manufacturing method
1. raw materials. When using cold-pressed bean cake to make tofu, the temperature of soybean oil should not exceed 40℃. If the temperature is too high, although oil droplets are easy to gather and flow out, the protein water solubility of soybean is reduced or lost, so that soybean milk and tofu can't be made. When the temperature is too high (for example, above 60℃), bean cakes are easy to deteriorate during storage and transportation. Therefore, it is required that the oil yield of cold-pressed bean cakes for making tofu should not exceed 8% (referring to soybeans with oil content 16%), the storage temperature should be low, the storage time should be short, the storage capacity should not be too much, and it should be palletized to facilitate ventilation and cooling.
2. Crushing: Crush the bean cake into particles of about 8 mm with a crusher.
3. soaking: it is best to use cold water, and the pH value is 6.8~7.0. Soak at 27℃ for 4-6 hours in summer, 65,438+00-65,438+05℃ for 65,438+02 hours in winter and 8-65,438+00 hours in spring and autumn. When soaking, pour water first, then pour material, and stir while pouring material. After the bean cake is soaked, it is white inside and outside, and milky white is better. The ratio of bean cake to water is about 1∶6.
4. Upper grinding: Before grinding, it is calculated as 100 kg bean cake. In addition to soaking water, about 200 kg of water (three times of slag flushing water) is stirred evenly and ground, and the ground paste is filtered to about 100 kg of secondary slurry water. The concentration of grinding paste should be thin and sticky, dry and thin. Too much water will make the grinding paste thinner and easy to fall off, and too little grinding paste will dry.
5. Filtering: firstly, it is used to shake bags, and it must be filtered by three-ply woven tofu cloth with warp and weft density of 26×26. The soybean milk filtered once, twice and thrice is stored separately from the slag washing water for boiling. Then use a centrifuge, the first pass must be filtered with 80~ 100 mesh nylon yarn, and the second and third passes must be washed with 60 mesh nylon spinning cloth. Generally, it is required to wash the residue twice until the soybean milk clear soup is reached.
6. Boiling: Cook in a hot pot first, and brush the pot every time you cook (it is best to add some grease). Pour the slurry into a warm pot, first boil the light slurry with washed slag for three times, then pour the thick slurry twice and once (that is, add the slurry after boiling, and then add the slurry after boiling). When the soybean milk boils, use defoamer to clean the floating foam and take it out of the pot immediately. Every 20 kilograms of soybean cake raw material is about 150 kilograms of soybean milk to be cooked in 20 minutes. Then boil the pulp in a boiling pot. At the beginning, the air pressure should be sufficient. If the raw soybean milk is 0.5 tons, the time should not exceed 20 minutes. When the temperature reaches 97~ 100℃, boil the pot immediately. When boiling, make the soybean milk fluctuate up and down for three times, and open and close the valve for three times to eliminate floating foam. For the first time, the foam in the pot floated, and protein has not completely changed. The valve should be closed and opened after the foam sinks; When the foam floated for the second time, it burst and transparent body bubbles appeared. At this time, add an appropriate amount of defoamer to defoam, and close the valve at the same time; When the valve is opened for the third time, the foam dissipates rapidly and the soybean milk boils, which is 100℃. When the valve is closed, a small amount of residual gas will be discharged. Soymilk should be cooked fresh, not overstocked or stored.
7. Fine filtration: After the hot pot is cooked, it should be wrapped with fine tofu cloth with warp and weft density of 40×40 mesh (hand-rolled bag) and fine filtered. Cooking slurry produced by gas stove should be filtered with 100 mesh copper screen and vibrating screen to avoid mixing with bean dregs.
The future production method is the same as ordinary tofu.