Chemical composition, protein profile and physicochemical properties of whey protein concentrate ingredients enriched in α-lactalbumin
Giovanni Barone, Cian Moloney, Jonathan O’Regan, Alan L. Kelly, James A. O’Mahony
Abstract
• α-lac enrichment level was influenced by technological approach used. • α-lac enrichment led to higher tryptophan levels in WPC ingredients. • Selective precipitation gave ingredient with heterogeneous protein profile. • Precipitation of α-lac approach led to co-enrichment of phospholipids. The objective of this study was to complete a comprehensive evaluation of the nutritional composition, physicochemical properties and protein profile of three different whey protein concentrate ingredients enriched in α-lactalbumin (LAC). The LAC ingredients studied were manufactured using different enrichment approaches, namely membrane filtration (LAC-M), selective precipitation (LAC-P) and ion exchange (LAC-IE), and were compared to benchmark whey protein concentrate (WPC) and skim milk powder (SMP) ingredients with unaltered protein profile. The LAC ingredients had heterogeneous chemical composition and protein profile, which depended on the enrichment approach used. Protein profile of LAC ingredients was dominant in α-lactalbumin and therefore higher in tryptophan when compared to the benchmark ingredients. Unlike LAC-M and LAC-IE, LAC-P had a very complex protein profile. The new information provided by this study for these novel added-value whey protein ingredients will support the development of next-generation dairy-based formulated nutritional products.