, innovative kitchen applications, media proliferation, etc. The cooking style and eating habits in India varies drastically from southern part to northern part of the contry. Due to lifestyle pressure nowadays people prefer easy short way of cooking food rather spending too much time on cooking. Rapid urbanisation is also one of the reasons for people to buy such products. Snack foods comprise a very large variety of items including potato chips, crackers, nuts and extruded snacks, among others (Harper, 1981). Snack food extrusion includes subjecting selected raw material to a variety of complex physical processes to yield snacks with varied shapes and textures (White, 1994).

The RTE market in India was expected to expand to reach Rs. 2,900 crore by 2015, according to an analysis done by Tata Strategic Management Group (TSMG). The products may vary from noodles, pasta, masala packages, stuffed paratha, etc. and many more. There are many regional players who are making foray into ready-to-eat segment. Many national and international players like Nestle, Pepsico, ITC, Haldirams, Cavinkare, are already in Indian market with their products.

1. Introduction

1.1 Malnutrition

The term malnutrition generally refers both to under nutrition and over nutrition, but in this guide we use the term to refer solely to a deficiency of nutrition. Many factors can cause malnutrition, most of which relate to poor diet or severe and repeated infections, particularly in underprivileged populations. Inadequate diet and disease, in turn, are closely linked to the general standard of living, the environmental conditions, and whether a population is able to meet its basic needs such as food, housing and health care. Malnutrition is thus a health outcome as well as a risk factor for disease and exacerbated malnutrition, and it can increase the risk both of morbidity and mortality (Ogunrinade, 2014). A term used to refer to any condition in which the body does not receive enough nutrients for proper function. A person cannot properly digest or absorb nutrients from the food they consume, as may occur with certain medical conditions (Medicine, 2015). Malnutrition may range from mild to severe and life-threatening. It can be a result of starvation, in which a person has an inadequate intake of calories, or it may be related to a deficiency of one particular nutrient (for example, vitamin C deficiency).

Malnutrition is estimated to contribute to more than one third of all child deaths, although it is rarely listed as the direct cause. Lack of access to highly nutritious foods, especially in the present context of rising food prices, is a common cause of malnutrition. Poor feeding practices, such as inadequate breast feeding, offering the wrong foods, and not ensuring that the child gets enough nutritious food, contributes to malnutrition (WHO, 2015).

Pooled estimates report the prevalence of malnutrition among community-dwelling older adults of 6% and among hospitalized older adults of 39%. In developed countries, treatment of malnutrition is relatively inexpensive and effective: energy and protein supplementation using commercial “sip feeds” results in both weight gain and reduced mortality (Pereira et al., 2015). In 2013, one in four children under age five worldwide had stunted growth. Between 2000 and 2013, stunting prevalence globally declined from 33 to 25 %, and the number of children affected fell from 199 million to 161 million. In 2013, about half of all stunted children lived in Asia and over one third in Africa (UNICEF, 2015). Malnutrition may be several types as follows:

1. Introduction

1.1 Engineered health rice

Rice is one of the leading food crops in the world and sustains two-third of the world’s population providing 20% of the world’s dietary energy supply. It can be polished and marketed as white rice or can be marketed with the bran layer left intact as brown rice. The dry grain can then be steamed or boiled by the consumer to rehydrate and cook it (Kato, 2006). Despite its primary importance as a staple food, rice has several disadvantages. Primarily, rice is low in protein and high in starch. The low protein levels in rice can lead to protein malnutrition in societies where rice is the primary constituent of the diet. Deficiencies in essential amino acids may also result from a diet primarily comprised of rice. For example, lysine is the essential amino acid found in the lowest quantity in rice. The human body needs lysine for proper growth and repair of tissues. It is also important in the production of various enzymes, hormones and disease-fighting antibodies (Kato, 2006). The production of broken rice is nearly 15-20% of total production of rice (Bhullar and Bhullar, 2013). The broken rice is generally used for rice flour production and Indian traditional foods such as Idli, Dosa and weaning foods etc. Ugwu et al., (2012) reported that the rice broken can be utilized for the production of poly (3-hydroxybutyrate). The major value addition of broken rice is possible by reconstructing it into rice-shape and fortifying it with desired nutrients or micronutrients, which is a big challenge in terms of making the product acceptable to the consumers.

One approach to overcome the above mentioned challenges is to prepare artificial rice kernels or rice analogues by extrusion, in which the vitamins are embedded and consequently do not separate from the rice grains. This will utilize mainly the broken rice which is either discarded or sold at subsidized prices as the cattle feed. Furthermore, embedding makes extraction of the vitamin by rinsing or cooking more difficult and may provide a certain protection against oxidation, because the vitamins can be enveloped by a protective matrix (Steiger, 2010). The fortification of commercially produced staple foods allows exposed populations to benefit without making major changes to their eating habits (Kunz, 2009).The rice analogues prepared from extrusion can be used by addition of an appropriate proportion of water at a temperature ranging from 90°C-100°C, whereupon the rice product rehydrates within three minutes to obtain a product having the desired appearance and organoleptic properties to simulate natural rice grains (Harrow and Martin, 1982).

1. Introduction

Celiac disease (CD) is an immune-mediated enteropathy triggered by the ingestion of gluten in genetically susceptible individuals. Gluten is the protein component in wheat, rye and barley. In the last 10 years, cutting edge scientific developments in this disease have led to the formulation of new concepts of epidemiology, pathophysiology and clinical manifestations. At present, the only available treatment for CD is a strict gluten-free diet (GFD) (Mulder et al., 2013; Theethira and Kelly, 2014). Until recently, the geographical distribution of CD was mostly restricted to Europe and other developed countries, such as the United States, Canada and Australia. Celiac disease is not only frequent in developed countries, but it is increasingly found in areas of the developing world, such as North Africa (Malekzadeh et al., 2005), Middle East (Rostami et al., 2004) and India (Basu et al., 2014, Deora et al., 2014; Yachha and Poddar, 2007). New epidemiological studies have brought evidence that this disorder is common in many developing countries as well, showing that the ‘global village of celiac disease’ has indeed a worldwide distribution (Fasano and Catassi, 2001).

The only available treatment for celiac disease is the strict, lifelong avoidance of gluten. When gluten is removed from the diet, the small intestine will start to heal and overall health should improve (Fasano and Catassi, 2001). Traditional substitutes for gluten-containing grains have been rice, tapioca, corn, and potato. However, more nutrient-dense grains, seeds, nut flours, and legumes are being incorporated into the diet to provide an enhanced palatability, variety, and nutritional quality. These include sorghum, millet, teff, quinoa, amaranth, flax seed, and buckwheat.

