Development of riceberry cracker supplementation with unripe papaya flour

Abstract

The aim of this study was to investigate the effect of partial replacement of wheat flour with riceberry flour and unripe papaya flour on the physicochemical, functional properties and sensory evaluation of crackers. In the current study found that partial substitution of wheat flour with 5, 10, 15 and 20% riceberry flour (5, 10, 15 and 20%RBF) resulted in significantly increased in hardness and redness together with a decreased fracturability, lightness and yellowness of crackers. Researcher also found that substitution of wheat flour with riceberry flour resulted in an increase phenolic content from 2.03±0.36 (control cracker) to 8.78±0.19 (20%RBF) mg GAE/10g cracker and anthocyanin content from 153.45±14.77 (5%RBF) to 803.92±5.29 (20%RBF) µg C3G/10g cracker. Consequently, resulted in significantly increased antioxidant activity in riceberry crackers (P<0.05). Moreover, riceberry crackers 10, 15 and 20% formula had a lower glycemic index compared to the control cracker (P<0.05). Considering the microstructure of crackers, it was found that substitution of wheat flour with riceberry flour resulted in the surface of the crackers being rough and has a tightly packed internal structure. Therefore, resulted in a decrease in the preference score of hardness of 20%RBF. Surprisingly, cracker with 20%RBF had the highest overall preference score. In this study, it was found that cracker with 20%RBF had the highest antioxidant activity, overall acceptance score and had the lowest glycemic index. Hence, cracker with 20%RBF was chosen for partial substitution of wheat flour with 3, 5 and 7% unripe papaya flour (3, 5 and 7%UPF). The results found that the incorporation of unripe papaya flour into riceberry crackers resulted in significantly increased in fracturability, lightness, redness and yellowness together with a significantly decreased hardness when the proportion of unripe papaya flour increased in the crackers. The incorporation of unripe papaya flour into riceberry crackers resulted in an increase phenolic content from 8.61±0.20 (20%RBF) to 11.59±0.29 (20%RBF+7%UPF) mg GAE/10g cracker. Consequently, resulted in significantly increased antioxidant activity in riceberry crackers (P<0.05). Moreover, the incorporation of unripe papaya flour into riceberry crackers resulted in a decrease in the glycemic index from 60.10±0.34 (20%RBF) to 56.26±0.21 (20%RBF+7%UPF). Considering the microstructure of crackers, although the incorporation of unripe papaya flour into riceberry crackers resulted in the surface of the crackers being rough. Interestingly, the incorporation of unripe papaya flour into riceberry crackers reduced the compacted structure of the internal cracker product. When considering product preference scores, cracker with 20%RBF+5%UPF had the highest overall preference score. Therefore, the partial replacement of wheat flour with riceberry flour and unripe papaya flour enhances the antioxidant capacity and reduces the glycemic index of the product better than crackers that contain only riceberry flour. Consequently, increasing the value of waste materials and using of natural ingredients for product development in order to obtain nutritious crackers.