Brewing out in the cold can be tough, but we talked about how to stand up to that challenge. For some of you, that might never be your problem. In fact, in places like Texas or Florida, the wintertime is perfect for brewing. But in a few quick months, extremely nice turns into merely extreme.
It’s Not the Heat, It’s the...Yeah, It’s the Heat
Whether it’s the dry heat of the desert or swampland humidity, many brewers are forced to give up on the hobby for the summertime. Mashing and boiling are easy enough and outdoor brewing is arguably more pleasant than turning the kitchen into a sweat lodge. The tough nut is trying to chill the wort down and then keeping the fermentation cool enough.
Waiting For the Pitch
Waiting for hot wort to cool on its own takes forever, but when during a heat wave, even a wort chiller might not work. Keep in mind that a chiller is limited by the temperature differential between the wort and the water. Typically, it can cool the wort to within around 10°F (5.5°C) above the water coming in. If your tap is 80-90°F (27-32°C), you’ll never get into pitching range. That leaves three options: add ice or cold water, put the carboy in a refrigerated location, or use a dual stage chiller.
The latter is most efficient and best preserves the quality of your beer. Instead of a single coil heat exchanger, you’ll want two, connected by a hose. The first coil goes into an ice bath to cool down the incoming water, while the second goes into your wort, as usual. Cooler water coming in means cooler wort going out. The best optimization is to hold off on chilling the first coil for the first 15 minutes or so, while the wort is hottest. That will cut down on your ice and water usage.
The warmer your fermentation, the more active it is, but hot summers take it too far. On the one hand, bacteria get the same boost, and on the other, your benign brewer’s yeast is much more likely to produce solventy off flavors, like acetate esters and fusel alcohols. Taking extra care with sanitation is common sense, but your brewing choices can also impact how much the heat will harm.
Some yeast strains are more tolerant of warmer temperatures, which is why a saison might be a good summer brewing choice. You should also consider more forgiving beer styles, such as hoppier ales, where the stronger flavor can mask some of the flaws.
Sanitation and a less finicky yeast are good steps, but the best path is to find a way to keep your fermenter cool and collected. Some people just set the A/C for 70°F (21°C) and call it good enough. The downside is that the center of your carboy will always be hotter than the ambient temperature, so in most cases, you’ll want to go even cooler if you can.
If it’s not too humid, an inexpensive solution is to put the fermenter in a water bath and cover it with a t-shirt or towel to wick up moisture. Evaporative cooling will drop it below the ambient temperature. You can even kick it up a notch by blowing a fan on it.
The other alternative is to rely on refrigeration. At the cheap end, this can be done by placing your fermenter into an insulated box attached to a small fridge. For a little more money, you can upgrade to a regular refrigerator or chest freezer, but you’ll either need to replace the thermostat or use a temperature controller to keep it from running too cold.
At the top end, you can always invest in a jacketed conical fermenter along with a glycol chiller. I’d love to have that flexibility, but the cost is significantly more than I can justify, given that I have a very effective chest freezer solution. Regardless of your budget, though, one of the above solutions will keep you in beer year round.
Don’t be beat by the heat!
Podcast Episode 21: New Belgium's Wood Cellar Director & Blender Lauren Limbach
Jamie is joined by American sour beer pioneer Lauren Limbach of New Belgium Brewing, and they talk about the evolution of New Belgium’s sour beer program, from the earliest days two decades ago to the advances in analytics and technical process today.