Optimization of the extraction process of bioactive substances from cherry pomace

Every year juice processing plants produce tons of berry pomace containing a lot of useful substances. A huge place among them is occupied by polyphenolic substances with antioxidant properties. Extraction of substances with antioxidant properties from this raw material is a promising direction for the creation of functional ingredients for food products. The aim of the research is to establish the optimal parameters for the extraction of polyphenolic compounds from cherry berry pomace. A two-factor experiment was used to determine the optimal conditions for the extraction process. The dependent variables were the content of polyphenols and flavonoids, and the variable factors were the duration (from 10 to 50 min) and temperature of extraction (from 40 to 60°C). Extraction was carried out with a 50% ethanol solution. Before extraction, the experimental samples of pomace were subjected to enzymatic treatment with cellulase for 1 hour at a temperature of 50°C. The obtained extracts were analyzed for flavonoid content spectrophotometrically, as well as polyphenols using the Folin-Ciocalteu method. The results of the studies showed that for the most effective extraction of flavonoids, it is recommended to use an extraction temperature of 47.17°C, and the extraction period is 49.9 min. With these parameters, the predicted total flavonoid content in terms of rutin will be 5.22%. To achieve a polyphenol content of 1.21 mg equiv. of gallic acid, it is recommended to maintain the extraction temperature at 49.8°C with the extraction period of 38.1 min. The content of polyphenols in the extracts obtained according to the optimal parameters was 4.5% higher than the predicted value, and content of flavonoids was 5% lower. The content of bioflavonoids after enzymatic treatment of the pomace increased approximately 2 times, and polyphenols 1.4 times. Thus, mathematical modeling of the extraction process allows for quick and fairly accurate prediction of the optimal process parameters for obtaining extracts with a high content of bioactive substances. Preliminary enzymatic treatment of pomace allows for an increase in the yield of bioactive substances.