Effects of novel autochthonous starter cultures on quality characteristics of yoghurt

Abstract

In the study, in order to develop novel starter cultures, three types of yoghurt were produced with different combinations of autochthonous yoghurt bacteria and the samples were investigated in terms of fermentation, microbiological quality, physicochemical properties (pH, acidity, water-holding capacity, apparent viscosities, and rheological properties), organic and benzoic acid contents, and sensory properties during 28 days. Lactobacillus delbrueckii subsp. bulgaricus content of all samples was between 7.29 and 8.58, and Streptococcus thermophilus content was between 8.03 and 9.02 log CFU/g during storage. Yoghurt type and storage time statistically affected pH, acidity, water-holding capacity, apparent viscosity, rheological properties, organic and benzoic acid content, and some sensory parameters. The general acceptability scores of the probiotic, traditional, exopolysaccharide, and control samples during storage were 8.27, 7.82, 7.53, and 7.47 respectively. Moreover, the results revealed that the strain combinations for probiotic, traditional, and exopolysaccharide yoghurt samples can be used as novel starter cultures for yoghurt production.