Question

Preparation of soyabean milk

Answer 1

Soyabean milk can be made from whole soybeans or full-fat soy flour. The dry beans are soaked in water overnight or for a minimum of 3 hours or more depending on the temperature of the water. The rehydrated beans then undergo wet grinding with enough added water to give the desired solids content to the final product. The ratio of water to beans on a weight basis should be about 10:1. The resulting slurry or pure is brought to a boil in order to improve its nutritional value by heat inactivating soybean trypsin inhibitor, improve its flavor and to sterilise the product. Heating at or near the boiling point is continued for a period of time, 15-20 minutes, followed by the removal of an insoluble residue (soy pulp fiber) by filtration.

Answer 2

Theory:

Soy milk (also called soya milk, soymilk, soybean milk, or soy juice) and sometimes referred to as soy drink/beverage is a beverage made from soybeans. A stable emulsion of oil, water, and protein, it is produced by soaking dry soybeans and grinding them with water. Soy milk contains about the same proportion of protein as cow's milk: around 3.5%; also 2% fat, 2.9% carbohydrate, and 0.5% ash. Soy milk can be made at home with traditional kitchen tools or with a soy milk machine.

The coagulated protein from soy milk can be made into Tofu, just as dairy milk can be made into cheese.

Requirements:

Beakers, pestle and mortar, measuring cylinder, glass rod, tripod-stand, thermometer, muslin cloth, burner. Soyabeans, buffalo milk, fresh curd and distilled water.

Procedure:

1) Soak about 150g of Soya beans in sufficient amount of water so that they are completely dipped in it.

2) Take out swollen Soyabeans and grind them to a very fine paste

3) Take out swollen Soyabeans and grind them to a very fine paste and filter it through a muslin cloth. Clear white filtrate is soyabean milk. Compare its taste with buffalo milk.

4) Take 50 ml of soyabean milk in three other beakers and heat the beakers to 30°, 40°and 50°C respectively. Add ¼ spoonful curd to each of these beakers. Leave the beakers undisturbed for 8 hours and curd is formed.

5) Similarly, take 50 ml of buffalo milk in three beakers and heat the beakers to 30°, 40° and 50°C respectively. Add ¼ spoonful curd to each of these beakers. Leave the beakers undisturbed for 8 hours and curd is formed