Production method 1. Pick beans and peel them. It is advisable to choose soybeans with full particles and screen out dust and impurities. The selected soybeans are crushed and peeled with a peeler, and the skins are blown clean. Peeling is to ensure yellow and white, and improve the utilization rate and yield of protein.
2. soak beans. Soak peeled soybeans in clear water for 4-5 hours in spring and autumn and 7-8 hours in winter, depending on season and temperature. The ratio of water to beans is 1: 2.5. It is advisable to knead beans by hand to swell and harden, not to be soft.
3. Grinding and throwing pulp. Both stone mills and steel mills can be used for pulping. The water used for pulping to filtration is 1: 10 (1 kg beans, 10 kg water), and the pulp is made into juice. Filter with a dryer for 3 times, and the hand-squeezed bean dregs are loose and there is no slurry.
4. Boil and filter the pulp. After the pulp is dried, it flows into a container through a pipeline, is blown by steam, and is heated to 100 ~ 1 10℃. After the pulp is cooked, it flows into the sieve bed through the pipeline, and then it is filtered by 1 time to remove impurities and improve the quality.
5. Extract yuba. After filtering, the cooked pulp flows into the yuba pot and is heated to about 60 ~ 70℃ for about 10 ~ 15 minutes to form an oil film (oil skin). Gently cut the film from the middle with a special knife, divide it into two pieces, and extract them separately. When extracting, rotate it into a column by hand and hang it on a bamboo pole to form yuba.
6. Drying and packaging. Send the yuba hanging on the bamboo pole to the drying room and arrange it in order. The drying room temperature reaches 50 ~ 60℃, and after 4 ~ 7 hours, the surface of yuba is yellow-white, bright and transparent.