Detection of Extracellular Lipases and Genotypic Identification from Yeast Causing Spoilage of Some Dairy Products Produced in Gaziantep

Abstract

Yeasts are usually found in high amounts in dairy products, which show their ability to adapt to substrates rich in protein, lipid. sugar and organic acids. A wide distribution of yeast in dairy products is a result of proteolytic and lipolytic is activities. Spoilage yeasts and molds can grow in most. processed and raw limits. where environmental conditions are not suitable for most bacteria (low pH low water activity, aw). Nutrients and oxygen in food are the main factors that determine the type of fungal spoilage. In this study, dairy products samples (yoghurt, cream. butter, curd cheese. Antep cheese) were collected from local markets in Gaziantep province. In our study, a total of 20 yeast strains were isolated from dairy products and investigated for lipase activities in solid media containing tributyrin. Twenty yeast isolates identified by amplification and sequencing of the ITS region using ITS1 and ITS4 primers Yeasts were identified as Kluyveromyces marxianus (8 isolates), Candida intermedia (8 isolates), Pichia fermentans (2 isolates), Yarrowia lipolytica (1 isolate), Kluyveromyces lactis (1 isolate).