원유와 무지방유로 제조한 케피어의 발효 및 저장 특성 연구 = A study on the fermentation and storage characteristics of kefir made from whole milk and fat-free milk

다국어 초록 (Multilingual Abstract)

Purpose: Kefir is a traditional acid-alcohol fermented milk that originated in the Caucasus region. It is rich in probiotics, such as lactic acid bacteria (LAB) and yeast, and has been studied for its antimicrobial, anticancer, and antioxidant properties. Methods: This study compared the physicochemical qualities and fermentation characteristics of kefir made from fat-free milk (0%) and whole milk (3.4%).
Results: Over two days of fermentation, both samples showed a significant increase in LAB cell counts over day one, with the LAB count remaining stable in fat-free milk kefir after refrigeration. Yeast counts showed no significant difference between the two samples after the first day (p>0.05). Similarly, there were no significant differences in the pH and sugar content between the samples.
Antioxidant capacity, measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, was higher in the whole milk kefir during fermentation and refrigeration compared to fat-free milk kefir. Particularly, 2,2′-azobis (2-amidinopropane) dihyhydrochloride (AAPH) radical scavenging ability of whole milk kefir fluctuated greatly, whereas fat-free milk kefir maintained relatively consistent values. Conclusion: Further research on the effects of fat content on the interaction between probiotics and the antioxidant components could enhance the health benefits of kefir. Consequently, fortifying the functionality of fat-free milk, kefir is expected to position it as a competitive product in the diet fermented milk market.