Ascorbic Acid Influence on the Extraction Intensity of the Anthocyanin Pigment from Black Currant Berries and Its Stability

Abstract

The article considers the ascorbic acid effect on the extraction rate and stability of anthocyanin pigment exuded from black currant berries. The researchers treated defrosted and crushed black currant berries with 0.2–10.0 % solutions of ascorbic acid at temperatures of 20–90 °C for 5–150 minutes and 100 °C for 2.5 minutes, then filtered the solution out. They determined the color intensity of the solutions by the optical density using spectrophotometer SHIMADZU UV-1800 (Japan). To determine the anthocyanin pigment content, a man diluted samples with solvent system ethanol/water/hydrochloric acid (69/30/1) and measured their optical density at a wavelength of 540 nm. The authors calculate anthocyanins content in solutions using the formula and determine that the use of 0.2–1.0 % solution of ascorbic acid as an extractant leads to the extraction intensity increase of anthocyanin pigment from plant raw materials. Adding a 1.0 % ascorbic acid solution of to the system increases the extraction degree of anthocyanin pigment by 1.4 times. A further increase in the amount of ascorbic acid in the solution to 2.0–10.0 % leads to a slight increase in the extraction intensity of anthocyanin pigment. The most complete anthocyanin pigment is extracted from plant raw materials in the presence of ascorbic acid at exposure temperatures of 20-80 °C for 30 minutes and 100 °C for 2.5 minutes. An increase in the exposure time to 60-150 minutes leads to a drop in the extraction degree of anthocyanin pigment and a change in the solution color. The solution of the pigment color becomes brown.