Study on optimization of the process of ultrasonic assisted extraction of proanthocyanidins in pomegranate seeds by response surface methodology

In this paper, thin-skinned rough of Anhui Huaiyuan pomegranate varieties was selected as raw materials to research proanthocyanidin extraction process in pomegranate seeds.Four factors such as extraction power, pH, solid-liquid ratio and extraction solvent concentration were selected based on single-factor tests.Response surface methodology of four factors and three levels was used to analyze significance and interaction of every factor according to the center combination (Box-Behnken) experimental design principles, and to optimize the extraction process of procyanidins in pomegranate seeds.The results showed that the optimum conditions for ultrasonic assisted extraction of procyanidins in pomegranate seed was power 125W, pH5.0, solid-liquid ratio 1∶33, ethanol concentration of 51%, and the extraction rate of proanthocyanidins was up to 4.40%, relative error of 0.23% under this extraction conditions.