1. Introduction

The development of food products using composite flour has increased and is attracting much attention from researchers, especially in the production of bakery products and pastries. This article focuses on the use of composite flour to produce food products, namely bread, biscuits, and pasta, with looks at on its impact, following some improvements made, on the sensory quality, rheology characteristics, and nutritional values as well as its overall acceptance. The blending of wheat flour with various sources of tubers, legumes, cereals and fruit flour in different percentages to produce variety of food products are also reported. The positive effects of the use of composite flour can be seen in the final product related to the functional and physicochemical properties and health benefits of raw blended flour along with percentage blending. Overall, composite flour is a good new approach to utilizing uncommon food products as the application of composite flour produced products with different characteristics and quality, depending on the types and percentage of wheat flour used in the formulation.

Bread has been the staple food worldwide and habit of bread is derived in part due to the convenience and wholesomeness. Wheat is a commonly used cereal for making bread as it gives the desired texture due to the presence of gluten forming proteins like gliadins and glutenins (Decock & Cappelle, 2005). In earlier times idea of composite flour in developing countries originated in order to cut down on import of wheat (as it was not grown in many countries) but in recent past refined wheat flour consumption has lead to health issues and thus in order to improve nutritional and functional properties composite flour has been the norm. Composite flour is the one obtained by mixing wheat flour with cereal and legume flours for making bread and biscuits (Dendy, 1992). However, mixing of non-wheat flours, roots and tubers, legumes or other raw materials can also be regarded as composite flour.

1. Introduction

As dealt in earlier chapters, fruits and vegetables represent the most essential of horticultural component for acreage of production, yield, nutritional and nutraceutical values, of definite taste, texture, flavor and colour, involving defined health and medicinal benefits. Every year and over the course of every ten years, significant quantum of research data accumulates on the various facets of fruit and vegetable technologies, and also trends in production, processing and marketing, may also tend to change. At every stage, more thinking has gone to improve the technology, product quality and cost economics to suit wider markets, both domestic and foreign. It is a continuous endeavor to record newer and newer problems emerging and to set the strategies to solve them. Several relevant references, fitting to the various aspects representing the cross section of the fruit and vegetable technologies are dealt here, to conclude the subject and spell out the future.
Consumer demand for healthy convenience meals with ‘near fresh’ properties challenges researchers and industry to develop new or improved conservation procedures for processed products. Development of a dehydration process based on electromagnetic energy (EME) may bring about a major breakthrough with respect to retention of product quality and improved rehydration characteristics (Nijhuis et. al., 1996). Economic potential and current limitations of fruit and vegetable processing in India included improvements in preliminary treatment (harvesting, washing/cooling) precooling (including refrigerated transport/storage) and processing of juices and pulps. Establishment of a National Horticulture Board has aided to provide market information and so aid growers to get remunerative prices (Anon, 1993). The use of food irradiation as a quarantine method for treatment of food and agriculture commodities was organized by the joint Food and Agriculture Organization/International Atomic Energy Agency Division of Nuclear Techniques in Food and Agriculture, held in Kuala Lumpur, Malaysia, on 27-31 Aug., 1990. (FAO,1992). This has been experimented with various commodities, particularly for export trade of fruits like mango, as stipulated by the importing country like U.S.A.

1. Introduction

 Banana is the developing world’s fourth most important food crop (after rice, wheat and maize) accounting for 70 million metric tons per annum (FAO stat, 2007 faostat.fao.org/site/567/Desktop Default.aspx?). Banana is also the second highest fruit crop in the world, representing a wide range of varieties of cooking and dessert types, providing a staple, nutritious inexpensive food for millions of people. The word “banana” is a general term embracing a number of species or hybrids in the genus Musa of the family Musaceae known simply as the banana family. Two Musa species namely Musa acuminata and Musa balbisiana, out of the 28 described were first noted in 1865 by Kurz as being the origin of most of the commercial clones (Stover and Simmonds 1987). Cultivated clones are parthenocarpic, mostly sterile with starchy fruits. Indeed, wild types are very fertile; their fruits are full of seeds with little starch, and are seldom fit for human consumption. Its abundance, varietal diversity, availability round-the-year and low cost make banana an important commodity for the religious occasions in many tropical countries. The vegetable bananas, generally grouped under ‘Plantains’ are larger, more angular than dessert type and are generally intended for cooking unripe, although ripened ones are quite like dissert bananas.

1. Introduction

Mushrooms represent a highly specialized group of fungi, mostly basidiomycetes, with production of fruiting bodies bearing the spores for continued propogation. The fruiting bodies vary greatly in shape, size, color, texture, structure and aroma (Rajarathnam et al., 1998). They are endowed with the unique ability to biodegrade cellulosic wastes, including lignin, and biotransform into edible fruiting bodies (Rajarathnam et al., 1992, 1998, Rajarathnam and Zakia Bano, 1990). Their chemistry is also varied comprising characteristic polysaccharides, phenolics, proteins, amino acids, peptides, lectins, fatty acids, minerals, and so on (Rajarathnam et al., 1998). The wide spectrum of compounds have endowed the mushroom species with a spectrum of biofunctional activities of medicinal importance and accordingly their role in human health are implicated through studies on chemical, cell culture and animal feeding experiments. Vast literature available on this subject is condensed for presentation here.
Fifty nine medicinal species are reported from Diaoluoshan Nature Reserve in Hainan Province, China (Li et al., 2003). A health food made from luminescent mushrooms (Mycena chlorophos) is described. The luminescent parts that emit light in the carpophore of the mushrooms are dried without thermal decomposition and pulverized (Sugimoto, 2006). Consideration is given to the health promoting properties of 3 types of Asian fungi, namely, shiitake (Lentinus edodes), reishi (Ganoderma lucidum) and maitake (Grifola frondosa). Properties considered include beneficial components (e.g polysaccharides, vitamins, amino acids) and effects on the immune system (Anon, 1997). Auricularia auricula (kikurage or tree-ear) and Tremella fuciformis (shirokikurage or white jelly-leaf) are widely used in Chinese cuisine. Chemical structures of some of the polysaccharides from A. auricula and T. fuciformis, in relation to their medicinal and nutritional effects are described (Misaki and Kakuta, 1995).

1. Introduction

The chemical composition of a food is of utmost importance from many standpoints, including nutrition, safety, and stability to microbiological, chemical or physical changes. Analysis of these food components is required to provide nutrition labelling for informing the health-conscious consumer, for quality assurance during processing and storage, and for regulatory purposes. The methodology used in analysis will depend on the particular component and the nature of product being analyzed, the purpose of the analysis, and the availability of resources. The emphasis of this chapter is on understanding the principles, procedures and calculations involved in estimating a particular component in fruits, vegetables and their products.

