Application of milk protein concentrates in preparation of reduced fat sour cream

Abstract

Introduction. It was shown the expediency of using protein-containing ingredients of dairy origin in the production of reduced fat sour cream. Materials and methods. The fermentation kinetic of sour cream mixes was determined by the changes in titrated acidity. The microstructure of sour milk clots was studied using a light microscope. Rheological characteristics of reduced fat sour cream were determined using a rotational viscometry. Results and discussion. The rational doses of milk-protein ingredients in reduced fat sour cream that prevent excessive acidity of milk cream during fermentation, structure and stabilize this product during 5 days of storage, are the following: skimmed milk powder, 1%, sodium caseinate, 0.5%, caseinate calcium, 0.75%, whey protein concentrate, 1%, hydrolyzed whey concentrate, 30%. According to the level of inhibition of the lactic acid fermentation, milk-protein concentrates in the specified quantities can be arranged in the following sequence: skimmed milk powder → whey protein concentrate → caseinate calcium → hydrolyzed whey concentrate → sodium caseinate. By microstructural analysis of reduced fat sour cream, it was determined that 1% whey protein concentrate ensures proper moisture binding in the sour milk clot and contributes to the formation of a delicate structure with finely dispersed cells, while the use of 30% hydrolyzed whey concentrate forms a more viscous consistency of the product due to the presence of monosaccharides in it, which have a higher adsorption capacity for free moisture. The greatest structuring ability of caseinates and the most significant influence of whey proteins on the thixotropic properties of the reduced fat sour cream have been proved. A comprehensive indicator of the quality of reduced fat sour cream with milk-protein concentrates was calculated. Samples with 1% whey protein concentrate and 30% hydrolyzed whey concentrate had the most attractive sensory indicators, and got the highest score. The chemical composition of reduced fat sour cream samples with whey proteins was studied. It was found that 1% of whey protein concentrate increases the biological value by 1.3%, while 30% of hydrolyzed whey concentrate decreases it by 3.5%. According to the research results, whey protein concentrate was classified as a biological enhancer with moderate technological properties, and hydrolyzed whey concentrate as an effective technological additive that imitates the quality indicators of an analogue with medium fat content of 18-20%. Conclusions. The technological advantages of using whey concentrates in the composition of reduced fat sour cream as multifunctional ingredients have been shown.