Preparation and characterization of a milk polar lipids enriched ingredient from fresh industrial liquid butterserum
Résumé
interesting nutritional and functional properties. This is mainly due to technological difficulties for their concentration and purification from by-products of the dairy industry. The objective of this study was to develop a technological process able to provide a milk PLs enriched ingredient from industrial fresh liquid butterserum, with possibilities to valorize the by-products. The process comprised the following successive steps: skimming, heat treatment, acid precipitation of caseins, concentration and purification of whey butterserum by ultrafiltration and diafiltration. The proposed process yields to a recovery of 62% of PLs present in the initial butterserum. The
final ingredient contained 31.5 ± 1.5 and 46.9 ± 2.2 % of PLs on dry matter and fat contents basis, respectively. The proportions of the different PLs found in the final product were 7.2, 8.4, 20.9, 26.8 and 36.5 % for phosphatidylinositol, phosphatidylserine, phosphatidylethanolamine, phosphatidylcholine and sphingomyelin, respectively. This fraction contained also proteins and triacylglycerols (about 26 and 34 % on a dry matter basis).The identified proteins were the 4caseins, whey proteins (α-lactalbumin, b-lactoglobulin, serum abumin, lactotransferrin) and 9 proteins from the milk fat globule membrane. This process will allow the preparation of milk
PLs rich ingredient for food applications.