1. Introduction

Fruits and vegetables have been an integral part of man’s diet from immemorial times. Fruits are the portions of plants that bear seeds, while vegetables are the edible components of a plant, including the leaves, stalks, roots, tubers, bulbs, flowers and seeds. These can be eaten raw or cooked. Fruits and vegetables can be preserved for short-term intervals under refrigeration, with or without receiving a minimal treatment like slicing, chopping, shredding or peeling. Fresh produce may also be irradiated or packaged in controlled or modified atmosphere in films for short-term storage. Long-term preservation includes canning, juicing, drying and addition of preservatives. Food contamination with hazardous biological agents remains a worldwide challenge in food safety and nutrition (Kenny 2002; Schlundt 2002; Tauxe et al 1997). Microorganisms form part of the epiphytic flora of fruits and vegetables and many will be present at the time of consumption. Production practices, growth conditions and the location of the edible part during growth (soil, soil surface, aerial part) will in combination with intrinsic, extrinsic, harvesting and processing factors affect their microbial status at the time of consumption. Man-made sources may be directly from farm laborers and from the equipment used for harvesting or storage. The types of microorganisms on fruits and vegetables would also vary with the orchards, vineyards or growing fields. The resident microflora normally subsists on the slight traces of carbohydrates, proteins and inorganic salts that dissolve in the water exuding from or condensing on the epidermis of the host. The numbers of bacteria present will vary depending on seasonal and climatic variation and may range from 104 to 108 per gram. The inner tissues of fruits and vegetables are usually regarded as sterile (Lund 1992). However bacteria can be present in low numbers in the insides of the fruits and vegetables as a result of the uptake of water through certain irrigation or washing procedures.

From the earliest time, man had to conserve and preserve his food, so that surplus at harvest following a successful crop can be stored for use throughout the year. Prime agricultural products in general and more so with fruits and vegetables which are being processed world wide or preserved to a more stable form so that they can withstand transport, handling and storage over a long period. As civilization developed, man learnt to preserve fruit and vegetable products with salt, spices and by drying , smoking or cooling which could extend their shelf life. Later by experience, he learnt that by protecting it from environmental factors such as air, moisture and light, the shelf life of these processed products could be further increased. He tried to keep them dry and covered to protect from insects and rodents. As with solid foods, primitive man experimented with beverages also. It is likely that the first beverage known to him after water was fruit juice. This undoubtedly led to the discovery of wines made from the fermented fruit juices. Later on, preservation methods and development of packaging materials underwent drastic changes.

1. Introduction

Processed foods have become a way of life in the modern world. Manipulation of chemical and physical properties facilitated by modern food technology and followed by addition of food additives has created a plethora of innovative food products that offer consumers greater convenience, variety, safety, satiety and quality.
Food additives have been in use for centuries for preservation, for providing improved appearance or desired texture and flavour. Preservation of foods started with salting and smoking. The Egyptians used colours and flavours, Romans used saltpeter and in India, turmeric is being used. Similarly additives such as baking powder as a raising agent, thickeners for sauces and gravies and colours- synthetic as well as from natural sources are being used.
Today more than 2500 food additives have been in use mainly due to the spurt in the research activities in food science and technology that are aimed at providing different characteristic functions to foods. Out of these, about 1300 are the flavouring additives.

1. Introduction

Fruits and vegetables in fresh form in general contain very high water content, with the fast rate of metabolic activity, including respiration rate, which may vary with the fruit type. Accordingly, the storage life at room temperature is considerably less, to expect acceptable quality. A range of transformational changes occur in various features of the fruits and vegetables, such as color, flavor, texture, structure, sweetness, sourness, pungency, astringency and so on. Phenolic browning of mushrooms, intensive softening of papaya, coloration and softening of ripe banana, softening of pear and jackfruit , flavor transformations of mango, banana and jackfruit after ripening, their color and texture transformations, are classic examples of post-harvest changes in fresh commodities, over a course of storage period at room temperature. These physical and sensorial perceptions of fresh commodities over a length of storage period are based on the range and multitude of operations of physical, chemical and bio-chemical reactions occurring in various constituents of the fresh fruit or vegetable such as moisture, pigments, vitamins, pectin, cellulose, hemicelluloses, phenolics, lignin, sugars, flavor compounds, amino acids, fatty acids and so on. In order to increase the storage stability, the fresh fruits and vegetables are processed and converted into various products such as juice, RTS beverages, jam, jelly, marmalade, fruit spread, dehydrated, spray dried powder, frozen stored, fruit cereal flakes, canned, candied, fruit bar and so on. Based on the nature of processing, the original form, shape, size, texture and structure are transformed, however with due maintenance in storage acceptability. A number of external factors are applied to achieve this product range such as heat, air velocity, pressure, radiation, chilling, freezing, vacuum impregnation etc. The ultimate quality of the final product is essentially an interaction between and amongst the various chemical constituents so characteristic of each fruit or vegetable under study, and a sum total of positive and negative reactions related to sensorial acceptability of the product. This quality is again a function of the storage period and the conditions of storage. Consumers in modern days are more health conscious to choose between consumption of fresh or processed fruits and vegetables. For trade over distance and time and particularly for geographic regions not producing a particular fruit or vegetable, it is of utmost importance to process the fresh produce. Enzymatic transformations in color, texture and flavor deserve utmost attention to ensure acceptable quality of the processed product, in particular over the course of storage period or until consumed after transportation and marketing. Microbiological quality of the product in final form is a most vital factor of consumers' health and this is dependent on water activity, sugars and protein / amino acid contents. In this regard, additives and preservatives come into picture. Strict regulations are imposed on their use, type and concentration over a storage period, for healthy consumption. Accordingly, this chapter would deal with several examples of processing conditions influencing the quality of the product, that emanates. Processing involving chemical, bio-chemical, engineering, bio-technological and microbiological methods to achieve a product are vivid, varied and different to different species / variety of fruits or vegetables to target different products.

