Characteristics of fermented ewe's milk product with an increased ratio of natural whey proteins to caseins

- New dairy product can be develop by using ewe's milk especially for production functional fermented beverages.
- Membrane separation is an interesting method for isolating bioactive compounds from milk.
- Native whey proteins as high biological value components can be used for functional fermented milk production.

The aim of the study was to produce fermented ewe's milk with an increased ratio of native whey proteins and to characterize selected properties (metabolic activity, mono- and disaccharides, lactic acid and ethanol content, aroma profile, texture, color and sensory properties) of experimental milk and final product. Increasing the ratio of whey proteins to caseins in experimental milk resulted in higher activity of microorganisms belonging to the starter culture used in fermentation and higher content of volatile ketones in total volatile compounds identified during experiment. Increase in the lactic acid content and brightness parameter in fermented milk was observed in product made from experimental milk with modified ratio of whey proteins to caseins. It was concluded that changing the ratio of the main protein fractions in experimental milk differences in the physical and chemical properties of the final product, but these changes did not have a negative influence on sensory properties and product desirability.