Development of functional yoghurt via soluble fiber fortification utilizing enzymatically hydrolyzed guar gum

The purpose of this research was to investigate the effect of enzymatically/partially hydrolyzed guar gum (PHGG) level (1–5%), culture level (1.5–3.5%) and incubation time (4–8 h) on functional and sensory property of yoghurt using response surface methodology. Central composite design was used to study the effect of processing variables on pH, viscosity, titratable acidity, water holding capacity and overall acceptability (OA) of yoghurt. The coefficients of determination for all the responses were greater than 0.8896 (except OA, 0.7833). Regression analysis showed that PHGG level was the most important factor that affected quality of yoghurt (p<0.01). Optimum value for PHGG level, culture level and incubation time obtained from response surface modeling were 2.02%, 2.33% and 5.28 h, respectively. Results revealed that partially hydrolyzed guar gum could be potentially used for soluble fiber enrichment of yoghurt with acceptable functional and sensory quality.