PREFILTRATION USING FORMED-IN-PLACE METALLIC MEMBRANES REDUCES MICROBIAL CONTENT OF WHEY

MEMBRANES were challenged with whey containing Lactococcus lactis ssp. lactis. Logarithmic reduction values (LRV) of lactococci and rejectio n of immunoglobulin G (IgG) were measured. Increasing lactococci from 10(7) to 10(9) did not affect IgG rejection. Of 20 membranes formed on conventional stainless steel substrates, none achieved 5 LRV and pass ed >50% IgG. Challenges of 20 DS-type altered substrates with 3mM phos phate buffer containing lactococci yielded 5.2 average LRV. DS-type su bstrates used to microfilter whey containing lactococci yielded 5.3 to 7.3 LRV and passed 66% to 77% of the IgG.