Process Optimization for Extraction of Polyphenols from Avocado Seeds (Persea americana Mill.) Using Response Surface Methodology

<jats:p>At the present time, polyphenolic compounds have attracted great interest due to their roles in the prevention of degenerative diseases and have used as the input material for manufacturing functional foods, nutraceutical and pharmaceutical products. Previous researches have revealed the avocado seed is rich source of polyphenolic compounds with antioxidant and antimicrobial activities; which they could be used as a source of potent natural ingredients and additives. In this study, extraction factors of polyphenols were optimized for recovery yield by using response surface methodology and the obtained polyphenol rich solution was encapsulated with different coating agents (Maltodextrin-MD and Gum Arabic-GA) as well as their mixtures. A Box-behnken design was used to investigate the effects of three independent variables including ethanol concentration (X1:35-65%, v/v), solvent to solid ratio (X2:8-12, v/w) and extraction time (X3:1.0-3.0 h). The result shown that the optimized extraction conditions were using ethanol concentration of 40% (v/v), ratio of solvent to solid at 12:1 and extraction time of 1.5 h. Under the conditions, the experimental recovery yield of polyphenols is 83.1% which is well matched with the predicted yield of 82.5%. Micro particle prepared by 20:80 of MD:GA ratio as coating agent can be selected for encapsulation of the polyphenolic compounds.</jats:p>