The effect of supercooling-freezing on inhibition of ice recrystallization during storage

摘要

In this paper, the effect of supercooling-freezing (freezing via supercooling) on ice crystalrecrystallization in tofu (soybean curd) during frozen storage was investigated. The ice crystal growthrate by recrystallization depends on the storage temperature; however, there is an assumption thatthe size of ice crystals influences the ice crystal growth rate, and the assumption was investigated.Using a conventional freezing method, the ice crystal size of surface and center of food tends to bedifferent. In contrast, supercooling-freezing is known to form minute and nearly uniform ice crystalsin food. Each sample was frozen by rapid freezing(R), supercooling-rapid freezing (SR), andsupercooling-slow freezing (SS) to observe the difference of ice crystals growth. The samples werepreserved for up to 1 month at several temperatures. From the X-ray CT images, characteristics ofice crystals were observed, and the growth rate of ice crystal was calculated for each freezingmethod.