QUALITY ATTRIBUTES OF CONCENTRATED YOGURT (LABNEH) OF GOATS’ MILK FORMULATED WITH WHEY PROTEIN POWDER DURING STORAGE

Abstract

Background: Whey is a by-product and a good source of milk proteins, lactose, some minerals such as calcium, and soluble vitamins, which make such a by-product, be considered as a source of valuable nutrients and act as a functional food. This study was carried out to investigate the quality attributes of concentrated yogurt (Labneh) made of goats’ milk and different concentrations of whey protein powder (WPP). Methods: Three different formulations were made by mixing goat milk with different concentrations of WPP (0, 5, and 10%) and stored for different periods (0, 10, and 21 days) at 4±1oC. Standard methods were applied to determine the Physico-chemical, microbiological, and sensory parameters of Labneh. Results: The addition of WPP caused an increase in yield, chemical composition especially protein content and total solids (TS) with the minor effect of the storage periods. The microbial load of labneh decreases with an increase in WPP concentration except for lactic acid bacteria but significantly (P ≤ 0.05) increased with the storage periods. The addition of WPP to goat milk improved organoleptic quality scores. Conclusion: The production of Labneh with both goats’ and WPP showed that this mixture is an interesting opportunity to have a product rich in nutrients and considered satisfactory by consumers