| Autor: |
Gursoy, Oguz, Kocatürk, Kübra, Yakalı, Hasne Nazlı, Yilmaz, Yusuf, Güler, Hande Özge |
| Předmět: |
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| Zdroj: |
International Joint Science Congress of Materials & Polymers; 2019, p77-77, 1p |
| Abstrakt: |
Kefir is one of the most preferred fermented beverages, and its production constitutes a significant portion of the dairy industry. In this study, the physicochemical and rheological properties of commercial (plain) kefir drinks were compared. Kefir drinks of different brands (n=5) were purchased from national markets in Turkey, and the samples with different expiration dates for each brand were used as replications. The ranges for the dry matter, protein and fat contents (%) of the commercial kefir drinks were 9.54-11.58, 1.55-3.08 and 2.50-3.34%, respectively. Moreover, the pH values of the samples were in the range of 3.80-4.11 while total titratable acidity (%) values ranged from 0.65 to 0.93% (lactic acid). Insignificant differences in pH values were determined among different brands of commercial kefir drinks (p>0.05) while significant changes were obtained among other physicochemical properties (p<0.05). In rheological analyses conducted at 4.0, 8.0 and 12.0±0.3°C, the power law model was used to interpret the rheological characteristics of kefir drinks, which resulted in higher R2 values. Besides, the apparent viscosity values of the samples (111.6-186.0 1/s) were observed to be inversely related to the temperature and varied between 0.97 and 124.50 mPa.s (p<0.05). Results showed that significant differences in the physicochemical and rheological properties were present among the commercial kefir samples of different brands and expiration dates, indicating the compositional variations of raw materials and kefir cultures used in the production. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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