This article is missing information about acid content (4.5/5.5% grades called B and K types [K型] in China; should be published in some product listing/images with the ingredients); other chemistry (aromatic compounds; look for GC-O studies); collective trademark (集体商标) and geographical protection (& standard GB/T 18623) status in China. Please expand the article to include this information. Further details may exist on the talk page.(April 2019)