Soak soybeans and grind them into soybean milk. \ x0d \ x0d \ Bring the soybean milk to a boil and remove the foam. \x0d\\x0d\ rushed into gypsum powder and stirred. \x0d\ Put the lid on, 10 will become tofu flower in a few minutes, \x0d\ blue pad cloth. \x0d\ Put the tofu flower in the basket. \x0d\ Fill it up. Wrap the tofu flower. \x0d\ put your heavy possessions on it. \x0d\ I think it's almost enough, so I turn the basket upside down. \x0d\ Remove the cloth. Perfect tofu leaves no trace on the cloth. \x0d\\x0d\ Gypsum powder is an essential thing to make tofu. 10 kg of soybean is enough, and the bean curd maker can put it according to his own estimation. If you put it too much, it will be astringent, but if you put it too little, the tofu will be thin and soft. \ x0d \ x0d \ Tofu is rich in nutrition, easy to digest and convenient to eat, and it is one of the favorite non-staple foods in China. \x0d\\x0d\ Raw material formula The main raw material for making tofu is soybean, and it is better to use new beans with neat particles, no impurities, no insect eyes and no mildew and deterioration. Secondly, some coagulants and defoamers are needed. \x0d\\x0d\ The coagulant used to make tofu generally uses bittern (magnesium chloride), which accounts for about 3% (solid) of raw materials. When it is used, it is diluted with water1:2, Baume16 ~18, and used after filtering. Tofu made from bittern is slightly rough and hard. Also known as North Tofu or Big Tofu. Using gypsum (calcium sulfate) as coagulant to make tofu, the finished product has a large fraction, white color and soft texture, also known as water tofu or south tofu. Before using gypsum, add water according to the ratio of 1∶ 1.5 to grind it, then add water to make it into 5 times suspended liquid, and cut the bottom for use. \x0d\\x0d\ Defoamer for tofu can be made by mixing oil residues or vegetable oils with calcium hydroxide according to the ratio of10:1,and fermenting into a thin paste, and then using it. The dosage is 1%. Emulsion silicone resin and liquid foam can also be used. \x0d\\x0d\ production method 1. foam. After strict acceptance and inspection, the first working procedure of soybeans is to put them into the material pool and soak them in water. \ x0d \ x0d \ soaking time should be treated differently according to the quality, water content, season, room temperature and different grinding mouths of soybeans, and everything can't be cut. In northern China, it can be soaked for12 ~14 hours in spring and autumn, 6 ~ 8 hours in summer and14 ~16 hours in winter. \x0d\\x0d\ Soak in cold water for 3-4 hours for the first time. When the water has no feed surface 150 mm and the soybean absorbs water, when the water level drops 60-70 mm below the feed surface, continue to add water once or twice, so that the beans can continue to absorb enough water and double the weight of the soaked soybeans. \x0d\\x0d\ In summer, it can be soaked to 90% open, with a slightly concave center and a slightly dark center color. In winter, it can be soaked to 100% open, and the rubbed watercress is milky white, with a light yellow center and a pH value of about 6. \x0d\\x0d\ If the grinding wheel is used to grind the slurry, the soaking time should be shortened by1~ 2 hours. \x0d\\x0d\2. Abrasive. Abrasive is the second process of making tofu. Soaked soybeans should be washed by water or water before grinding. When grinding with grinding wheel, it needs to be washed clean in advance, adjust the spacing between grinding discs, and then drip water to feed. It is best to try grinding at first, and then grind at normal speed after the trial grinding is normal. \ x0d \ x0d \ The dripping and blanking of abrasives shall be coordinated, and water or materials shall not be cut off in the middle, and the paste shall be smooth, appropriate in thickness and thickness, and even before and after. \x0d\\x0d\ When using the stone mill, the grinding body should be washed clean, the grinding cover and funnel should be properly pressed, and the top thread should be adjusted. When the mill is started, there is no stopping of material and water. \ x0d \ x0d \ abrasives should be ground as much as needed to ensure the fresh quality of abrasives. \x0d\\x0d\ In case of temporary power failure, water cut-off or