Investigation of the Physiochemical and Microbiological Quality of Fruit Yoghurt Sold in Elazig Province

Abstract

This study was conducted to determine some quality parameters of 25 fruit yoghurt samples (strawberry, forest fruit, blueberry, apricot, fig, mango, peach) sold in Elazig province. For this purpose, physicochemical (pH, acidity, fat, dry matter, starch, peroxidase, heat treatment) and microbiological [total mesophilic aerobic (TMA) bacteria, psychrotrophic bacteria, Lactobacillus-Leuconostoc-Pediococcus (LLP), lactic streptococcus, proteolytic and lipolytic microorganism, coliform, Enterobacteriaceae, Escherichia coli, Staphylococcus-Micrococcus, Staphylococcus aureus, Salmonella spp. and yeast-mold] analyzes of fruit yoghurt samples were performed. It was determined that 14 samples (8%) did not comply with the Turkish Food Codex Fermented Dairy Products Communiqué and TSE yoghurt standard regarding acidity value (% l.a.). The presence of starch in 91 (52%), peroxidase in 91 (52%) and heat treatment tests in 147 (84%) of the samples were positive. In the 161 (92%) samples coliform, Enterobacteriaceae and Staphylococcus-Micrococcus; and in the 154 (88%) of yeast and mold microorganisms were observed to be less than <1.0 log10 cfu/g of. Total psychrophilic bacteria, E. coli, Staphylococcus aureus, and Salmonella spp. have not emerged in any of these samples (<1.0 log10 cfu/g). There is only a statistical significance observed in Proteolytic bacteria between fruit yoghurt groups (P < 0.05). The lowest number (5.36 ± 0.10 log10 cfu/g) of proteolytic bacteria was observed in forest fruit; the highest (7.02 ± 0.52 log10 cfu/g) was determined in yoghurt with figs. As a result, it was concluded that the microbiological quality of the examined fruit yoghurt samples was not adequate for the hygienic conditions. It is thought that hygienic conditions were not considered during the production process and it could pose a risk to public health.