Investigating the effect of resistant starch, polydextrose and biscuit improver on the textural and sensory characteristics of dairy-multigrain composite biscuits using response surface methodology

Consumer awareness towards functional products resulted in their rapid popularity in the last couple of decades. Studies were conducted to investigate the effects of resistant starch (RS), polydextrose (PD) and biscuit improver (combination of enzymes: alpha-amylase, protease, xylanase and hemicellulases) on textural and sensory parameters to develop fiber enriched reduced calorie dairy-multigrain composite biscuits. Based on response surface methodology, a biscuit model system was carried out with replacement of bakery shortening with PD as fat replacer (4.25-5.95% on product basis). RS and biscuit improver were tried at different levels to balance the texture of reduced fat biscuits, while simultaneously resistant starch also increases the dietary fiber content. The levels of RS and biscuit were tried at 11-22% and 0.04-0.15% on product basis respectively. The independent variables within the levels studied influenced the dependent variables: hardness (from 58.70 to 103.9 N), spread ratio (from 5.40 to 7.15) and colour (from 7.4 to 8.16) (on 9 point Hedonic scale). The current findings demonstrated that the formulated biscuits had 142.7% higher total dietary fiber, 35% lower fat and 28.25% lower calorie contents as compared to the control samples, but were similar in sensory and physical characteristics.