mechanical failure, the bean materials should be taken out immediately and spread on the cement floor, and water should be pumped out in large quantities, so pay attention to ventilation. Rinse1~ 2 times with cold water before use, so as not to affect the quality of finished tofu. \x0d\\x0d\3. Filter. Filtration is the premise to ensure the quality of tofu products. At present, centrifuges are widely used in bean products factories all over the country. The use of centrifuges not only greatly reduces heavy manual labor, but also has high efficiency and good quality. \x0d\\x0d\ Use a centrifuge to filter, which should be coarse first and then fine, and be carried out in stages. The nylon filter screen is first used with 80 ~100 mesh, and then used with 80 mesh for two or three times. The filter screen is made into a trumpet-shaped filter with better filtering effect. \x0d\\x0d\ During the filtration, the residue is washed for three times and filtered clean, so as to make full use of the residue in the residue washing water. The protein content in the residue should not exceed 2.5%, and the water consumption for residue washing should be based on the "grinding paste" concentration. Generally, the total water consumption of 0.5 kg soybean (referring to soybean milk) is about 4-5 kg. \ x0d \ x0d \ centrifuge is an important mechanical equipment in bean products factory. During operation, the electromechanical safety operation procedures are strictly implemented and environmental sanitation is done well. \ x0d \ x0d \ 4. Boil the pulp. Cooking is also very important to the quality of tofu products. Usually, there are two ways to cook tofu, one is to use an open cauldron, and the other is a sealed cooking pot with modern equipment. \x0d\\x0d\ Use an open pot to cook the pulp, which should be fast and short, and the time should not exceed 15 minutes. Release immediately after the pot is boiled for later use. \x0d\\x0d\ Soymilk should be used in boiling to eliminate foam. The fire usually adopts a closed valve, and it is closed three times after three falls. Foam floats in the pot for the first time. After the foam closes the valve and sinks, open the valve again. Cracks can be seen in the middle of secondary foam floating, and transparent bubbles are generated. At this time, defoamer can be added to defoam, and then the valve is opened. When the pulp boiling reaches 97 ~100℃, the valve is closed, leaving a little residual gas to discharge the pulp. \ x0d \ x0d \ It is worth noting that raw pulp or raw water should not be injected into the boiled pulp, defoamer should be used according to the prescribed dosage, and the sizing in the pan should not be too full, and the pressure of boiling pulp should be sufficient, at least not less than 3kg/cm2. In addition, the boiled pulp should be boiled with it, and it should not be kept in the pan for a long time. \x0d\\x0d\ sealed stepped overflow cooking pot is a scientific cooking equipment, which can automatically control the temperature in each stage of cooking, with high accuracy and high cooking effect. \x0d\\x0d\ When this tank is used for cooking, a sanitary pump (milk pump) can be used to pump soybean milk into the bottom of the first cooking tank, and the convection generated by steam heating will make the slurry water at the bottom of the tank rise, overflow into the bottom of the second cooking tank through the interlayer slurry channel of the second cooking tank, contact with steam again, conduct secondary heating, and reach100 after repeated heating for five times. \ x0d \ x0d \ According to experience, the slurry temperature of each tank is 1 tank 55℃, 2 tanks 75℃, 3 tanks 85℃, 4 tanks 95℃ and 5 tanks 100℃. When the temperature of the slurry exceeds 100℃, the protein denaturation will seriously affect the subsequent process treatment. \x0d\\x0d\5. Refine. Boiled slurry should be filtered with 80 ~100 mesh copper gauze screen, or finely filtered with vibrating screen to eliminate trace impurities, chaff and swollen dregs in the slurry. Don't be too hasty when adding fine slurry, and the slurry flow rate should be consistent with the filtrate flow rate, that is, the fast flow rate of filtration is larger, and the slow flow rate of filtration is smaller. For large batches, consider setting two