Anthocyanin pigment stability of Cornus mas–Macrocarpa under treatment with pH and some organic acids

Abstract

The use of colors in food industry is essential for the creation of new products or their improvement. As an important pigment group, anthocyanin could be used as a natural coloring pigment in foods. This study aims at exploring strategies that result in color stability of anthocyanin in pear-shaped variety of blueberry (Cornus mas–Macrocarpa). In this study, the effects of different pH values (1, 2, 3, 4) as well as various concentrations (0, 120, 240, 480, 960 mg/L) of five copigments, including tannic, caffeic, benzoic, and coumaric acids, on anthocyanin copigment complexes (ratio 1:1) were investigated. The studied copigments were tannic, caffeic, benzoic, and coumaric acids. Anthocyanin was influenced by the highest concentration of 960 mg/L copigment in the presence of different pHs. Five groups were considered, one of which contained anthocyanin without copigment and the rest consisted of copigments. To evaluate the response of copigmentation through spectrophotometer, absorbance from samples was measured after 30 min of adding copigment to anthocyanin in the range of 450–600 nm wavelengths. The results showed that caffeic acid possessed the greatest anthocyanin stability compared to other copigments and it was the best copigment. An increase in the concentrations of copigments led to a higher level of anthocyanin stability and changes in hyperchromic and bathochromic. Moreover, the results revealed that the strongest hyperchromic effect for all organic acids was observed in pH 2, and the strongest bathochromic changes were observed in pH 4.

Attractive color is one of the most important sensory characteristics of fruit and berry products. Copigmentation can be a valuable, natural tool for improving the color of anthocyanin-rich food products, the color of which can be stabilized and enhanced by the addition of phenolic acids. The results showed that among four tested copigments (tannic, caffeic, benzoic and coumaric acids) caffeic acid was the best copigment. Also, the results obtained from this study on round sweet variety blueberry Cornus mas–Macrocarpa showed that the highest stability was obtained for anthocyanin-caffeic acid complex at pH 1.

from # All Medicine by Alexandros G. Sfakianakis via alkiviadis.1961 on Inoreader http://ift.tt/2mJD4tn