Acetic acid glacial food grade refers to a highly concentrated form of acetic acid that is used in the food industry as a food preservative, flavoring agent, and acidulant. The term glacial indicates that the acetic acid is in a concentrated form, with a purity of at least 99.5%. Acetic Acid Glacial Food Grade is a clear, colorless liquid that has a pungent odor and sour taste. It is naturally found in many foods, including fruits, vinegar, and fermented foods.