fine sieves. \x0d\\x0d\6. Solidification. Coagulation is the key to determine the quality and finished product rate of bean products. First, we should master the concentration and pH value of soybean milk, use coagulants correctly, and be proficient in harrowing skills. \x0d\\x0d\ According to different requirements of bean products, the temperature and concentration of soybean milk during solidification are different. For example, the temperature of tofu is controlled at about 80℃ and the concentration is11~12 (measured at 20℃ for milk juice). The temperature of semi-dehydrated bean products is controlled between 85 ~ 90℃ and the concentration is 9 ~10; The temperature of oily tofu is about 70 ~ 75℃ and the concentration is 7 ~ 8. \x0d\\x0d\ The optimum pH value of coagulated soybean milk is 6.0 ~ 6.5. \x0d\\x0d\ In terms of specific operation, harrow first and then brine, and the brine flow is large first and then small. Raking should be tight first, then slow down, while raking, bittern will be poured, and brain flower will appear in the tank by 50%. Raking will slow down, and bittern flow will decrease accordingly. When 80% of the brain flowers appear, the brine is stopped. When the brain flowers swim slowly and sink, the density of the brain flowers is even and the harrowing is stopped. \x0d\\x0d\ bittern and rake stop actions should be steady to prevent cylinder rotation. After stopping harrowing, the brain flower gradually sinks, drenched with brine, and there is no trace of spots, such as tender brain and thin pulp. If the brain is tender, it should be harrowed in time. To prevent squeezing and sticking to the bag, after stopping harrowing, pour some bittern on the brain surface, and if there are spots, it is a point. Let the brain rest for 20 ~ 25 minutes and squat down. \x0d\\x0d\7. Forming. After crouching, open the cylinder, put the pulp on and press it. When opening the cylinder, use the upper press spoon to put the brain slices in the cylinder to the front end of the cylinder, and withdraw the yellow pulp water. Normal yellow serofluid should be clear and light yellow, indicating that the brain is moderate, not old or tender. Yellow serofluid is dark yellow for brain aging, dark red for over aging, yellow serofluid is milky white and turbid for brain tenderness. In this case, measures should be taken in time, or bittern should be added or the tank (slurry) should be opened. \ x0d \ x0d \ Before pressing, straighten the bottom plate and the pressing die, wash the cooked cloth, wring it dry and smooth it, press the edges and corners, withdraw the yellow pulp water, and press it in different ways according to the age of the brain. Generally, it is divided into layers, light, fast and fast, lying on the spoon with the brain old, pulling the spoon with the brain tender, or digging the pit. Use high-quality brain pavement first, and then use ordinary brain, which not only ensures the smooth surface of the product, but also prevents the bag from sticking. The four corners should be fully leveled, the quantity should be accurate, the movement should be steady and fast, and the package should be tightly packed to avoid brain scattering, so that the brain in the cylinder is stable and unbroken. \ x0d \ x0d \ The pressing time is15 ~ 20min, and the pressure weight is about 60kg when two plates are pressed together. \x0d\\x0d\ Tofu is pressed immediately after pressing, and a well-scrubbed board sleeve is used, so that the board can be turned quickly, the board should be put lightly, the bag should be uncovered stably, the cover should be accurate, the movement should be strict, and the stacking should be slow. At first, spread the bottom of the stack more, and then press it separately, and each stack should not exceed 10 board, and in summer it should not exceed 8 boards. \ x0d \ x0d \ In the whole process of making tofu, strictly abide by the "30%" operation method, that is, point (brain), squat (brain), press (squeeze), and don't be greedy for quick results. Under normal circumstances, each person operates 6 plates to press the membrane, and 4 brain tanks are prepared. Three tanks have brains (each tank has a capacity of 4 plates), and the thickness of the products is consistent, which meets the requirements of commercial standards.