Aluminum beverage cans contain thin polymeric interior coating (referred to as “lacquer,” “varnish,” or “liner”) to prevent direct contact between the metal and beverage. These liners are effective barriers for most beers, but certain styles (like some sour beers) are reported to have excessive corrosion under ordinary storage conditions.

What components of beers accelerate corrosion and why? What concentrations of these corrosive components are tolerable, and are they synergistic? How much does liner selection matter, and why aren’t liners always effective? Results from recent work with accelerated and long-term storage trials at Cornell University will be shared.

Learning Objectives:

• Understand the anatomy of a beverage can and proposed major mechanisms for corrosion Explore the relative importance of components implicated in beverage can corrosion (pH, lactic acid, acetic acid, chloride, ethanol, copper, sulfur dioxide) Learn about the effect of other variables on corrosion (storage time, storage temperature, liner selection) Hear general recommendations for assessing corrosion risk in a beer