Draft:Star San

Star San is the brand name for an acidic no-rinse sanitizer used for the brewing of beer and other fermented alcoholic beverages. A popular choice in both the amateur and professional brewing communities, it is a registered trademark of Five Star Chemicals & Supply, LLC.

Star San's active ingredients include phosphoric acid and dodecylbenzenesulfonic acid.

History
Five Star Chemicals, based in Arvada, Colorado, was incorporated in 1994 and began producing Star San in the same year. The company produces other brewing-related chemical products in addition to Star San. In 2018, the company was acquired by PurposeBuilt Brands, Inc.

Mechanism of action
Star San, when diluted properly, has a pH of 3.5 or less. The acids kill most spoilage bacteria and yeast on surfaces it is applied to, via disruption of the cell membrane. It requires a contact time of at least a few minutes.

Star San does not need to be rinsed, as it is non-toxic, unlike other sanitizers such as bleach or rubbing alcohol. Typically, the majority of the sanitizer solution is poured out of the vessel before subsequent usage, and what little remains gets diluted to a tiny proportion of the total volume of the wort or must. In such small dilutions, there is no discernible flavor impact on the finished product.

Star San contains surfactants, which create a foaming action when mixed into solution. This helps it to penetrate difficult to reach nooks and crannies in brewing equipment with a smaller volume of actual sanitizing liquid. To illustrate this, the manufacturer penned a mantra, "Don't fear the foam," which is often also repeated in brewing and homebrewing communities.