Physicochemical and sensory quality of yogurt incorporated with pectin from peel of Citrus sinensis.

Industrial by-product like orange peel plays an important role in pectin manufacture. The objective of this article was to extract pectin from peel of Citrus sinensis and to study the effect of its incorporation on the quality of yogurt during the period of fermentation and postacidification. Physicochemical, organoleptic, and rheological properties of yogurt prepared with pectin were studied in order to determine the best preparation depending on the rate of pectin. The extraction pectin yield was estimated to more than 24%. The viscosity and acidity were increased with increasing of the pectin rate. The best viscosity value was obtained with 0.6% of pectin. Furthermore, the effect of the rate of pectin incorporation in the fermented milks was clearly observed on the number of Streptococcus thermophilus and Lactobacillus bulgaricus, the cohesiveness, the adhesiveness, the taste, and the whey exudation.