1. Introduction

 Mushrooms have been part of man’s diet for centuries (Rajarathnam and Shashirekha, 2003). Mushrooms grow on wide range of agro-residues, biodegrade and biotransform them into edible fruiting bodies (Rajarathnam and Zakia Bano, 1988a; 1988b; 1990; Zakia Bano and Rajarathnam, 1988; Zakia Bano et al., 1993; Rajarathnam et al., 1998). Their post-harvest life is very ephemeral at room temperature (Rajarathnam et al., 1983) due to delicate flavor (Rajarathnam et al., 1990) and high moisture content, with a range of chemical constituents (Zakia Bano and Rajarathnam, 1986; 1982; 1988; Rajarathnam and Zakia Bano, 1990; Rajarathnam et al., 1983; 1992). Since, they contain large quantities of water and therefore suffer considerable weight loss during transportation and storage, causes serious economic losses, due to reductions in weight and quality (Gray, 1970). When the supply of water, organic substances and minerals are cut off at harvest, the fresh mushroom enters a deterioration or perishable phase. Cap opening and stem elongation are the usual symptoms of senescence constituting visible evidence of deterioration. At room temperature, the shelf-life of mushrooms cannot be for more than 24 h (Rajarathnam et al., 1983). During this period, there are considerable changes in color, texture and taste. In addition, water is continuously being lost as a result of transpiration and respiration. Additional loss occurs from surface cracks and bruises that develop during growth and handling (Salunkhe et al, 1991). Fresh mushrooms are white or light buff, with no dark marks on either the cap or stem. The veil is closed and the gills are not visible. The upper surface of the caps should be strongly convex and stems should be plump rather than elongated. Mushrooms are grown on compost, usually in mushroom houses where the temperature and humidity can be controlled. Eventually after harvest, the mushrooms can never be able to withstand any increase in temperature and decrease in relative humidity. Mushrooms are commercially preferred at the immature stage characterized by closed caps, invisible lamellae, round stipe and light color. Agaricus development is classified into various stages (Table 1). Thus, the concept of physiology of fresh mushrooms being very complicated, bears a great impact on the delicate problem of extending the storage life. The various means and methods studied and adopted by various researchers to aim at extended storage life of fresh produce, underlined by its physical, chemical and biochemical properties and also development of value added products are critically evaluated.

1. Introduction

Bamboo has historically been an integral part of human culture. Bamboo is a mystical plant representing symbol of strength, flexibility, tenacity, endurance and compromise. Throughout Asia, bamboo has for centuries been integral to religions, ceremonies, art, music and daily life. Bamboo provides numerous environmental benefits such as playing a critical role in the balance of oxygen/carbon dioxide in the atmosphere. Bamboo is the fastest growing canopy for the regreening of degraded areas and generates more oxygen than equivalent ultraviolet rays. It is an atmospheric and soil purifier. Its soil conservation properties create an effective watershed, stitching the soil together along fragile river banks, deforested areas, and in places prone to earthquakes and land slides. Its fast growing and high yield nature makes it a highly valued renewable resource. Its low cost and abundance call for its utilization to a full extent. 

1. Introduction

There is intense commercial interest in dehydrated fruit and vegetable products especially mango powder, banana powder, orange powder, papaya cereal flakes to powder, tomato juice powder and other vegetable powders, which are in great demand for soups, biscuit type cookies supplemented with fruit powders (Ana Maria et al. 2009; Sunita and Chauhan 2008), pizza mixes and sauces. Natural fruit and vegetable powders are gaining lot of popularity in recent years as they are very easy to handle after production, require minimum storage space and they are attractive. Tamarind powder is developed from tamarind fruit (Tamarindus indica) (Manjunath et al. 1991) and recently cashew apple and guava residues from fruit juice industry were successfully converted into fruit powders and used at different levels of wheat flour substitution for cookies formulation (Ana Maria et al.2009) and fruit puree like papaya can be mixed with cereal flour to prepare slurry and after gelatinization, the slurry can be useful for preparing drum dried flakes and powder (Sunita and Chauhan 2008). Tropical fruits are exotic in flavor but their juices and purees are seldom available in dehydrated powder (James, 1971). Citrus juice concentrates were produced during world war II in powdered form by using spray, drum, vacuum-puff, and freeze drying (USDA, 1962). The preservation of fruits and vegetables by dehydration offers a unique method, which may be considered as an alternative low cost preservation technique. A shift from fresh to more and more processed foods with significant value addition is bound to occur sooner or later considering the socio-economic changes taking place in the country and the rapid integration of Indian economy with global system. Most popular brands are found in the “ready to consume” food sector.

1. Introduction

Intermediate moisture foods are semi moist foods that have some of their water bound by glycerol, sorbitol, salt or certain organic acids, thus preventing the growth of many microorganisms (Stewart et al. 2001). It is now well recognized that fruits and vegetables are dehydrated to an intermediate moisture level (20-50%) (Stewart et al. 2001; Purvi et al. 2003). As the intermediate moisture products are characterized by a semi moist consistency so these foods have enough moisture content to permit easy chewing but low enough water content to prevent spoilage production of intermediate moisture foods is based on an increased scientific understanding of the chemical reactions involved in traditional food preservation methods (Purvi et al. 2003).
There will be better retention of original flavor and texture compared to fully dried products, with concomitant reduction in bulk, weight and cost of packaging, transportation and storage. Such intermediate moisture foods are more appropriate for developing countries in view of their minimal processing requirements, stability under ambient conditions, safety, convenience, ease of nutrient content adjustment, energy savings and low capital investment. They are also eminently more suited than dehydrated or canned foods for military rations (FAO, 2005).

1. Introduction

Pulpy and juicy fruits like orange, guava, banana, grape, mango, papaya, pears, apples and jackfruit can be converted into fruit products like squashes, juices, cordials and ready-to-serve (RTS) fruit beverages. These RTS fruit beverages are both refreshing and thirst quenching and have become very popular. Liquid fruits are the clarified juices prepared from these pulpy and juicy fruits. There is a demand for liquid fruits in the international market for various applications. The liquid fruits can be used as a natural alternative to synthetic beverages. They can be suitably concentrated or diluted, blended with other juices and also can be carbonated as fruit based soft drinks. Removals of pulpy material from the juices make them easier to preserve by pasteurization and are amenable to carbonation. Pulpy fruits can be successfully processed into liquid fruits (clarified juices) by using pectic enzymes. The emphasis of the fruit juice processing industry has, so far, been mainly on conventional clarification processes like enzymatic and chemical treatments followed by filtration using filter aids; and concentration by vacuum evaporation.

1. Introduction

In this era of genomics, proteomics and metabolomics the challenge in nutritional science is to clarify human nutrient requirements and design nutritional strategies to promote health and functional longevity. Our ancient Indian belief that ‘we are what we ate’ and our future health as individuals may well depend upon what we eat today. Plant-based dietary antioxidants are believed to have an important role in the maintenance of human health because our endogenous antioxidants provide insufficient protection against the constant and unavoidable challenge of reactive oxygen species (ROS). We have various endogenous defense chemicals but they are inadequate to prevent oxidative damage that makes human system prone to various degenerative diseases. Hence, it is necessary for increased intake of dietary nutraceuticals that may help maintain the balance between oxidants and antioxidants, slow age-related changes, and prevent onset of degenerative diseases.

