The Effect of Use of Different Yeast Microorganism Species on Product Quality Parameters and Storage Life in Industrial Kefir Production
Project no. 21581 · Status: Kapanmış · 2020
Summary
<p>Kefir is a fermented dairy product that contains many lactic acid bacteria and different types of yeast. Yeasts in kefir culture are important in the formation of kefir's unique properties. Yeasts included in commercially marketed kefir cultures may be single or may consist of combinations of different species. Due to the CO2 produced as a result of the fermentation of yeasts, deformations and swellings occur in the packaging of the products, and this creates a problem because it is perceived as defective by the consumers. For this reason, some commercial starter cultures used in industrially produced kefir do not contain yeast. However, when yeasts are not involved in kefir production, the unique properties of kefir do not emerge. In this study, the effects of using different ratios of yeast microorganisms that cause or do not cause different swelling and deformity in industrial kefir production on product quality properties during the storage period will be examined. In this context, commercial kefir culture, which does not contain yeast, was combined with yeasts such as <em>Kluyveromyces marxianus, Debaryomyces hansenii, Kluyveromyces lactis, Saccharomyces bouardii, Saccharomyces cerevisia, Candida colliculosa, Yarrowia lipolytica, Geotricum candidum</em> and used in kefir production. Some physicochemical, rheological, microbiological, and sensory properties of these kefirs were examined during 28 days of storage. As a result of the study, it was determined that the use of different yeast species in the production of kefir drink affected the physicochemical, microbiological and some functional and sensory properties of the products.</p><p><strong>Keywords:</strong> Kefir, probiotic yeasts, rheological properties, sensory analysis, shelf life</p>