Özet:

The aim of this study is to determine the quality characteristics of kefir by developing different flavours in order to increase its consumption. Plum (10%) and molasses (7.5%) which are rich in phenolic contents are used to produce kefir in different flavours. Chemical analysis (pH, titratable acidity, dry matter and colour), microbial analysis (total microorganism, Lactobacillus spp, Lactococcus spp. and yeast counts), total antioxidant activity (by ORAC method), total amount of phenolic contents and sensorial properties of all kefir samples were carried out at the 1st, 7th and 14th days of storage. Consequently, the results of pH, titratable acidity and dry matter in the kefir samples were determined to change between the values 4.11-4.39; 0.22-0.30 and 11.9-17.02% respectively, during the storage. In the colour analysis, the redness colour parameter of the kefir sample produced using molasses was determined to be higher compared to the other kefir samples. At the first day of storage, the total antioxidant contents of the control group kefir, plum- added kefir and molasses-added kefir samples were determined as 13.30; 16.80 and 17.35 µmol ml-1; and the total phenolic contents as 945.70; 2535.8 and 2357.6 mg ml-1, respectively. Content of total microorganism in kefir samples varied between 8.91-9.80 log kob ml-1during the storage period. Lactobacillus spp. and Lactococcus spp. contents of kefir produced using molasses were determined to have the highest values with 9.11 and 9.91 log kob ml-1, respectively, at the first day. Yeast content of the plum kefir and the molasses kefir samples including sugar was detected to be higher than that of the controlled kefir sample. According to the results of the sensory analysis, the kefir produced with plum was approved the most by the panelists. As a result of this study, two alternative products with quite high total phenolic content and antioxidant activity were developed for consumers.

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