1. Introduction

At present there is an increasing demand for colourants from natural sources. Since there is a possibility of banning of synthetic colours in view of their carcinogenic properties and already a reduction in number of permitted synthetic colours from 13 to 8 numbers in our legislation (PFA, 2005), the demand for natural colours is evident. In Japan and European countries because of the green movement, the demand for synthetic colours has been reduced. Synthetic colours in global market account for 400 million dollars. Despite processing limitations and higher costs, the global market for natural colours is estimated to be more than 939 million dollars (Espszezola, 1998). Color is recognized as a major factor affecting food acceptance. The consumer expects a specific food to possess a well defined colour and rejects any appreciable deviation from the normal. The change in colour during the preparation of food is a useful guide to quality control and is used by many food processors as the criterion for selecting raw materials. The characteristic colour of raw food is due to the natural pigments present in the plant and animal material. These can be enhanced in processed food products through the addition of food colourants. Addition of colour can make up for the colour losses during processing. Some of the major groups of colours are anthocyanins, carotenoids, betalains, chlorophylls, flavones and chalcones. Some of the plant sources of pigments are kokum, roscelle, chilli, marigold, beetroot, grapes and safflower. Sources of natural colours can be plants, animals or microbes. Fruits and vegetables form one of the main plant sources of pigments. Some of the plant materials rich in colours viz., alfalfa, marigold, safflower, strawberry, aronia fruits, grapes, red cherries have been exploited for pigment extraction and the results have shown positive effects. Some of the interesting features of the work carried out by researchers in this area are presented in the following sections.

1. Introduction

Pectin is a polysaccharide present in the middle lamella of plant cell walls. The firmness and structure of the plant tissue are attributed to the presence of pectin in the middle lamella. The insoluble form of pectin is called protopectin and the soluble form is called soluble pectin (Kertez, 1951). Protopectin is abundant in green fruits and contributes to hardness of cell, where as soluble pectin is responsible for viscous nature of juice and pulp. Conversion of protopectin to soluble pectin results in loosening of the bonds between the cells and softening of the fruit tissues. Protopectin is reported to be hydrolyzed to pectin by enzyme action during ripening. Protopectin on restricted hydrolysis yields pectin or pectinic acid. Braconnot (1825) discovered pectin as the gelatinous principle of fruits.

1. Introduction

Food is processed for its preservation, hygienization or value addition. To date, the food preservation technologies such as canning, dehydration, freezing, pasteurization and controlled atmosphere and modified atmosphere packaging have been the main processes employed to preserve foods, with the use of antimicrobials and microwaves also being employed more recently. In future, however, technologies such as exposure to ionizing radiation, high pressure processing, ohmic heating and pulsed electric field processing, could potentially be the new alternatives to the above food preservation technologies.

Irradiation of food involves the exposing of food, either in prepacked form or as such to controlled doses of ionizing radiation being generated either by electrically driven machines such as electron beam accelerators, x-rays or gamma rays produced by radioactive isotopes such as CS-137,CO-60, to achieve certain desirable objectives. The process of exposing a range of food stuffs to specific doses of ionizing radiation is being used to extend the shelf life of food stuffs, to improve their overall safety and quality by eliminating pathogenic bacteria, by reducing number of food spoilage organisms, to reduce the bacterial load on herbs and spices and thereby making them safe to incorporate into food stuffs, to inhibit sprouting in stored tuber and bulb crops such as potatoes, onions and garlic, to disinfest grains, grain products and tropical fruits to prevent damage to the commodity and to meet the quarantine regulations(Arun Sharma, 2004, Farkas, 2006).

1. Introduction

Vegetables and fruits are the next in demand for human consumption after rice and wheat, in all parts of the globe. Fresh fruits & vegetables and their value added products are increasing in popularity day by day almost in all the countries, because of their richness in dietary fibre, minerals & vitamin contents and for their medicinal properties. Maintaining agricultural produce quality and its evaluation are thus naturally important. Decisions concerning maturity and ripeness of fruits and vegetables are based mostly on visual inspections, which are subjective in nature. The quality of fruits and vegetables is mostly decided on the basis of size, shape, colour, gloss, flavour, firmness, texture, taste and freedom from external as well as internal defects. Internal quality factors such as maturity, sugar content, acidity, oil content and internal defects, however, are difficult to evaluate non-destructively. Methods are needed to better predict the internal quality of fruits and vegetables without their destruction. Recently, there has been an increasing interest in non-destructive methods of quality evaluation, and a considerable amount of effort is being made in this direction. But the real problem is how these methods are to be exploited practically on commercial scales and what are the constraints faced in implementing them.

1. Introduction

Fruits and vegetables represent highly perishable items of agriculture, mainly because of their high water content in fresh form. Their production, yield and management under agriculture is dealt essentially under horticulture. They abound in species and varieties in different geographic regions of the world, influenced by the agro-climatic conditions. Some are endemic and confined to certain geographic regions only. Accordingly, they may be tropical, sub-tropical or temperate, depending on their requirements of temperature for growth and yield.

Materials Required

Record book

Procedure

    1.    Follow the instructions given by the teacher and the factory representative.
    2.    Listen carefully to the explanations of the factory representative
    3.    Observe the functioning of various equipments
    4.    Ask queries wherever not understood properly.
    5.    Note down the observations in your record book  

Observations

    1.    Name and address of the factory or processing unit
    2.    Size of the Unit (Large, Small, Cottage, Home)
    3.    FPO Licence No.    
    4.    List of products manufactured    
    5.    Height of the processing plant    
    6.    Information regarding raw material store, finished product storage    
    7.    List of equipments installed in the factory
    8.    Water supply system     
    9.    Waste disposal system    
    10.    Hygiene in the surroundings    
    11.    Any other

Materials Required

Sensory scoring card, products, pen/ pencil for coding, plain water.

Procedure

    1.    Assign codes to the samples i.e. a, b, c, …… or 1, 2, 3, ….. etc.
    2.    Keep the coded samples randomly (eg. c, f, a, b, d, e) in a row for evaluation
    3.    Start the evaluation of samples one by one. 
    4.    Evaluator should rank the samples on the basis of intensity of a single sensory attribute according to his / her preference.
    5.    Compute the means on the basis of the evaluation of different evaluators (replications).
    6.    List the samples in increasing or decreasing order of preference.

Materials Required

Sensory scoring card, products, pen/pencil for coding, plain water.

Procedure

    1.    Take the given two samples
    2.    Make them three by duplicating/repeating either one of the two
    3.    Assign codes to the samples eg. AAB, ABA, ABB,  BAB etc.
    4.    Ask the evaluators to evaluate the samples for any differences between the 3 on the given Specimen Evaluation Card.
    5.    Find out how many of the evaluators have chosen the odd sample correctly (say it is 16 out of 20 evaluators).
    6.    Now find out the degree of difference in the samples indicated by the evaluators who correctly found the odd sample (Say it is much as per 3, moderate as per 8 and slight as per 5 out of the 16 correct evaluators.).
    7.    Find out how many of the correct evaluators preferred A sample and how many the B sample (say 11 preferred A sample and 5 B sample).
    8.    After going through Annexure II you may conclude that the two samples differed significantly from each other as 16 out of 20 evaluators found the odd sample correct. But, the preference was not significant as it should have been at least 13 out of 16 judges indicating same preference so as to make it significant. So, it may be concluded that the two samples differ significantly but both are acceptable.

