CHAPTER ONE

1.0    INTRODUCTION

The soy is a low cost source of protein that has been consumed in Asian nations for many countries. The rapid growing population fo the developing countries is facing acute shortage of protein, Soy bean is rich protein content and contains fiber.

Soybeans are the least processed form of Soy protein, its available in most grocery stores, they can be purchased in fresh, frozen or roasted forms. These beans can be eaten alone, like peas or added to salads and stir fies.

Tofu: Curdling Soy mil with a coagulant makes tofu or bean curd its available in both soft and firm forms, tofu can be used in a variety of recipes to partially replace either meat or diary product due to the common use of calcium sulphate as the curdling agent, Tofu can also be a good source of calcium (Chdi wenm et al; 2000).

Soymilk: Soymilk is another high quality source of Soy protein that is an alternative of diary animal milk and available in variety of forms including plain, vanilla and chocolate, it can also be used to replace milk added to coffee, tea or cereal.

Human beings are the only species to consume milk past childhood. We are also the only species to consume the milk of another species. There are some great nutritional benefits to milk, for example milk naturally contains a readily absorbable form of calcium and has higher quality protein than soy milk. In this condition known as lactose intolerance, it causes unpleasant abdominal symptoms including stomach cramps, flatulence and diarrhea. Lactose intolerance is reality for 75% for the world population, even though consuming diary is unnatural and problematic for many people. There are many people who cannot drink cow milk because of a milk allergy or out of a values choice like vegan. Soymilk is a healthy drink and is important for people with above problems and had been the first production ever prepared and consumed by human since long ago. Soymilk not only provides protein but also is a source of carbohydrate, lipid, vitamins and minerals.

Milk composition describes the chemical and physical properties and effect of pasteurization on the compound in milk. The variation in milk composition are:

·         Carbohydrate (Lactose)

·         Fat/Oil

·         Protein

·         Vitamins and minerals.

·         Enzymes.

How the body digests foods and absorbs nutritional components

          Food undergoes mechanical, chemical and enzymatic digestion as it travels from the mouth from the mouth to the stomach to the intestines. Many chemicals, enzymes, hormones, glands and organs are involved in the absorption of nutrients from food.

          The first step is mechanical digestion in the mouth chewing food to break it into small pieces. Saliva, secreted by the salivary gland, contains water that helps dissolve food to make it easier to swallow. Saliva contains the enzyme amylase that begins to break down larger carbohydrate molecules, which makes them easier to digest in the small intestine. Mechanical digestion continues in the stomach as it churns the food and mixes it with gastric juice. The stomach contains hydrochloric acid that dissolves additional foods components that didn’t dissolve in saliva. The highly acidic environment in the stomach causes protein to unfold (denature) so that they can interact with the enzyme pepsin, which breaks down proteins into smaller molecules (peptides) for easier digestion in the small intestine. Gastric lipase begins to break down fats in digestion in the small intestine.

          The majority of food digestion occurs in the small intestine, the duodenum. As food leaves the stomach and enters the duodenum, hormones signal the pancreas to release sodium bicarbonate to neutralize the stomach acid so that digestive enzymes can act. The pancreas releases enzymes for the digestion of all major food components. Proteases to break down proteins into small peptides, amylases to break down fats. Hormones trigger the release of bile that is produced in the liver and stored in the gall bladder to aid in emulsification of fats for digestion and absorption. Breakdown of peptides into amino acids and small carbohydrate into individual sugar molecules occurs by enzymes that are secreted by the intestinal cells.

          The main carbohydrate in milk is lactose which is a molecule that must be broken down (hydrolyzed) into its two individual sugars (glucose and galactose) before absorption. Lactose is broken down by the enzyme lactase that is secreted by the intestinal cells. Lactase often decrease as people age or may be deficient in some populations which can result in lactose mal absorption or lactose intolerance.

          Absorption of nutrients occurs in the second and third section of the small intestine, the jejunum and ileum. Proteins, carbohydrate, fats, fat-soluble vitamins, water soluble vitamins and mineral are absorbed by diffusion across the cell membranes, other require transporters on binding proteins the absorption of fats involves a complex network of lipid carriers.

          After absorption of nutrients in the small intestine, the remaining mass moves into the large intestine. The function of the large intestine is to absorb water and sodium and prepare the remaining mass for excretion by the body.

1.1    IMPORTANCE OF MILK

          Milk is one of the greatest blessings that is given to human by nature. Milk is considered a complete and great food. People is past used milk and things made by it most of the time like cheese, butter in subcontinent. According to research of health experts the secret behind long ages and good health of people of subcontinent in past was use of milk.

