Determination of antioxidant capacity and molecular structure properties of koumiss

Koumiss is a traditional fermented milk product produced by the simultaneous fermentation

of mare's milk with lactic acid bacteria and yeasts, and it stands out for its functional

properties and potential health benefits. This study aimed to characterize the molecular

profiles of koumiss samples offered for sale in the Turkish market using FTIR spectroscopy

and to determine their antioxidant capacities using FRAP and CUPRAC methods. According

to the spectrophotometric analysis results, the FRAP values of the samples ranged from

0.3804 to 0.4650 mmol TE/L, while the CUPRAC values ranged from 0.2375 to 0.3039 mmol

TE/L. Sample K2 exhibited the lowest antioxidant activity in both analytical methods, while

sample K3 showed the highest FRAP value, and sample K1 showed the highest CUPRAC

value. FTIR spectroscopy analyses confirmed the molecular profile of the products at the

characteristic bond level; weak C-H peaks observed in the spectra in the 2900-3000 cm⁻¹

range reflected the low fat content characteristic of mare's milk, while characteristic bands in

the 1045, 1131 and 1459 cm⁻¹ regions confirmed lactose degradation, lactic acid formation

and ethanol production, revealing the fermentation maturity of the product. These findings

indicated that the structural and functional differences among the koumiss samples stem from

raw material characteristics, fermentation parameters, and microbial flora diversity. As a

result of the findings obtained; it has been revealed that the co-fermentation dynamics of yeast

and lactic acid bacteria directly determine the product matrix and that it is necessary to

optimize the raw material selection and process parameters for the production of koumiss with

standard quality and high functional bioactivity.