Investigation on the Sensory and Microbial Characteristics of Functional Yogurt Containing Bell Pepper Extract

The yoghurt fortification with bioactive-rich components is one of numerous approaches to prevent the diseases correlated with nutritional shortages. However, this method may alter product characteristics. Therefore, the aim of current research was to study the effect of bell pepper extract (BPE) with three different colors on the sensory and microbial properties of set yogurt. For yogurt preparation, 5% of concentrated BPE with the yellow, orange, or red colors were substituted with the milk used for yogurt production. Results showed that by using BPE in yogurt formulation, the count of starter bacteria increased meaningfully while for sensory attributes, except for yogurt texture and appearance, the scores of taste and color were significantly decreased (p<0.01). The mean viable counts of lactic acid bacteria (LAB) for control and  yogurt samples containing yellow, orange and red BPE were determined as  9.62, 10.09, 10.08 and 10.10 Log CFU/g, respectively. The time of storage also had significant impact on the yogurt properties and as the time of storage increased, the count of LAB and sensory scores reduced notably. Results revealed that although addition of BPE with different colors into the yogurt formulation led to inferior scores of sensory characteristics (taste and color), all the yogurts containing BPE had acceptable sensory scores (mean scores>7, i.e. good mark). Consequently, with respect to the healthy components of bell pepper extracts, a yogurt with appropriate functionality could be produced. Therefore, the use of BPE with different colors (particularly orang BPE) in production of functional yogurt is recommended.