Comparison of Different Selective Media for the Recovery of Some Yeasts From Fruit Yoghurt (in English)

Abstract

In this study, different media used for the isolation of some yeasts from spiked fruit yoghurt samples were compared. For this purpose, as control medium; malt extract agar and five selective media were used. These selective media were malt extract yeast extract 50% fructose glucose agar, malt extract yeast extract 40% sucrose agar, malt extract yeast extract glucose 0.8% peptone agar, malt extract yeast extract glucose 0.1% peptone agar and potato dextrose 50% sucrose glucose agar. As yeast strains; Zygosaccharomyces rouxii IFO 0487, Zygosaccharomyces bailii IFO 0488 and Saccharomyces cerevisiae IFO 2359 were used. After suitable incubation periods, recovery performances of the media were determined. Based on statistical evaluation and some subjective parameters, malt extract yeast extract 40% sucrose agar was found superior for the tested strains.

Keywords

• Yeast, media, fruit yoghurt, recovery  

Seçici Özellikteki Farklı Besiyerlerinin bazı Mayaların Meyveli Yoğurttan Geri Kazanımları Amacı ile Karşılaştırılmaları (İngilizce)

Abstract

Bu çalışmada, yapay olarak aşılanan meyveli yoğurt örneklerinden bazı mayaların izolasyonu için kullanılabilecek farklı besiyerleri karşılaştırılmıştır. Bu amaçla, kontrol besiyeri olarak malt extract agar ve beş farklı seçici besiyeri kullanılmıştır. Bu besiyerleri; malt extract yeast extract %50 fructose glucose agar, malt extract yeast extract %40 sucrose agar, malt extract yeast extract glucose %0.8 peptone agar, malt extract yeast extract glucose %0.1 peptone agar and potato dextrose %50 sucrose glucose agar’dır. Maya suşları olarak; Zygosaccharomyces rouxii IFO 0487, Zygosaccharomyces bailii IFO 0488 ve Saccharomyces cerevisiae IFO 2359 kullanılmıştır. Uygun inkübasyon süreleri sonunda, besiyerlerinin geri kazanım özellikleri belirlenmiştir. Yapılan istatistiksel değerlendirmeler ve bazı öznel verilere göre, malt extract yeast extract %40 sucrose agar besiyerinin test edilen suşlar için daha iyi sonuç verdiği tespit edilmiştir.

Keywords

• Maya, besiyeri, meyveli yoğurt, geri kazanımMaya, besiyeri, meyveli yoğurt, geri kazanım

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