Materials Required

Sensory scoring card, products, pen/ pencil for coding, plain water

Procedure

    1.    Assign codes to the samples i.e. a, b, c, …… or 1, 2, 3, ….. etc.
    2.    Keep the coded samples randomly (eg. c, f, a, b, d, e) in a row for evaluation
    3.    Start the evaluation of samples for various sensory attributes one by one. 
    4.    Evaluator should rinse his/ her mouth after each sample so as to avoid overlapping of taste, flavour etc.
    5.    Assign marks from 1-9 based on pleasurable and un pleasurable experiences.
    6.    Compute the means for a particular attribute on the basis of the evaluation of different evaluators (replications).
    7.    Find out the best sample on the basis of highest average scores obtained.

Materials Required

Soxhlet apparatus, petroleum ether, water bath, sample, grinder, weighing balance, filter paper, threads.

Procedure

    1.    Take the given sample and weigh it (A)
    2.    Dry the samples in an oven till there is no more weight loss and weight it (B)
    3.    Grind the sample into powder.
    4.    Place a weighed quantity of sample in filter paper, wrap the paper and tie it tightly with a thread so that no powder comes out of the paper during extraction. 
    5.    Pour approximately 100 ml of anhydrous ether into the bottom flask. Turn the heaters on. Set the temperature at about 40ºC.  
    6.    The ether will evaporate and circulate through the sample and again will come back to the flask. 
    7.    Repeat the process for about 16 – 18 hrs for complete extraction. 
    8.    Remove the sample and evaporate most of the ether from the mixture of crude fat and ether obtained during extraction.
    9.    Evaporate excess of ether from the crude fat sample by evaporation on a water bath. Evaporate till it is free from the fumes of ether. Record the weight (C).

Materials Required

Sample, Liebig condenser, digestion flasks (700-750 ml cap), conical flasks, filtering cloth (thick linen cloth for clear filtration) reagents, muffle furnace, crucibles.

Reagents

    1.    0.255 N Sulphuric acid solution : Dilute 2.5 g (1.36 ml) of concentrated H₂SO₄ to 200 ml. Ensure correct concentration by titration.
    2.    0.313 N Sodium hydroxide solution: 2.504 g NaOH / 200 ml water nearly free from sodium carbonate. Ensure correct concentration by titration.
    3.    Asbestos Chips: gooch grade, medium fibre, acid wash and ignited
    4.    10% Potassium sulphate (K₂SO₄) solution: Dissolve 10 g of Potassium Sulphate (AR) in water and make up to 100 ml.

Materials Required

Spectrophotometer, ethyl alcohol, beakers, pestle and mortar etc. 

Procedure

    1.     Preparation of sample extracts
        a.    Liquids : Centrifuge the juice at 5000 rpm for 4-5 min., and collect the supernatant. For liquid samples prepare a 40 % solution in ethyl alcohol. To 30 ml of the sample add 45 ml of ethyl alcohol and mix thoroughly. Filter through Watman 
No. 1 paper.

        b.    Semi-solid samples: To 15 g of blended sample add 15 ml of distilled water and 45 ml of ethyl alcohol. Mix thoroughly and filter through Watman No. 1 paper.
        c.    Dried products: Extract known quantity of sample (4-6 g) with 100 ml of 60% ethyl alcohol for 12 hrs and filter through Watman No. 1 filter paper.
    2.     Measure the absorbance of the samples at 440 nm for non-enzymatic browning and 400 or 420 nm for measurement of colour.
    3.     Prepare 60% ethyl alcohol solution as blank. Add 30 ml of distilled water to 45 ml of absolute alcohol and use as blank.

Materials Required

Ostwald viscometer, stop watch, sample, distilled water, thermometer.

Procedure

    a.    Take sample and distilled water. Record their temperatures (they should be same for correct estimation). If the temperatures are not same bring both to a specific temperature say 20ºC or the room temperature.
    b.    Clean and dry the Ostwald viscometer properly before use
    c.    Fill the ostwald viscometer with distilled water and record the time taken (T₁) for the a known volume of water to flow through the orifice.
    d.    Empty the viscometer and dry it
    e.    Fill the ostwald viscometer with sample juice or liquid and record the time taken (T₂) for the a known volume of sample to flow through the orifice of the same viscometer.
    f.    Calculate the relative viscosity using the following formula

Materials Required

Specific gravity bottles, weighing balance, sample, pipettes, thermometer, distilled water 

Procedure

    1.    Take the sample and distilled water record their temperatures (they should be same for correct estimation). If the temperatures are not same bring both to 20ºC or the room temperature.
    2.    Clean and dry the specific gravity bottles properly before use.
    3.    Record the tare weight of the specific gravity bottle (T) alongwith the stopper.
    4.    Carefully fill the specific gravity bottle with distilled water up to the brim and then place the stopper tightly so as to exclude extra water. 
    5.    Dry the exteriors of the bottle with a tissue paper
    6.    Record the weight of (bottle + water) say A
    7.    Similarly, fill the same specific gravity bottle with test sample and record the weight (bottle + sample) say B
    8.    Calculate the specific gravity of solution using the following formula

Materials Required

Sample, reagents, beakers, conical flasks, pestle and mortar, funnels, volumetric flasks, pipettes, weighing balance, spectrophotometer/colorimeter.

Reagents

    1.    2% Metaphosphoric Acid Solution: Weigh 20 g of HPO₃ and dilute to 1 litre in water or 4% oxalic acid.
    2.    Dye Solution: Dissolve 100 mg of 2, 6 Dichlorophenol-indophenol dye (Phenolindo-2,6- dichlorophenol sodium salt, AR, C₁₂H₆Cl₂NNaO₂ 2-3H₂O) and 84 mg of sodium bicarbonate (sodium hydrogen carbonate AR, NaHCO₃) in hot (85-95ºC) distilled water. Cool and make up the vol 100 ml. Filter and dilute 25 ml of the dye to 500 ml with distilled water. 
    3.    Standard Ascorbic Acid: Weigh 50 mg of ascorbic acid (AR) and make up to 50 ml with 2% metaphosphoric acid or 4% Oxalic acid solution (1000 ppm i.e. 1000 µg/ml). Dilute 4 ml of this solution to 100 ml with 2% HPO₃ or 4% oxalic acid. (1ml = 40 µg ascorbic acid).

