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Microwave Oven Drying

Microwave drying is quick and relatively simple. It takes only a few minutes and provides dried flowers that look fresher and more colorful than obtained by other methods. Flowers with thick petals like magnolia are not suitable for drying in microwave. Since flowers vary in moisture content, texture and density, care should be taken to use the same sized flowers from one species at a time. It has been found that many flowers held almost true to life color and form using this process. Brightly colored flowers are best to dry. Flowers such as lilies, roses, violets, zinnias, and dahlias work well with this process.

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.

The method of preserving various food stuffs by drying them, and thereby depriving microorganisms of the water necessary for their growth, has been known for centuries. According to Marco Polo’s accounts of his travel in Asia in 13^th century, soldiers of Kublai Khan carried dried milk on excursions. Before it was used, water was added to a portion of dried material. Mixing was accomplished by movement of the horse during riding on the trip. The recombined product was then consumed at the mealtime. The belief is that part of the fat was removed from the milk before drying and dehydration was accomplished by solar heating.

Drying is defined as the removal of the liquid, usually water, from a product by evaporation, leaving the solids in an essentially dry state. Today the production of dried milk and milk products has become important segment of dairy industry. Dry milk provides a means of preserving the excess milk supply during the flush season for use during the lean season. The value added dried dairy products like malted milk foods, infant food and infant formulae and dairy whiteners are convenient ready to use products having wide acceptance. The water content of milk powder ranges between 2.5 and 5%, and no microbial growth occurs at such low water content. Drying extends the shelf life of milk, simultaneously reducing its weight and volume. The main purpose of drying milk are: a) to improve the storage life of the product due to low moisture content, b) to reduce cost for storage and transportation of product due to reduced bulk, and c) to provide convenient product for utilization in many dairy and food preparations.

The production of dried milks to a great extent is now being governed by the market requirement and to some specialized use of such products. Considerable quantities of dried skim milk powders are being used extensively in the preparation of ‘Reconstituted and Recombined milks”. Milk powders are also used extensively in the manufacture of ice cream, bakery products, confectionary products, cottage cheese and in other cheese varieties. The greatest proportion of milk powder is utilized in confectioneries, such as milk chocolate, caramels, soft sweets, coatings, biscuits and cakes. In these products, milk powder has a special effect on the quality of particular products: it improves consistency, flavour as well as nutritional value and shelf life.

Abstract

Food proteins are among the commonly used ingredients by food manufacturers to produce different products with desired characteristics. Due to several nutritional and functional properties, proteins have different functions in various food products in addition to their role in metabolic system of the human body. Dilute or concentrated solutions of pure proteins or unprocessed food products which are rich in protein are very sensitive to deterioration or degradation by microorganisms and thus have short shelf life at ambient temperatures due to their highly moist structure and high protein content. Drying is one of the best methods that can guarantee preservation, a longer shelf life, chemical or thermal stabilization and resistance against other stresses. A full understanding of stresses encountered during drying is needed to choose an appropriate drying process and to optimize this process for maximum product quality. A number of methods have been used by various researchers to dry protein-containing foods. Among these methods, freeze drying and spray drying are the most common techniques. Sun drying, convective hot air drying, vacuum drying, heat pump drying, radio frequency drying as well as combined or hybrid drying methods with two or more of the drying methods have also been developed.

Introduction

Flowers are associated with mankind since the dawn of civilization. Flowers are required for all the functions, ceremonies, rituals and celebrations from dawn to the dusk. In India, flowers are mainly grown for cut flowers and loose flowers purpose. By using best postharvest techniques, we can preserve the flowers ranging from few days to few weeks, but drying or dehydration is a technique by which flowers can be preserved for months to years. India has rich biodiversity comprising of wide variety of ornamental trees, shrubs, climbers, etc. which are not being used as fresh or loose flowers but their branched, twigs, flowers, fruits, cones, stems, roots, bark, etc. can be dehydrated to preserve their beauty and for utilization in dry flower industry.

Q. 1 LSU dryer was developed at
(A) London State University       (B) Ludhiana State University
(C) Lucknow State University     (D) Lusiana State University

1. Introduction

Drying is a thermo physical and physicochemical process, which involves removal of excess water from a solid, semi-solid or liquid food material by evaporating it into vapour phase on applying heat, to reduce growth of microorganism or to completely eliminate their growth. Hence, reducing the water activity increases shelf life of food products. Drying medium for carrying evaporated moisture can be air or steam. Benefits of drying include increase in shelf life, easy to transport, handle food material and reduce packaging cost as it reduces bulk weight. 

Removal of water from the food by non-conventional energy source like sunlight, wind, and a smoky fire. Drying (dehydrating) food is one of the oldest and easiest methods of food preservation.

Dehydration

Dehydration is the process of removing water or moisture from a food product under controlled condition like temperature, relative humidity, air flow, etc.

Principles of Drying and Dehydration

Drying removes the moisture from the food so that bacteria, yeasts and moulds cannot grow and spoil the food. It also slows down the action of enzymes, but does not inactivate them. Dried food items can be kept almost indefinitely, as long as they are not rehydrated.

Dryland agriculture refers to cultivation of crops entirely under natural rainfall without irrigation. It is a form of subsistence farming in the regions where deficit of the soil moisture retards the growth of water consuming crops like rice (Oryza sativa), sugarcane etc. Dryland areas are characterized by low and erratic rainfall and no assured irrigation facilities. Dryland agriculture is important for the economy as most of the coarse grain crops, pulses, oilseeds, and raw cotton are grown on these lands. Dryland areas receive annual rainfall between 500 and 1200 mm.

