Garden strawberries are a popular berry crop and a valuable raw material for the production of functional foods. The aim of this study was to evaluate the effect of freezing on the organoleptic, physicochemical, colorimetric, and microbiological properties of Festivalnaya strawberry variety as a food raw material to substantiate their use in food systems. A comparative quality analysis of fresh and quick-frozen berries was conducted using standard methods. High organoleptic characteristics were preserved after freezing, including berry integrity, distinct aroma, and harmonious flavor. Significant changes in physicochemical parameters were identified. A decrease in the mass fraction of soluble solids by 6.6% and total sugar content by 25.5%, with a simultaneous increase in the mass fraction of titratable acids by 6.7% and ash by 15.3% were identified. A multidirectional dynamics of biologically active compounds was noted. The vitamin C content increased by 25.0%, and the mass fraction of dietary fiber increased by 14.9%, while the amount of total phenolic compounds and anthocyanins decreased by 21.1% and 26.1%, respectively. Colorimetric analysis revealed a change in color. The values of the L*, a*, b*, and C* coordinates of the color space decreased significantly, which was objectively confirmed by a visually observable slight darkening, a decrease in the intensity of the red-yellow color and color saturation, while the red-orange color tone (Hо) did not change significantly. A significant improvement in microbiological parameters was found. The number of mesophilic aerobic and facultative anaerobic microorganisms decreased by 5.5 times, mold fungi by 27%, and yeast by 59%, with a complete absence of coliform bacteria and salmonella. It has been concluded that the freezing process produces a product suitable for use in food systems.

Vasilina S. Nechaeva, Olga V. Golub, Vera A. Petruk, Oleg K. Motovilov, Elena V. Borodai

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