Materials Required

Sample, reagents, beakers, conical flasks, pestle and mortar, funnels, volumetric flasks, pipettes, hot plate, weighing balance, spectrophotometer/colorimeter.

Reagents

    1.    0.1 N NaOH: Dissolve 4 g NaOH (AR) crystals in sufficient water to make up the final volume 1 Litre.
    2.    1 % Phenolphthalein: Dissolve 1 g in 100 ml water. Readymade indicator solutions are more commonly used.
    3.    Alkaline copper Tartarate
        a.    Dissolve 12.5 g anhydrous sodium carbonate, 10 g sodium bicarbonate, 12.5 g potassium sodium tartarate and 100 g anhydrous sodium sulphate in about 400 ml of distilled water and make up the final volume to 500 ml.
        b.    Dissolve 15 g copper sulphate in distilled water. Add one drop of sulphuric acid and make up to 100 ml in distilled water.
    4.    Always prepare fresh Alkaline Copper Tartarate reagent by mixing 96 ml of sol. a. and 4 ml of sol. b. and before use.
    5.     Arsenomolybdate Reagent: Dissolve 5.0 g ammonium molybdate (AR) in 90 ml of distilled water. Add about 5.0 ml of concentrated sulphuric acid and mix well. Add 600 mg of disodium hydrogen arsenate dissolved in 50 ml water. Mix well and incubate the prepared reagent at 37ºC for 24-48 hr or 55ºC for 30  min. with constant stirring.

Materials Required

Sample, 0.1 N NaOH solution, 1% phenolphthalein indicator solution, beakers, conical flasks, pestle and mortar, funnels, volumetric flasks, pipettes, pH meter, shaker.

Reagents

    1.    0.1 N NaOH: Dissolve 4 g NaOH (AR) crystals in sufficient water to make up the final vol. 1 litre.

    2.    1 % Phenolphthalein: Dissolve 1 g in 100 ml water. Readymade indicator solutions are more commonly used.  

Procedure

Preparation of sample: For fresh fruits and vegetables, prepare a well blended, uniform pulp in a pestle and mortar and for processed products, take out a representative sample and blend it well so that it becomes uniformly soluble when added to water. Filter through a fine muslin cloth or coarse filter paper if felt necessary. The liquid samples can be taken directly for estimation.
    1.    Take out a known weight / vol. (say 20 g) of sample in a beaker (in 3 replicates).
    2.    Make it to a known vol. (say 100 ml) with added distilled water.
    3.    Take 10 ml of this aliquot in a conical flask.
    4.    Add 1-2 drops of phenolphthalein indicator into the aliquot.
    5.    Titrate against 0.1 N solution of NaOH till light pink coloured end point is obtained.
    6.    For coloured products, i.e. tomato products where judgment of light pink colour is difficult, titration may be done over a shaker, and digital pH meter may be used for continuously measuring pH of aliquot which would show a steady increase with more and more addition of 0.1 N NaOH. Titre value may be recorded when pH of 8.3 is obtained.
    7.    Record the titre value and calculate the acidity of the sample as per the given formula.

Materials Required

Fruit/ sample, refractometers, thermometers, standard solutions of known TSS, temperature correction Tables.

Procedure

    1.    Calibrate refractometers of all ranges to be used.
    2.    The TSS of the juices/pulps/fresh fruits can be measured with the one having lowest range i.e. 0-32º Brix while, for measuring the TSS of concentrates, syrups, squashes, jams, jellies etc. refractometers of the higher ranges are made use of.
    3.    Put a drop of material on to the glass surface of refrectrometer’s prism, cover gently with the lid and observe the TSS against light.
    4.    Measure the temperature of the liquid which is being evaluated and apply temperature corrections (Annexure III).
    5.    Record the corrected value as the TSS of the sample.

Materials Required

Sample, hot air oven, weighing balance, crucibles, muffle furnace, lead pencil / marker etc.

Procedure

    1.    After following the procedure for the determination of moisture (in silica crucibles as given in previous chapter) the same sample can be used for the determination of ash. 
    2.    Heat the dried sample in the silica crucibles over a heater/hot plate/burner to burn the carbon.
    3.    When it becomes completely black and no more smoke comes out of the sample, shift them to muffle furnace.
    4.    After heating the samples in muffle furnace, all the marks of pen / pencil/ marker are lost, so one would not be able to identify the samples and error of weights may occur. Therefore, it is advised to place the samples in the furnace in one or two rows and draw the diagram on a piece of paper for identification purpose.

Materials Required

Fruit, vegetable or product sample, hot air oven, weighing balance, crucibles, petri plates, lead pencil / marker etc.

Procedure

    1.    Take crucibles  or petri plates and record the tare weight of crucibles / petri plates (C) and mark them
    2.    Cut the sample into small and thin pieces (if solid)
    3.    Put the sample into the crucibles / petri plates in three replications
    4.    Record the weight of crucibles + sample (C + S)
    5.    Put in hot air oven for drying at 70 + 2ºC.
    6.    Record the loss in weight after every 1-2 hrs till it becomes constant
    7.    Calculate the moisture and total solids. 

Materials Required

Cut flowers, 1000 ml conical flasks, scissor, tape, distilled water, chemicals, weighing balance, volumetric flasks, labels, thermometer (max. & min. type) and hygrometer. 

Procedure

    1.    Collect fresh spikes of flowers
    2.    Cut at the base keeping about 25-60 cm of the cut flowers stick (uniformly for each flower).
    3.    Prepare Pulsing/ Vase solutions.
    4.    Put the prepared flower spikes in labeled conical flasks containing different Pulsing/ Vase solutions (for a known period of time).
    5.    Record the weight of the spikes and other observations daily.
    6.    Record the temperature and relative humidity of the storage chamber daily.
    7.    Analyse the recorded data and draw conclusion about the best vase solutions for the selected cut flower.

Materials Required

Apple (or any local fruit), fruit mill, hydraulic press, weighing balance, Refractometer/sugar pectinol, diammonium hydrogen phosphate, Saccharomyces cerevisiae culture, Potassium metabisulphite (KMS) etc.

Procedure

    1.    Take a known quantity of apple (or any other fruit) say 20 Kg
    2.    Extract the juice as discussed in earlier exercises.
    3.    Add about 200 ppm of kms.
    4.    Add sugar syrup to increase the TSS to about 20 – 24ºBrix.
    5.    To about 10 Kg of juice diammonium hydrogen phosphate (10 g) and pectinol (20-25 g are added).
    6.    Take about 500 ml of this mixture in a conical flask and add pure Saccharomyces cerevisiae culture @ 1 % and plug the neck with cotton. Keep at 22-24ºC to complete the fermentation within one day and yeast culture is ready.
    7.    Add this culture to about 10 Kg of must for further fermentation (i.e. culture is added @ 5% therefore 500 g is added to 10 Kg must).
    8.    Record the TSS of the must before fermentation.
    9.    Keep must for fermentation in big jars (narrow mouth) filled to about 75 % of their volume. Close the mouth of jars or bottles with cotton plug.
    10.    Allow fermentation to take place at 22-24ºC for about 10–15 days.
    11.    When no more bubbles are coming out of the jars, fermentation is complete. At this stage the TSS reaches about 7º Brix.
    12.    Siphon the wine. Add filter aids if wine is not clear.
    13.    Blend the wine with sweetening agents if required.
    14.    Fill in beer bottles by keeping a head space of about 2.5 cm followed by crown corking them.
    15.    Pasteurize the bottles by keeping at 62.5ºC for 20 min.

