When tofu is processed, tofu is used as a coagulant to dot tofu, and it is difficult to make old tofu, which is quantitatively made into paste. Here's a simple way to introduce it: Place the boiled soy milk in a jar and place it in a quantitative plaster. After the soy milk is solidified into curd, half a scoop of cold water is poured gently onto it. If the cold water is completely supported on the bean curd, the tofu is not old or tender; if the cold water sinks (the bean curd is gutter-like), the tofu is tender and it should be stirred with a spoon for a few times and a little bit of plaster be added; if the plaster is added, Beancurd was egg soup, indicating that the bean curd was old and should be mixed with cold water in time. Source: China Food Industry Network Information Officer: Provided by Sun Fengqing, Chongqing Agricultural Information Center