Formulation and development of composite fruit peel powder incorporated fat and sugar-free probiotic set yogurt

Reduction of milk fat and added sugar makes the yogurt even healthier, yet texture deformations and less consumer acceptability will be attributed. Fiber incorporation may be counteracting these problems, which is tested in the present study by incorporating underutilize and cheap fiber sources. Composite fruit peel powder (FPP) formulated from industrial waste was incorporated into fat and added sugar-free set yogurts in three different proportions as 0.5%, 0.7% and 1% (w/v).  Yogurt without added FPP was considered as the control. Alteration of titrable acidity, pH and lactic acid bacteria viability were evaluated over a period of a month. Total soluble solids content (TSS), color values, texture profile, and consumer acceptability also were tested.  Results showed that FPP incorporation reduces the initial pH of the yogurt mix while increasing the TSS and impart color changes. The elevated amount of FPP mixture (0.7% and 1%) adversely affect texture parameters, microbial count and sensory acceptability. Firmness increased, syneresis decreased, and comparatively high lactic acid bacteria counts observed in fat and sugar-free yogurt with 0.5% FPP incorporation. No significant difference (p<0.05) of overall consumer acceptability among 0.5% FPP mixture added and control yogurts, which have the highest scores. Consumers preferred the bitter taste of that yogurt over the high acidic taste of control yogurt. Hence, 0.5% FPP mixture can be used to preserve the texture characteristics and increase the consumer acceptability of fat and sugar-free set yogurts.