Influence of Frying Conditions and Wild Sage Seed Mucilage Coating on the Physical Properties and Oil Uptake of Zucchini Slices during Deep-Fat Frying

Application of gums-based edible coatings to food products before frying is a technique that can improve the nutritional quality and sensory parameters of fried products. In this study, the effect of wild sage seed mucilage (WSSM) concentration at three concentrations of 0.5, 1.0 and 1.5% as edible coatings and frying temperature at three degrees of 155°C, 170°C and 185°C on the oil uptake and color change kinetics of zucchini slices during frying process have been studied. The color indexes include a* (redness), b* (yellowness), L* (lightness), and color change intensity (ΔE) were used to calculate appearance changes of fried zucchini slices. WSSM Coating treatments decreased the oil uptake of fried zucchini slices about 21.80%. By increasing WSSM concentration from 0.0% to 1.5% significantly decreased the oil uptake of zucchini slices from 8.96% to 7% (P<0.05), while the moisture content of samples were increased from 83.97% to 86.18% with increasing gum concentration (P<0.05). The average ΔE index of fried zucchini slices increased from 30.45 to 65.63 with increasing frying temperature from 155°C to 185°C. The average surface change values of fried zucchini slices was 33.13% for the uncoated samples, in comparison 30.40%, 29.36%, and 27.97% were found for fried slices coated with 0.5, 1.0 and 1.5% WSSM, respectively. The best coating suspension and temperature frying for reducing the oil uptake of fried zucchini slices was 1.5% WSSM and 155°C, respectively.