GRAS是Generally Recognized as Safe(公认安全)的缩写,也是《美国联邦法规》第21卷中一个独特而重要的食品成分分类类别。我国有“新食品原料”这一概念,而美国则采用公认安全物质(GRAS)模式进行管理。GRAS在世界各地具有极高的认可度...GRAS是Generally Recognized as Safe(公认安全)的缩写,也是《美国联邦法规》第21卷中一个独特而重要的食品成分分类类别。我国有“新食品原料”这一概念,而美国则采用公认安全物质(GRAS)模式进行管理。GRAS在世界各地具有极高的认可度,既是国内审批新食品原料的重要参考,也是新食品原料获准进入国际市场的重要凭证。本文对GRAS产生的背景、定义、通报程序,以及几个关注点进行简要介绍,希望为食品企业,尤其是对美出口的外向型食品企业提供一定参考。展开更多
Wittig-Horner method for the synthesis of Vitamin A derivatives is improved:3-methyl-5-(2,6,6-trimethyl-1-cyclohexen-1-yl)-1,3(or 1,4)-pentadienyl phosphonate is reacted directly with C 5-aldehyde in synthesis and a d...Wittig-Horner method for the synthesis of Vitamin A derivatives is improved:3-methyl-5-(2,6,6-trimethyl-1-cyclohexen-1-yl)-1,3(or 1,4)-pentadienyl phosphonate is reacted directly with C 5-aldehyde in synthesis and a double bond rearrangment step catalysted by base is curtailed.展开更多
文摘GRAS是Generally Recognized as Safe(公认安全)的缩写,也是《美国联邦法规》第21卷中一个独特而重要的食品成分分类类别。我国有“新食品原料”这一概念,而美国则采用公认安全物质(GRAS)模式进行管理。GRAS在世界各地具有极高的认可度,既是国内审批新食品原料的重要参考,也是新食品原料获准进入国际市场的重要凭证。本文对GRAS产生的背景、定义、通报程序,以及几个关注点进行简要介绍,希望为食品企业,尤其是对美出口的外向型食品企业提供一定参考。
文摘Wittig-Horner method for the synthesis of Vitamin A derivatives is improved:3-methyl-5-(2,6,6-trimethyl-1-cyclohexen-1-yl)-1,3(or 1,4)-pentadienyl phosphonate is reacted directly with C 5-aldehyde in synthesis and a double bond rearrangment step catalysted by base is curtailed.
