Studying the possibility of obtaining natural dye from secondary products of grapes and forest berries processing

The aim of the study is to investigate the possibility of obtaining a natural dye from secondary products of grape and wild berry processing. Objectives: to extract dyes under different conditions in the presence of different extractants: distilled water, 1 % hydrochloric acid solution, 2 % citric acid solution, 50 % ethyl alcohol, 2 % citric acid solution in 50 % ethyl alcohol; to study the effect of enzymatic heat treatment (at different extraction temperatures of 20 and 40 °C) on the degree of extraction of dyes. To analyze and evaluate the obtained data. The objects of the study were pulp obtained from 2 grape varieties (Cabernet Sauvignon and Rubin AZOS) and 2 types of wild berries (blueberries and lingonberries), as well as pectolytic and cellulase biocatalysts cellulase, pectinase, pectoferm and VIAZYM® EXTRACT PREMIUM. The determination of coloring agents was carried out by photometric analysis at a wavelength of 520 nm. The recalculation of the content of coloring agents was carried out by cyanidin-3-glucoside chloride for blueberries and lingonberries, by malvidin monoglycoside for grapes. The greatest amount of anthocyanin dyes was extracted from the pomace of Rubin AZOS grapes and the pulp of blueberries with a solution of citric acid dissolved in 50 % alcohol. Extraction of dyes from the pomace of blueberries and grapes of the same variety with a 1 % solution of hydrochloric acid allows extracting an amount of anthocyanins compa-rable to extraction with citric acid in 50 % alcohol, but the use of chemically pure hydrochloric acid encoun-ters difficulties in providing it to enterprises and requires additional precautions. The smallest amount of dyes (more than 2 times) is extracted from the pomace of Cabernet Sauvignon grapes in the presence of the same extractants. The use of enzyme preparations with a complex of activities made it possible to ex-tract coloring substances from secondary products of processing wild berries and pomace of Rubin grapes in quantities comparable to the results of extraction with citric acid in 50 % alcohol. The duration of pro-cessing (extraction) with enzyme preparations at a water module of 1:10 was 2.0–2.5 hours at a tempera-ture of 40 °C, which allows for a significant reduction in the duration of extraction of coloring agents from secondary products of berry raw material processing.