Materials Required

Dehydrator, balance, thermometer, sulphur dioxide, blanching pan, fruits / vegetables, polythene or aluminium bags.

Procedure

    1.    Select sound fruits or vegetables 
    2.    Record their initial weight and wash them properly in plain water to remove any dirt or extraneous matter. 
    3.    Peel with stainless steel knife (as the case may be) and cut into thin uniform pieces or slices of  0.2-0.5 mm thickness
    4.    Blanch the slices in boiling water for 1-2 min. to inactivate the enzymes followed by immediate cooling.
    5.    Treat the slices with sulphur (sulphuring or sulphiting) in order to prevent darkening of the product during drying. 
    6.    Dry the slices in a mechanical air dehydrator at about 55 + 5oC temperature.
    7.    Record the weight of the product after every 2 hr till it becomes (almost) constant i.e. when there no more (significant) loss of moisture from the product.
    8.    Pack the product in ploythene or aluminium laminated pouches and seal them air tight. 
    9.    If it is to be converted into powder, the dried product can be ground in a grinder before packing.
    10.    Label the packages and store them in a cool dry place.
    11.    Plot the drying rate curve of the product on a graph paper and analyse it.
    12.    Record the initial and final moisture content of the product (as discussed in Exercise No. 19). 

Materials Required

Canned product, weighing balance, can cutter, vacuum/pressure guage, seam checking guage, Refractometer / Salometer etc. 

Procedure

    1.    Take a canned product say canned peach.
    2.    Record the weight of the can (A)
    3.    Record the information marked on the label i.e net  weight, date of packing, etc
    4.    Observe the can externally for the concavity of the lid.
    5.    Record the vacuum of the can by using a vacuum guage
    6.    Cut the lid of the can with a can cutter
    7.    Record the head space
    8.    Put all the contents over a sieve and let the liquid drain
    9.    Record the weight of empty can (B) to calculate net contents
    10.    Record the drained weight of the pieces.
    11.    Record whether the liquid is syrup or brine
    12.    Record the TSS of the salometer reading of the liquid (as the case may be)

Materials Required

Fruits or vegetables, stainless steel knife, steel pans, Can Body Reformer, Flanger, Double seamer, weighing balance, Refractometer / Salometer, sugar or salt etc. 

Procedure

    1.    Wash the selected fruit or vegetable (as the case may be) 
    2.    Cut into pieces or slices (the size and shape may depend on the fruit/ vegetable but it should not be too large or too small)
    3.    Blanch the material in boiling water for 1-2 min for effective inactivation of enzymes. 
    4.    Prepare the sugar syrup of strength 40o Brix or brine of 1-3 % strength.
    5.    Prepare the can body using a can body reformer and flange the ends in a flanger.
    6.    Seal the base plate using first and second roller operations of the double seamer. 
    7.    Transfer the prepared fruits / vegetables into the cans. 
    8.    Pour in hot syrup or brine into the cans.
    9.    Place the lid over the top of filled can. (follow the first roller operation of the double seamer, if the cans are OTS cans)
    10.    Exhaust the cans in boiling water for about 10 min. to exclude any dissolved air out of the tissues or syrup/brine.
    11.    When the temperature of the centre of can reaches 79-80 ºC for fruits or 82ºC for vegetables, remove the cans from the exhaust box and seal them properly (follow the second roller operation of the double seamer, if the cans are OTS can).
    12.    Process the sealed cans at 100ºC and 115-121ºC for fruits and vegetables respectively for 15-30 min in case of fruits and 25-45 min. in case of vegetables.
    13.    Cool the cans immediately in cold water and air dry them at room temperature.
    14.    Label and store in a cool dry place.

Materials Required

Tomato fruits, pulper, steel pans, weighing balance, refractometer, sugar, salt, spices, acetic acid, citric acid, muslin cloth etc.

Procedure
I. Puree

    1.    Extract fruit pulp by Hot process as told by the teacher.
    2.    Record the TSS of the pulp.
    3.    Concentrate the pulp by heating to 12º Brix (heavy puree)
    4.    Hot fill the boiling puree into pre-sterilized glass bottles (200 ml cap.)
    5.    Seal the bottles by crown corking
    6.    Heat process in boiling water in a big aluminium pan for 15-20 min. 
    7.    Cool the bottles to room temperature as quickly as possible.
    8.    Label and store at a dry place.

Materials Required

Fruits or fruit pulp, steel pans, weighing balance, refractometer, sugar, salt, spices, acetic acid, citric acid etc. 

Procedure

    1.    Extract fruit pulp as told in earlier exercises. 
    2.    Take a known quantity of freshly extracted or preserved pulp.
    3.    Weigh sugar (about half the weigh of pulp).
    4.    Heat pulp and sugar over a gas flame.
    5.    Add spices, chillies, salt, citric acid (if required) etc. and cook
    6.    Record the TSS to judge the end point. It should be more than 50o Brix.
    7.    Add measured quantities of acetic acid and sodium benzoate at the end.
    8.    Cool and pack in pre-washed and sterilized glass jars
    9.    Label and store.

Materials Required

Lime fruits, green chillies, ginger salt (common), stainless steel pans, kinives, weighing balance, spices etc. 

Procedure

    1.    Select sound and mature fruits of lime, mature but green chillies having good size and ginger rhizomes.
    2.    Wash the lime fruits, ginger and chillies properly in running cold water.
    3.    Cut the lime fruits into pieces / halves. 
    4.    Remove the stalks of the chillies and cut into longitudinal slices. Peel ginger and cut into long thin slices.
    5.    Put the lime pieces, chilli and ginger slices in a wide mouthed pre-sterilized glass jar 
    6.    Add common salt @ 250g / Kg of material.
    7.    Squeeze some of the juice over the slices
    8.    Stir the mass well mixing thoroughly
    9.    In case the juice does not cover the material completely, add pre-boiled and cooled 5% solution of citric acid.
    10.    Keep the jar in Sun for about a week with occasional shaking of the material.
    11.    When the lime pieces start turning light brown, the pickle is ready for consumption.