Unraveling the contribution of melanoidins to the antioxidant activity of coffee brews
Unraveling the contribution of melanoidins to the antioxidant activity of coffee brews
复制标题
DOI：
10.1021/jf048500p
复制
发表时间：
2005-03-09
影响因子：
6.1
通讯作者：
Morales, FJ
中科院分区：
文献类型：
--
作者：
Delgado-Andrade, C;Morales, FJ
由相同的绿色咖啡豆生产的速溶咖啡由一家公司以不同的烘焙程度（浅、中、深）供应。通过超滤（10 kDa）和随后的渗滤获得类黑精。在2 M NaCl中孵育过夜后，从类黑精中分离纯类黑精。利用2，2 '-偶氮二（2-脒基丙烷）二盐酸盐诱导的亚油酸在含水体系中氧化形成共轭二烯，测试速溶咖啡、类黑精和纯类黑精的抗氧化活性。不同焙烧程度的类黑精与纯类黑精之间无显著差异。因此，纯类黑精部分对类黑精总抗氧化活性的贡献显着较低。类黑精的抗氧化活性的50%以上是由于非共价连接到类黑精骨架的低分子量化合物。食品类黑精的整体抗氧化性能的一个新的概念进行了描述，其中螯合能力对低分子量的抗氧化剂化合物连接到这些化合物的稳定参与产品的保质期。
Instant coffees produced from the same green coffee beans were supplied from a company in different roasting degrees, light, medium, and dark. Melanoidins were obtained by ultrafiltration (10 kDa) and subsequent diafiltration. Pure melanoidins were isolated from melanoidins after overnight incubation in 2 M NaCl. The antioxidant activities of instant coffees, melanoidins, and pure melanoidins were tested using the conjugated diene formation from a 2,2'-azobis(2-amidinopropane) dihydrochloride-induced linoleic acid oxidation in an aqueous system. No significant differences were found between melanoidins and pure melanoidins with different roasting degrees. Therefore, the contribution of the pure melanoidin fraction to the total antioxidant activity of melanoidins was significantly lower. More than 50% of the antioxidant activity of melanoidins is due to low molecular weight compounds linked non-covalently to the melanoidin skeleton. A new concept of the overall antioxidant properties of food melanoidins is described, where chelating ability toward low molecular weight antioxidant compounds is connected to the stabilization of these compounds involved in the shelf life of the product.