| Large quantities of whey are produced in manufacture of cheese.This co-product contains a lot of bioactivator.In the developed country, Nutrients in the whey are recycled and the whey emission is controlled by the membrane-technology. In our country, the cheese production was still at the initial stage because of the high-priced equipment and the immature technology and the overseas barrier..So the way of whey utilizing is especially important to solve this proplem such as the condition of the whey-trade and price of cheese.The experiment was designed to study whey (UF) membrane technology for processing and to obtain the technological parameter.On the other hand, this study search a way of the probiotic product development and provides a way to utilize whey. This experiment's findings are as follows:(1).The different performance between three kinds of membranes has appraised after ultrafiltration. The results showed that the average permeate flux of the stainless steel membrane and ceramic membrane. respectively is 37.98LMH and 20.1LMH; In the optimistic condition of organic membrane, TMP=0.4MPa, the temperature is 45℃, the average flux only is 21.33LMH.But the relative loss will be lower than other two kind of membranes, the protein retentate rate may reach as high as 98%. (2)Polymerization condition of theβ-lg can be changed by the adjust pH. The results of the SDS-PAGE test showed that: the content ofα-la andβ-lg has been changed by the ultrafiltration processing .The Cα-la/Cβ-lg of whey permeates which across the ceramic membrane: from 0.4 up to 1.3;With increasing of VCR,the Cα-la/Cβ-lg value has reduced in the whey permeates and has increased in the whey retentate, Maybe theβ-lg has formed the gelating in the membrane surface.(3). Through repeated experimented,chemical Alkaline cleaning liquid of the organic membrane had determined the organic membrane the Alkaline cleaning liquid includes 0.01% base-protease, 0.04% NaOH, 0.625% Sodium Hexametaphosphate, 0.1% SDS, 0.2% EDTA 4Na salt, 10ppmH2O2 or the 10ppmNaClO and deionized water;(4).The fermentation conditions is determined by the test ,the enzymolyed whey solution is as the culture medium of fermentation: The concentration of whey powder is 8g/L, 4% neutral prolease, the enzymolysis time is 3h, enzymolysis temperature is 45℃, the fermentation temperature is 37℃, the stirring rate is 45rpm, the anaerobic condition is 20%CO280% N2, the pressure is 0.8MPa in reactor; After observing, high-count of colony forming unit of B. longum was discovered in the culture medium of whey enzymolysis ,the count reached 8.9×108 cfu/ml;(5).After mixing cryoprotectants ,the biomass of B. longum obtained by centrifugation is protected against the damage of freezing-dry . The average survival rate of B. longum is 81.98%.The cryoprotectants consists of skim milk, glucose and sodium glutamate .The cryoprotectants can protect the cell against the damage of freezing-dry.
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