Key points for using coagulants for soy products
In the daily production of soy products, products often have poor water retention, dullness, inelasticity, rough texture, and poor taste. Situations such as low yield rate and high cost. In addition to requiring the selection of high-quality raw materials, an important reason is the improper handling and use of coagulants. In order to improve product quality and increase economic benefits, we are required to correctly understand and master the handling and use of coagulants during production. Coagulant is a protein substance that coagulates sol-like proteins into a gel-like form. The coagulants commonly used in production can be divided into two types: salts and acids. 1. Salt coagulants The most widely used salt coagulants in my country are brine and gypsum. (1) The chemical name of gypsum is calcium sulfate (CaSO4). According to its crystal water content, it can be divided into four types: raw gypsum, semi-parised gypsum, paris gypsum, and over-parised gypsum. The coagulation effect of soy milk is fastest on raw gypsum, slower on paris gypsum, and over-parised gypsum has almost no effect. Tofu made with gypsum as a coagulant has better water retention and elasticity than those made with brine as a coagulant, and its texture is also finer. Therefore, it is better to use gypsum as the coagulant for making soft tofu. Unbaked gypsum solidifies quickly when used, and the finished product has sufficient elasticity, but the operation is difficult to master. Therefore, plaster of paris is generally used. Gypsum must be baked and ground into powder before use. ① Baking of gypsum: Break the raw gypsum into small pieces of 0.5 kg to 1 kg and place them on both sides of the second hole of the pulp cooking stove. The texture of the gypsum should follow the direction of the fire, and should not be piled too high or too much to avoid affecting the fire. It is appropriate to stack 25 kilograms at a time. If the fire is burned for 8 hours a day, after baking for about 3 days, turn the gypsum upside down and bake for another 3 days. Plaster of Paris is white with no bright crystals. Brush off the ashes after taking it out and leave it for 20 days before use. If crystal gypsum remains inside the baked gypsum, it should continue to be baked. Otherwise, it will not be possible to make tofu by mixing raw and cooked gypsum together. At the same time, the gypsum cannot be over-baked, otherwise it will become over-cooked gypsum. ② Making gypsum slurry: Gypsum powder is difficult to solidify when directly sprinkled into soy milk. It must be made into gypsum slurry before it can be used. The preparation method is to take 0.5 kg of baked plaster of paris, put it into a mortar, slightly crush the gypsum with a grinding rod, add an equal amount of water, grind it with a grinding rod, and gradually add 1.5 kg to 2 kg of water. After the gypsum becomes fine and thick, add 2 kilograms of water and stir to make the water and gypsum slurry mix evenly. After a while, the coarser gypsum will settle down, and the suspension can be used to prepare some slurry. (2) Brine is the remaining mother liquor after seawater salt production. The main component is magnesium chloride (MgCl2) with a content of about 29%. It tastes bitter, so it is called bitter brine. When used as a coagulant, dilute it to 6~20°Be according to product requirements before use. Using salt brine as a coagulant has a fast coagulation speed, and the protein network tissue shrinks easily, so the tofu produced has poor water retention. Generally, it is more suitable to use salt brine as a coagulant for making dried tofu, fried tofu and other soy products. The resulting products have no astringent taste and have a better taste. (3) Magnesium chloride (MgCl2) is a magnesium chloride solid extracted from brine. Its properties are similar to brine and contains about 97% magnesium chloride. Since this product contains higher magnesium chloride than salt brine, it is a better soy protein coagulant. Before use, it should be dissolved in water to form a liquid, and its concentration should be controlled between 6 and 20°Be as needed. 2. Acid coagulants Acid coagulants mainly include organic acids such as acetic acid, lactic acid, gluconic acid and citric acid, but they are rarely used in production. (1) Gluconolactone is a recently developed new coagulant. It is a white crystal and is easily soluble in water. When it is dissolved in water, it will gradually be decomposed into gluconic acid. Under heating conditions, the decomposition speed will be accelerated. Gluconic acid can coagulate soybean protein. The coagulated soybean protein has good water-holding properties at 80°C to 90°C, and the made tofu has a delicate texture, sufficient elasticity and strength. Gluconolactone is suitable for making puree bagged tofu, which is convenient for mechanized production. Add gluconolactone to low-temperature soy milk, then pour the soy milk into a bag and seal it, and then heat it to convert the soy milk in the bag from gluconolactone into gluconic acid and solidify into tofu. (2) Lactide and lactic acid polymers can also be used as coagulants. After lactide is dissolved in water, it can be decomposed into lactic acid by heating, thereby coagulating the protein
Milk coagulant
Milk coagulant is made of animal and plant rennet, stabilizer, It is formulated with sweeteners, spices and functional auxiliaries. It can quickly coagulate milk in a few minutes at a high temperature range of 70-90℃, producing a new dairy product like tofu flower - "milk flower".
Mix this preparation into sugar powder or milk powder according to the amount, and you can make "milk candy" or "milk powder". You can get "milk candy" by brewing it with boiled milk or hot water respectively. A milk coagulant, characterized in that the preparation content is 3-12% (weight) calf rennet, 5-15% (weight) pineapple rennet, 20-50% (weight) papaya rennet, 10 -50% (weight) sweetener, 1-15% (weight) flavoring agent. 3-8% (weight) stabilizer, 0.2-0.4% (weight) food calcium chloride, 0.5-1.0% (weight) salt.