Every good experiment begins with a question. A chance conversation with a professional mead maker prompted this one. He was concerned about shelf stability and had looked into pasteurization. We talked about some of the research and anecdotal evidence. Pasteurization has been part of commercial-beer brewing for quite a while, and even some craft breweries are using it. Shelf stability is not typically an issue for homebrewers, but it might be helpful for wild beers. But how would it affect the beer?
Pasteurization Notes
Most of the online literature about beer pasteurization dates back to a 1955 study, which identified that American commercial breweries at the time applied 2.4 to 45.6 pasteurization units (PUs) to their beers, with an average of 14.8 PUs. Pasteurization units are used to rate pasteurization effectiveness; a single PU is equivalent to holding the beer at 60°C (140°F) for one minute. There’s a formula that maps time and temperature to PUs:
PU = t x 1.393 ^ (T - 60)