Orange sweet potato (Ipomoea batatas) puree improved physicochemical properties and sensory acceptance of brownies

Abstract

Daily fibre consumption among consumers is less than the recommended amount. Hence, fibre enrichment in desserts is proposed to increase fibre intake. The objective of the research was to study the effect of orange sweet potato (OSP) puree at different levels (0%, 25%, 50% and 75%) on physicochemical and sensory acceptance of brownies. Substitution of wheat flour with OSP puree in brownies formulations significantly increased total dietary fibre in the order: 75% OSP (6.41%) > 50% OSP (5.13%) > 25% OSP (3.24%) > 0% (1.70%). Additionally, moisture, fat, and specific volume were elevated with increased amount of OSP puree. Colour of brownies was affected with decrease of lightness (L∗), redness (a∗) and most prominently in yellowness (b∗). Hardness, adhesiveness, gumminess, cohesiveness and chewiness of brownies reduced significantly with incorporation of up to 50% OSP puree, but 75% OSP puree brownies was insignificant with 50% OSP puree brownies. Springiness and resilience had more prominent impact with increased amount of OSP puree. Sensory scores of appearance and colour of enriched fibre did not differ significantly with control brownies. However, texture, flavour and overall acceptability of the brownies were most preferred for 50% and 75% OSP puree substitution. The study suggests that OSP substitution at 50% and 75% are suitable to increase fibre in brownies with little effects on the appearance and were able to improve sensory attributes. Keywords: Orange sweet potato, Fibre enhancer, Textural properties, Sensory attributes