Optimization of extraction condition of hesperetin in mandarin peel by acid hydrolysis

Acid hydrolysis is a favorable food processing for fruit peel to release deglycosylated compounds from tissues and enhance biological activity. This study aimed to investigate the optimal extraction of flavonoid hesperetin by acid hydrolysis in mandarin peel using response surface methodology (RSM). A Box-Behnken design was employed to develop the following three extracting parameters: ethanol concentration (X1: 60-100%), HCl molar concentration (X2: 0-1 M), and extraction time (X3: 4-8 h). The optimum extraction conditions for hesperetin were obtained at X1=100%, X2=0.6 M, and X3=4 h. The predicted results matched well with the experimental results obtained using the optimal conditions, which validated the RSM model with a good correlation. This study provides useful information on mandarin peel as a potential dietary supplement for functional ingredients.