Short communication: Decrease of lipid profiles in cow milk by ultra-high-temperature treatment but not by pasteurization

Abstract

Triglyceride (TG) and fatty acid profiles of raw (RM), pasteurized (PM, 85°C for 15 s), and indirect UHT-treated (UM, 135°C for 15 s) cow milk were investigated by a lipidomics approach. Ninety-four TG were identified and all were present at significantly lower concentrations in UM than in RM or PM, and free fatty acid contents were significantly higher in UM than in RM and PM, indicating that TG lipolysis occurred to a greater degree in UM than in RM and PM. In addition, UM contained significantly fewer unsaturated fatty acids (14 types) than those in RM and PM, including C14:1n-5, C15:1n-5, C16:1n-7, C17:1n-7, C18:1n9 cis, C18:2n-6 cis, C18:3n-3, C18:3n-6, C20:1, C20:2, C20:3n-6, C20:3n-3, C20:4n-6, and C20:5n-3. However, we detected no significant differences between RM and PM in these fatty acids. In conclusion, UHT treatment, but not pasteurization, caused loss of the nutritional quality and bioactivity of cow milk lipid profiles.