Abstract

In the present study, the effect of microwave-assisted extraction conditions on the simultaneous recovery of pectin and phenolic compounds from sour cherry pomace (SCP) was optimized. The results showed that maximum yield of pectin (14.65 +/- 0.39) and phenolic compounds (14.36 +/- 0.29) was obtained under microwave power of 800 W, irradiation time of 300 s, pH of 1.00 and LSR of 20 v/w. The resulting pectin under the mentioned conditions had the moisture, ash and protein content, and also total carbohydrates of similar to 8.32, similar to 3.73, similar to 1.41 and similar to 26.43, respectively. Also, the obtained pectin with the molecular weight of 472.977 kDa and total phenol content of 91.54 +/- 2.92 mg GAE/g pectin had a high purity (galacturonic acid content of similar to 72.86) and suitable thermal stability (degradation temperature of 252.15 degrees C) and also could be classified as HMP (DE of 68.37 +/- 2.78). The FTIR, H-1 NMR and XRD analysis indicated that the obtained sample was rich in esterified poly-galacturonic acid and had an amorphous structure. The phenolic compounds analysis showed that the SCP extract had a concentration-dependent antioxidant effect that was comparable with ascorbic acid and BHA at high concentrations. (c) 2020 Elsevier B.V. All rights reserved.