A. Sibel Akalın

Influence of fortification with sodium–calcium caseinate and whey protein concentrate on microbiological, textural and sensory properties of set-type yoghurt

The effect of fortification of yoghurt with sodium–calcium caseinate (SCC) and whey protein concentrate (WPC) on some properties of set-type yoghurt were investigated. The addition of WPC enhanced the viability of Lactobacillus delbrueckii subsp. bulgaricus more than SCC. The highest firmness values were obtained from SCC-fortified yoghurts, whereas yoghurts fortified with WPC had the highest water-holding capacity during storage. The yoghurts fortified with 4% w/w SCC or 4% w/w WPC had the highest viscosity. Yoghurts fortified with 2% w/w SMP, SCC or WPC showed similar taste and overall acceptability scores; however, samples containing 4% w/w SCC or 4% w/w WPC had the lowest scores.

Liquid chromatographic determination of thiamin in dairy products

Concentrations of thiamin were determined in pasteurized and UHT-sterilized milks, yoghurt and kefir samples by high-performance liquid chromatography using a reversed-phase C-18 column connected to fluorescence detector. The linearity, recovery and reproducibility of the method were satisfactory. The thiamin content ranged from 0.305±0.02 to 0.252±0.03 mg/l in market milks. Yoghurt samples had higher concentration of thiamin (0.355±0.04 and 0.404±0.02 mg/l) than values found in market milks. The least thiamin content was found in kefir (0.175±0.03 mg/l) among the samples analyzed.