Title : Investigation of whey protein-based side-streams as potential source of polar lipids-enriched dairy ingredients
Abstract:
The increasing global demand for dairy-based products, paediatric foods and trends in health and wellness, are driving the growth of high-protein whey-based ingredients, such as whey protein isolate (WPI). However, production of WPI from liquid cheese whey generates a significant amount of a lipid-enriched co-product, known as whey protein phospholipid concentrate (WPPC). While the commercial potential of this co-product is not fully realised, WPPC contains significant proportions of the major (e.g., β-lactoglobulin and α-lactalbumin) and minor (e.g., lactoferrin) whey proteins, in addition to other valuable nutrients such as milk fat globule membrane (MFGM) proteins and polar lipids (PL). Previous studies have shown that PL (phospho- and sphingo lipids) derived from the MFGM have unique bioactive properties and beneficial health effects, (e.g., lowering blood cholesterol levels, brain development, immunity and gut physiology). Moreover, WPPC’s techno-functional properties, (e.g., emulsifying properties and heat stability enhancement), make it interesting for use in numerous food applications, e.g., ice cream and bakery products. Nonetheless, WPPC’s potential is still poorly exploited and the majority of the existent PL-enriched products available commercially are predominantly extracted from buttermilk. Therefore, driven by the need of understanding how the feed-process-composition interplay, the PL and protein partitioning of a non-commercial WPPC during WPI manufacturing was studied and compared with a commercially available buttermilk powder (BMP). The protein profile was assessed by SDS-PAGE. The PL and fatty acid profiles were determined using HPLC with ELSD and GC with FID respectively. Results have shown, that the WPPC sample contains 5 times more total PL (including sphingomyelin) as percentage of total fat, and 5 and 7 time more β-lactoglobulin and lactoferrin, respectively, when compared with BMP. Therefore, WPPC may be considered as an added-value ingredient and a potential PL-enriched ingredient, for future use in the formulation of new nutraceutical and functional foods.
Acknowledgments: This project has received funding from the EI and from the European Union’s Horizon 2020 research and innovation programme under the Marie-Skłodowska Curie grant agreement No 713654.
