Development technologyof yogurt with coffee

Abstract

Formulations of yogurt flavored with coffee with a sugar content of 4 and 6 % and instant coffee Nescafe Gold in the amount of 0.5, 0.7 or 0.9 % were developed. The possibility of including in the formulation of low-fat yogurts protein enrichments, namely dry whey protein concentrate WPC 80 Milkiland in the amount of 1.5 %. A five-point scale has been developed to assess the organoleptic characteristics of new types of yogurt. It was found that the score of the consistency of the samples differed and decreased with increasing coffee content from 0.5 to 0.9 %. The sugar content did not affect the consistency, but higher taste scores were obtained with coffee-flavored samples with the addition of 5 % sugar compared to 4 %. Yogurts with 0.7 % coffee and 4 % sugar and both yogurts with 0.9 % coffee had the lowest scores compared to other yogurt samples. Changes in titratable acidity during yogurt fermentation and during storage were studied. It was found that the highest rate of increase of titratable acidity was registered for sample 3, which at 4 h of fermentation reached 98 °T compared to others, which is explained by the content of 2.2–4.5 % chlorogenic acid and other organic acids in instant coffee. It was found that lactic acid accumulated during storage of yogurts with coffee. On the first day of storage, its content ranged from 0.135–0.200 %, and on the 15th day increased to 1.22–1.42 %. Such changes are natural, because lactic acid is a product of lactic acid microflora metabolism during lactose fermentation. It was investigated that the active acidity at the end of fermentation was 4.56 units. pH against control – 4.72 units. pH and had a higher rate of decline compared to control. This can be explained by the mass fraction of lactose, which in the whey protein concentrate is 36 %. Also, this protein enrichment contains a large number of carboxyl groups, which increases the acidity of the clot and the finished product. All test samples were found to have better rheological properties due to the use of 1.5 % whey protein concentrate and sugar in the formulations. The parameters of technological operations in the production of yogurt with coffee are substantiated.