Gras Claudia C, Bogner Hanna, Carle Reinhold, Schweiggert Ralf M
University of Hohenheim, Institute of Food Science and Biotechnology, Chair of Plant Foodstuff Technology and Analysis, Garbenstrasse 25, D-70599 Stuttgart, Germany.
University of Hohenheim, Institute of Food Science and Biotechnology, Chair of Plant Foodstuff Technology and Analysis, Garbenstrasse 25, D-70599 Stuttgart, Germany; King Abdulaziz University, Faculty of Science, Biological Science Department, P.O. Box 80257, Jeddah 21589, Saudi Arabia.
Food Res Int. 2016 Jul;85:291-300. doi: 10.1016/j.foodres.2016.05.006. Epub 2016 May 11.
This work aimed at studying the color intensity and stability of black carrot anthocyanins as influenced by intermolecular co-pigmentation. For this purpose, purified anthocyanin solutions were supplemented with purified genuine black carrot phenolics, chlorogenic acid, and an aqueous phenolic-rich green coffee bean extract at various anthocyanin:co-pigment ratios (1:0-1:162; pH 3.6). The hyperchromic co-pigmentation effect depended on the concentration of added co-pigments, resulting in an absorbance increase of up to 22% at the absorption maximum. Anthocyanin stability during heating (90°C, 5h) was barely improved unless the concentrations of co-pigments exceeded those of their natural source. When adding co-pigments at ratios above 1:9.4, anthocyanin heat stability was significantly improved. As acylated anthocyanins were most stable, breeders might aim at increasing their content in the future, while breeding for high levels of colorless polyphenols may be unreachable. Nevertheless, we provided proof-of-concept for the successful color enhancement by the addition of a phenolic-rich green coffee bean extract, being useful for food-grade applications.
本研究旨在探讨分子间共色素沉着对黑胡萝卜花青素颜色强度和稳定性的影响。为此，在不同的花青素与共色素比例（1:0 - 1:162；pH 3.6）下，向纯化的花青素溶液中添加纯化的真正黑胡萝卜酚类物质、绿原酸以及富含酚类的水相绿咖啡豆提取物。增色共色素沉着效应取决于添加的共色素浓度，在最大吸收波长处吸光度增加高达22%。除非共色素浓度超过其天然来源的浓度，否则加热（90°C，5小时）期间花青素的稳定性几乎没有改善。当以高于1:9.4的比例添加共色素时，花青素的热稳定性显著提高。由于酰化花青素最稳定，育种者未来可能旨在提高其含量，而培育高含量无色多酚可能无法实现。尽管如此，我们通过添加富含酚类的绿咖啡豆提取物成功增强颜色提供了概念验证，这对食品级应用很有用。
