MICROBIOLOGICAL, CHEMICAL COMPOSITIONS AND ANTIOXIDANT CAPACITY OF TARHANA CHIPS FERMENTED WITH KEFIR

Abstract

In this study, the tarhana samples which fermented with kefir showed higher antioxidant activity than tarhana samples which fermented with yogurt (without kefir grains). The control tarhana chips (fermented with yogurt) samples (0.47±0.51 µmol/g TE) had significantly (P<0.05) lower antioxidant capacity (DPPH radical scavenging activity) than the fermented with kefir (0.67±0.02 µmol/g TE) samples. The ABTS values (0.83±0.28 µmol/ TE gr and 0.71±0.32 µmol/ TE gr) of extracts were significantly different in YT sample and KT samples fermented with kefir. The difference in antioxidant activities of traditional tarhana chips and tarhana with kefir grains was statistically significant (P<0.05). The analysis of total coliform group bacteria, total aerobic mesophilic bacteria, total Lactobacillus spp., and yeast-mould counts were conducted in samples. None of the samples contained coliform group bacteria. At the end of fermentation, count of Lactobacillus spp. and total aerobic mesophilic bacteria for traditional tarhana chips and fermented chips with kefir determined 8.47-8.94 log cfu/g and 7.43-7.95 log cfu/g, respectively. Yeast counts in the samples of chips fermented with kefir was found 6.89 log cfu/g. As a result, the use of kefir instead of yogurt in tarhana chips production is highly recommended as a tarhana type which has the potential to be a highly functional product with a high nutritional value due to its significant increase in antioxidant properties and its contribution to protein content.