期刊
FOOD CHEMISTRY
卷 292, 期 -, 页码 217-226出版社
ELSEVIER SCI LTD
DOI: 10.1016/j.foodchem.2019.04.066
关键词
Milk gelation; Caseinomacropeptides; AprX; Psychrotrophic bacteria; Capillary zone electrophoresis
Heat-stable peptidases released in refrigerated raw milk by psychrotrophic bacteria are responsible for UHT milk gelation. K-casein-derived caseinomacropeptides, identified by mass spectrometry, were constantly detected in gelled milk by capillary electrophoresis. Strains of Pseudomonas fluorescens, Ps. poae and Chryseobacterium joostei, selected among aprX-positive strains from raw milk, were incubated in milk up to 6 days at 4 degrees C before sterilization (98 degrees C/4 min). Samples were then stored at 25 or 40 degrees C, visually observed for gelation, and analysed for presence of caseinomacropeptides throughout 90 days of storage. Depending on cold pre-incubation time, caseinomacropeptides accumulated well before gelation onset in milk stored at 25 degrees C. Caseinomacropeptides were successively degraded, especially in milk stored at 40 degrees C, due to extensive proteolysis, and an abundant sediment developed instead of a gel. The caseinomacropeptides are here presented as an early indicator of UHT milk gelation and a mechanism explaining this phenomenon is proposed.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据