Akademik Veri Yönetim Sistemi
5th International Eurasian Conference on Biological and Chemical Sciences (EurasianBioChem 2022), Ankara, Türkiye, 23 - 25 Kasım 2022, ss.304
Drying is the process of removing water (dehydration) from solids in order to prevent microbial growth and chemical
reactions that may cause food spoilage. Convective drying, vacuum drying, freeze drying, and microwave drying are
among the most used methods for drying foods. In the drying of cultures containing live bacteria and yeast, it is important
that the bacteria and/or yeast in the culture can become active again and fulfill their functions after the drying process.
Kefir is a fermented dairy product with a slightly acidic/sour taste and distinctive aroma. It contains a special mixture of
microflora symbiotically contained in a carbohydrate polysaccharide matrix. It contributes positively to human health due
to its antimicrobial, antitumoral, antiviral, antimutagenic, and antioxidant effects. Kefir grains are starter cultures
containing various lactic acid bacteria, acetic acid bacteria, and yeasts used in kefir production. Besides the production of
kefir beverages, it is a valuable culture used in bread making, cheese production, ethanol production, and obtaining aroma
compounds. In this study, the kefir grains were dried at different microwave powers, and the effect of microwave output
power on drying, rehydration, and fermentation kinetics and biomass increase of kefir grains were examined. The results
showed that the drying times decrease significantly with the increase of microwave power. It was seen that the initial
drying rates are higher at high microwave powers and the drying process of kefir grains exhibits a decreasing rate of
drying period with the decrease of moisture content at all microwave powers. The highest biomass increase over the 10
days fermentation with 24 hours periods was obtained for the kefir grains dried at 100 W.