The effect of stevia and kiwi peel extract on the shelf life of sponge cake

These days, food consumers pay more attention to the quality and health of food and therefore there is a high demand for healthy and low-calorie food products, So in this study, the effect of stevia and kiwi peel extracts on the shelf life of sponge cake was investigated. Stevia extract was added to the sponge cake formulation at two levels of 0 and 0.6% and kiwi peel extract at four levels of 0, 0.5, 1 and 2%. The results showed that free fatty acid, peroxide value, and count of mold and yeast had an increasing trend over time so that different treatments on days 21 and 0 of the highest and lowest Mean free fatty acid (0.422, 0.204), peroxide value (2.48, 1.17) and logarithm of mold and yeast (6.17, 1.43) were respectively. Therefore, at the end of the period, the highest increase was observed in the control sample (T1) and the lowest increase was observed in the treatment containing 2% kiwi peel extract and 0.6% stevia extract (T8). The results of sponge cake pH showed that different treatments on days 0 and 21 had the highest and lowest mean pH, respectively. The results of organoleptic evaluation of general acceptance showed that treatments containing 1% and 2% kiwifruit peel extract (T3 and T4) had the highest score and treatments containing 0.6% stevia extract (T5) had the lowest overall acceptance score, respectively. Therefore, treatment with concentrations of 2% kiwi peel extract and 0.6% stevia extract (T8) could well increase the shelf life of sponge cake for 21 days compared to the control sample and was selected as the optimal treatment.