§ 173.50 Polyvinylpolypyrrolidone.
The food additive polyvinylpolypyrrolidone may be safely used in accordance with the following prescribed conditions:
（a） The additive is a homopolymer of purified vinylpyrrolidone catalytically produced under conditions producing polymerization and cross-linking such that an insoluble polymer is produced.
（b） The food additive is so processed that when the finished polymer is refluxed for 3 hours with water, 5 percent acetic acid, and 50 percent alcohol, no more than 50 parts per million of extractables is obtained with each solvent.
（c） It is used or intended for use as a clarifying agent in beverages and vinegar, followed by removal with filtration.
更多關于美國 FDA 可直接加入食品中的輔助性食品添加劑的種類法規，請點擊美國FDA 21 CFR 第173部分可直接加入食品中的輔助性食品添加劑種類匯總