          Milk is proved a complete food from latest scientific researchers, all the important elements that are needed for body are in milk. Milk has hundreds of benefits to our bodies, health and mind, specially the milk of cow and goat as many benefits. The milk of cow keeps the stomach system of old people and kids strong, most of the people drinks milk while sleeping but its not the correct time of drinking it. The correct time of drinking milk is in morning. Milk even powdered milk is a nutritious, cost, efficient source of protein minerals and vitamins, milk is now often pushed aside to make space for excessively sugary sodas, juice and sports drinks that contribute empty calories to diets already so full of unhealthy choices that many populations are now experiencing unmatched levels of diet-related obesity, diabetes, heart disease and cancer.

          Teenagers also should replace sugared beverages with milk. Because adolescents undergo extra ordinary physiological changes, the required energy and nutrient-dense foods for optimal development of hormonal, muscular, circulatory and reproductive systems. Teen’s calcium intake must be accompanied by physical activity to optimize bone-calcium integration and that adolescence is the best time to increase bone density to thwart later life bone fragility and osteoporosis. Without calcium, vitamin D and phosphorous, adults of all ages risk bone degeneration, so milk remains essential. Other calcium rich, non dairy foods such as tofu, broccoli and spinach but some contain compounds that compromise the absorption of calcium. Spinach is high in oxalates, which hinder calcium absorption and the calcium in other vegetables such as broccoli, is not as readily absorbed as the calcium in milk.

          Children should be served milk, not high sugar beverages milk’s outstanding protein is built from balanced amino acids that are biologically available that is easily absorbed and used. Milk’s Calcium fortifies a child’s developing bones, teeth and brain tissue and contributes to chemical reactions at the cellular level that govern muscle and neurological function. Fortified milk also provides vitamin D, a critical vitamin that helps the body absorb both calcium and phosphorous for bone integrity, promotes red blood cell production, aids digestive and nerve processes and supports immunity.

          Milk and diary products contain many nutrients and provide a quick and easy way of supplying these nutrients to the diet within relatively few calories.

          Milk, cheese and yougurt all provide the following beneficial nutrients in varying quantities.

·         Calcium – for healthy bones and teeth.

·         Phosphorous – for energy release.

·         Magnesium – for muscle function

·         Protein – for growth and repair

·         Vitamin B12 – for production of healthy cells.

·         Zinc – for immune function

·         Riboflavin – for healthy skin

·         Folate – for production of healthy cells.

·         Vitamin C – for formation of healthy connective tissues.

·         Iodine – for regulation of the body’s rate of metabolism.

1.2    PRESERVATION OF MILK

Milk is a perishable commodity and spoils very easily. Its low acidity and high content make it the perfect breeding ground for bacteria including those which cause food poisoning (pathogens). Bacteria from the animal, utensils, hands and insects may contaminate the milk and their destruction is the main reason for processing. This preservation of the milk can be achieved by fermentation, heating, cooling, removal of water and by concentration or separation of components to produce foods such as butter or cheese.

          The degree to which milk consumption and processing occurs will differ from region to region. It is dependent upon a whole host of factors, including geographical and climatic conditions, availability and cost of milk, food taboos and religious restrictions, where processing does exist, many traditional techniques can be found for producing indigenous milk products.  These are more stable than raw milk and provide a means of preservation as well as adding variety to the diet. In addition, the introduction of western style diary products and the subsequent setting up of small scale dairies has provided more choice of diary products to the consumer. Infections in the animal which cause illness may be passed directly to the consumer through milk, it is therefore extremely important that quality control tests are carried out to ensure that the bacterial activity in raw milk is of an acceptable level and that no harmful bacteria remain in the processed products. Routinely is necessary to check the microbiological quality of raw milk using either methylene blue or resazurin dyes, these tests indicate the activity of bacteria in the milk sample and the result determine whether the milk is accepted or rejected. The type of animal its quality and its diet can lead to differences in the colour, flavour and composition of milk. Infections in the animal which cause illness may be passed directly to the consumer through milk. It is therefore extremely important that quality control tests are carried out to ensure that the bacterial activity in raw milk is of an acceptable level and that no harmful bacteria remain in the processed productions. Milk can be kept for longer periods of time if it is heated to destroy the bacteria remain in the processed productions. Milk can be kept for longer periods of time if it is heated to destroy the bacteria or cooled to slow their growth. Pasteurization an sterilization are the two most commonly used heat treatments. Technically, it is possible for both to be carried out on a small scale, but they are most usually performed on a larger industrial scale due to the need for qualified, experienced staff and accurate and strictly controlled hygienic processing conditions.