Effect of different stabilizers on quality characteristicts of set-type yogurts

The aim of this study was to determine the effects of seven different stabilizers on some properties of set-type yogurt. Stabilizers used were sodium caseinate, gelatin, carrageenan, xanthan gum, guar gum, locust bean gum (LBG), native corn starch. For the control group, no stabilizer was added. During the storage period, while the fat and pH values of the yoghurt samples were reduced, the stabilizers had no effects on the physical and chemical properties. The color values were affected by stabilizers and storage period at p<0.01 level. Stabilizers, except LBG, adversely affected the development of bStreptococcus thermophilus but did not show the same effect on Lactobacillus delbrueckii subsp. bulgaricus. Control sample was the most favorite example in sensory evaluations. The microstructural properties of yogurt samples containing gelatine, xanthan gum, guar gum and locust bean gum were quite different as compared to the control sample. The results of this study indicate that sodium caseinate and gelatin were the most suitable stabilizers that could be used in the production of set yoghurt.

Key words: Yogurt, stabilizer, gum, physical and chemical properties, microstructure