Propylene Glycol (PG) USP is a pharmaceutical grade of Mono-Propylene Glycols (PG or MPG) with a specified purity greater than 99.9%.
This food grade glycol is used as a heat transfer liquid in beer dispensing systems and temprite chillers. Using a mix of glycol and water will allow your cooling fluid to go sub-zero allowing icy cold beer and a frosty font. Glycol mixes are also used in jacketed stainless conical fermenters.
Propylene glycol is also used in a variety of other applications such as anti-freeze, cosmetics, food manufacturing / processing systems, VAC applications, laser cutting, milk & wine production equipment.