Spray drying of the prebiotic added kefir and determination of quality characteristics of the kefir powder and its reconstituted product

Besides their nutritional values, fermented dairy products are important food group due to their high digestibility and help in the protection of natural intestinal flora. One of these products, kefir, a probiotic fermented dairy product, is being consumed since ages and its consumption has been increased in the recent years due to the findings about its beneficial effects on human health. Kefir was produced using skim milk and industrial starter culture and inulin. Inulin was used as a supporter for the microbial flora. Two different carrier materials were added to kefir with three different ratio and in this way all the dryings had done on the mixture design. After all the analyses the most efficiency formula was defined as maltodextrine/Arabic gum %50/50, %0 inulin and 75°C outlet temperature of air. The results of microbial analyses had showed that lactic acid bacteria were more stable for the changing of production parameters. Yeast population was affected very much from the outlet temperature of air. If the temperature got higher, the yeast population would decrease. In this study firstly all the formula at the mixture design were produced and the analyses had done. After all the analyses were finished the formula was defined which had the highest efficiency and the highest alive microbial colony. And this formula reproduced for the storage. Storage had done for 90 days at two different temperatures; 4°C and 25°C. The formula of stored sample which was kefir without inulin dried with Arabic gum at 70°C. These samples were packaged with polyethylene under vacuum. During the storage period the samples were analysed at 1., 15., 30., 60. and 90. days. It was determined at end of the storage lactic acid bacteria has lived all 90 days but yeasts has died end of 90th day.