Functional properties of skim milk concentrates produced by reverse osmosis filtration and reconstituted commercial powders

Production of Sensorily Acceptable Pasta Filata Cheese with Partial Substitution of Sheep's Milk Powder in Different Forms

The presented study analyzed the possibility of pasta filata cheese production using sheep's milk powder in different forms and substitution amounts with fresh cow's milk. For the production of the pasta filata cheeses that were analyzed in the research, sheep's milk powder and reconstituted sheep's milk were used for partial substitution with fresh cow's milk in the amount of approx. 20, 30 and 40 percent (v/v). The obtained results showed that the more sheep's milk in the form of powder in the mixture, the lower the cheese's moisture content. The fat and protein content in the whey after the production of cheeses from mixtures was lower than after the production of cheeses from reconstituted sheep's milk only. Cheeses produced entirely from reconstituted sheep's milk displayed the highest fat loss. The greatest cheese yield was observed for cheeses from mixtures with sheep's milk powder and entirely from reconstituted sheep's milk. Pasta filata cheeses made from a mixture of cow's milk and sheep's milk powder that was not reconstituted were much less acceptable to consumers than reconstituted milk powder cheeses, especially those with 40% and 30% added powder. Sensory profile analysis showed that the addition of sheep's milk to the mixture, regardless of the form, affected the appearance, consistency, and flavor of the produced pasta filata cheeses. Mixing cow's milk with sheep's milk powder created the possibility of modeling the final cheese quality and yield.

Colloidal and Acid Gelling Properties of Mixed Milk and Pea Protein Suspensions

The present study aims to describe colloidal and acid gelling properties of mixed suspensions of pea and milk proteins. Mixed protein suspensions were prepared by adding pea protein isolate to rehydrated skimmed milk (3% w/w protein) to generate four mixed samples at 5, 7, 9, and 11% w/w total protein. Skimmed milk powder was also used to prepare four pure milk samples at the same protein concentrations. The samples were analyzed in regard to their pH, viscosity, color, percentage of sedimentable material, heat and ethanol stabilities, and acid gelling properties. Mixed suspensions were darker and presented higher pH, viscosity, and percentage of sedimentable material than milk samples. Heat and ethanol stabilities were similar for both systems and were reduced as a function of total protein concentration. Small oscillation rheology and induced syneresis data showed that the presence of pea proteins accelerated acid gel formation but weakened the final structure of the gels. In this context, the results found in the present work contributed to a better understanding of mixed dairy/plant protein functionalities and the development of new food products.