Types of Dryland Agriculture

Depending on the amount of rainfall received, dryland agriculture has been grouped into three categories:

Dry farming: It is production of crops without irrigation in areas where annual rainfall is less than 750 mm. Crop failures are more frequent under dry farming condition owing to prolonged dry spells during crop period. The growing season is less than 200 days. It is generally practiced in arid regions of the country

Introduction

India has predominantly agrarian economy with just 2.5% of the world’s geographical area, but has about 17% of its population. India’s population has increased from 361 million in 1951 to 1270 million at present: a three and half-fold increase in a span of 63 years. By 2020, India will need about 294 million tonnes food grains (Kumar, 1998). However, only 259.29 m t was produced in 2011–12 (Directorate of Economics and Statistics, Ministry of Agriculture, 2012), implying that about 34 m t additional food grains have to be produced from the same or even lesser land area.

The term “Poultry” indicates to all the domesticated species of birds like chicken, ducks, turkeys, Japanese quail, guinea fowls, geese, pigeons, ostrich, emu etc. Ducks account for 7% of poultry population and are mostly found in coastal states of the country and in states with more lakes and rivers like West Bengal, Orissa, Andhra Pradesh, Tamil Nadu, Kerala, Assam, Jammu and Kashmir and Tripura. Duck farming is still in primitive stage and indigenous ducks outnumbered the exotic ducks in spite of their inferior performance.

In India 90-95% of ducks are indigenous or nondescript types, which are hardly, with mediocre egg production and highly suitable for extensive system of rearing.

Introduction

Ducks are domesticated before 3000-4500 years. Ancestor of domestic ducks is wild mallard duck (Anas boschos) which are broody. Scientific name of domestic duck is Anas platyrhyncos. Duck farming is the part of poultry farming system. Duck can be raised for meat and eggs. In most part of the world, duck ranks next to the chicken in terms of egg and meat production. Commercial duck farming is increasing as this business has good potential to earn money through egg production. Duck can be feed on agro-industrial waste, swamp and marshy areas. These hardy birds can survive in such as areas where no other agricultural crops could be grown and other livestock raised. Duck farming business is a very profitable business as there are many duck breeds available all over the world. For commercial duck egg production and breeding, must go through water sources for raising ducks. It will reduce cost of feed. Duck can survive without water; but they need water pond kind things for fertile egg laying and mating. If pond is available then it is well and good for commercial duck farming. Chromosome number of duck is 80. Duck sound is whimpering or betch, honk. Incubation period of duck egg is 28 days. Egg weight duck is 72 gm.

Etiology Herpes Virus

Variation in pathogenicity of virus strains has been reported, but all strains appear identical immunologically.

Occurrence

The disease was first reported in the Netherlands in 1923. The disease has been confirmed in France, Belgium, Canada, India, Thailand, England, Hungary, Austria, Denmark and Vietnam, and suspected in China.

DVH is a highly fatal infection of young ducklings. Lesions are primarily in the liver.

It seems that you’re interested in integrated farming systems involving aquaculture combined with other types of livestock. Integrated farming systems(IFS) are agricultural systems that combine different agricultural practices to maximize productivity, enhance sustainability, and diversify income sources. Here’s a brief overview of how these combinations work:
1. Duck/Poultry cum Fish: This system integrates duck or poultry rearing with fish culture in a common water body. Ducks or chickens roam over or near fish ponds, and their droppings directly fertilize the pond, increasing natural fish food (plankton).
• Overview: This system involves raising ducks or poultry alongside fish in a shared environment, often in ponds.
• Benefits
º Nutrient Cycling: Duck or poultry manure can supply nutrients to the water, enhancing fish growth.
º Pest Control: Ducks help control pests in rice paddies while providing additional protein sources.
º Water Quality: The movement of ducks or poultry can improve the aeration of water and help manage algae.
• Considerations: It’s essential to manage feeding and water levels to prevent over-fertilization and maintain good water quality.

The Dumas combustion method, named after the renowned French chemist Jean-Baptiste Dumas, is a widely recognized analytical technique employed in the determination of the elemental composition of organic compounds. This method involves the complete combustion of a sample in an oxygen rich environment, followed by the separation and subsequent analysis of the resulting combustion products.

Principle

The Dumas combustion method involves the complete combustion of a sample in the presence of excess oxygen. The nitrogen present in the organic compound is converted into nitrogen gas (N2 ), which is then measured quantitatively. The process can be summarized as follows:

i. Combustion: The sample is combusted at high temperatures (typically around 900-1000°C) in the presence of oxygen. This results in the conversion of all organic material into carbon dioxide (CO2 ), water (H2 O), and nitrogen gas (N2 ).

ii. Removal of Interfering Gases: The combustion products are passed through various reagents to remove interfering gases such as CO2 and H2 O.

iii. Detection of Nitrogen: The nitrogen gas is then measured, often using a thermal conductivity detector (TCD) or another suitable detection method.

Durian, an exotic fruit, native to Malayasia and Indonesia, is considered to be the ‘King of all fruits’ in South East Asia. The term ‘Durian’ has been derived from the Malay word ‘Duri’ which means thorn. The fruit has a tough, thick, thorny husk that resembles the husk of jackfruit. The notorious odor has given rise to the unflattering terms like “Civet Cat Tree”, and “Civet Fruit” in India and “Stinkvrucht” in Dutch. Durian is delicious, soft and succulent with a distinctive sulphuric smell. It is characterized by the rich, buttery smooth and luscious flesh. The fruit is distinctive for its large size, unique odour and formidable thorn-covered husk. The fruit is a good source of carbohydrates, protein, dietary fiber and energy. Some of the other durian fruit benefits are their high iron content and lack of cholestrol. It is rich in vitamin B, C and E, as well as in amino acids. The jelly is prepared from over ripe fruits which is sour in taste.