Planning to give a talk about beer flavors for Scott Kerkmans in Brewing Industry Operations Program at Metropolitan State University, Denver, Colorado next month, so I have been looking into how beer is made, and in particular have been interested in the flavors that result from the temperatures at which beer malts are kilned.

Beer malts —left: pale malt; top right: black malt; bottom right: crystal malt. Photo by Lufke, from Wikipedia.

These temperatures range from below 100ºC for pale malts to increasing temperatures above that for darker and darker malts, finally to around 200ºC for black malts. The resulting color goes from pale yellow to dark brown, and the flavors go from grassy and sweet, through nutty for kilning temperatures around boiling, to chocolate and coffee flavors at temperatures up to 200ºC. (BTW, makes me think of the effects of oxidation and heating on teas.)

If you look at the temperature scale below you'll notice that the temperature-sensitive TRP channels in your mouth are activated at temperatures that are about half the temperatures at which these malts are kilned: at lower temperatures the chemicals in the malts tend to activate TRPV3 (warm) and TRPM5 (sweet), while at higher temperatures the kilned malts activate TRPV1 (nutty to chocolate flavors).

Am fascinated by this observation, and eager to figure out what it means — stay tuned!