It’s 200 degrees outside. In the shade. Humidity is a million percent. Inside, it’s 250 degrees. All the windows are open, but there’s no breeze and nightfall brings no relief. When you finally fall asleep, after flipping the pillow to the cool side for the hundredth time, the cicadas wake you up.
The Weather Channel says tomorrow will be another record breaker, and now you are stuck to your naugahyde Barcolounger.
Too hot to brew, right?
If you can peel yourself from the cheap chair and don’t mind standing over a pot of boiling brew, you can brew in the summer. All it takes is some good old-fashioned Yankee Homebrew Ingenuity and a little planning.
You have probably heard about the problems associated with too-warm beer fermentation: yeast run wild, infection leading to butter, and other nasties. Too-warm fermenting conditions can produce weird flavors in your beer, such as ethyl acetate (nail polish remover), fusel alcohols, and even rotten egg aromas. This is not a technical article, so we can skip the figures and equations. Suffice to say that if your ferment temperature is too high, your beer flavor may suffer.
Warm fermentation can also spur production of fusel alcohols and other compounds that can cause a blockbuster katzenjammer the morning after.
But armed with that knowledge, you can choose a brew that won’t mind the heat of the kitchen.
Choose the Right Brew
For summer brewing it’s best to shelve plans to make a light Czech pilsner or American lawnmower beer. The basic rule is by the time it’s hot enough for you to crave icy-cold light lager, it’s too late to make it.
It’s better to choose a gutsy ale, stout, or porter. These brews are more forgiving of esters and excess fruitiness spurred by the warm ferment. You should also choose a yeast strain that can handle the heat.
Assuming you have mastered the art of liquid yeast cultures, choose a forgiving strain of ale yeast. (See BYO’s premier edition if you need a brush-up on handling liquid yeast cultures).
Wyeast’s 1028 London Ale or 1968 Special London Ale are good choices. They will perform at higher temperatures and will leave a butterscotch note, completely appropriate in English ale. The same goes for BrewTek CL-160 British Draft Ale, Yeast Culture Kit A17, and Yeast Lab A03 London Ale. Wyeast 1056 American Chico and 1338 European Ale will also do well at higher temperatures.
If you crave the riot of diabolically complex flavors in Belgian beer, now is the time to experiment with an abbey, trappist, or white (wit) style. The heat will maximize production of fruit notes for which those styles are famous. Try any of BrewTek’s Belgian ale series, Wyeast 1214, Yeast Culture Kit A16, or Yeast Lab A08. For wit, try Wyeast 3944 or Yeast Culture Kit M01.
If you are using dry yeast, Cooper’s has gotten some good press for performing well at higher temps.
Chill Out, Carboy
So how do you keep that fermenting barrel cool when the rest of the house is about to burst into flames from the summer heat? As you can imagine, there are as many techniques as there are homebrewers.
About the lowest low-tech option (and the least expensive) is the old towel-around-the-carboy trick.
Everybody knows that as a liquid evaporates, its temperature drops. Why? Philadelphia refrigeration engineer Ike Ehrlich explained it this way: “Liquid evaporates in the presence of heat. But as it evaporates, it takes energy—in the form of heat—away from the surroundings. So the area very close to the evaporation will be cooler than the surrounding area.”
It’s why we get cold when we are wet. And why we sweat when it’s hot. As the sweat evaporates, it uses this trick of nature to cool the surface of the body. You can use nature’s tricks to keep your beer cool, too.
You will need a basin, bathtub, or even your brewpot, if it’s big enough for your carboy to fit inside. Put a few inches of water in the basin, wrap the carboy in a big beach towel, place it in the basin, wet the towel, and let nature take its course. It helps to tie or rubber-band the towel in place around the neck of the carboy to keep it from slipping off.
The towel wicks the water up from the basin and it evaporates, lowering the temperature of your fermenting brew, depending on the relative humidity at the time.
That’s probably this system’s biggest limitation: If you live in a really muggy place, evaporation comes close to a standstill during the humid “dog days” of summer.
You can help it along, though. As homebrewer Rick Theiner of Memphis discovered, an electric fan will accentuate the effect of evaporation. “I put a box fan next to the whole setup with a timer switch. The fan runs for about four hours a day. The evaporation rate is increased, and the towel stays damp since the fan does not run all the time,” Theiner says.
The towel system is low maintenance. You need only to keep an eye on the water level during the fermentation.
The Icebox Method
Do you remember iceboxes? Or maybe you heard about them from your parents. Lots of folks still call the refrigerator an icebox. And the icebox was central to the life of Ralph and Alice Kramden (Norton was always foraging there).
In the old days everybody’s kitchen had a tightly insulated box with convenient compartments and doors. Every so often you bought a block of ice from the ice man and put it in the top compartment. This kept the food inside relatively cool.
Homebrewer and equipment designer Dan Listermann of Norwood, Ohio, employs a variation on the icebox theme. “We have a broken refrigerator, the kind the tenants defrosted with a sharp knife. This is my icebox. I freeze milk jugs filled three-quarters full of water in my good fridge and each day place a few inside the old fridge with the fermenter.
“I can depress the temperature up to 15° C (59° F). Perfect for ale in the summer, lager in the winter,” Listermann says.
He rotates the milk jugs, refreezing them as needed. He says the inside of the box gets rather damp, so he wipes it down with bleach solution every few days to prevent mildew.
If you don’t have a dead fridge, you could use a very large picnic cooler, standing on one end, or a wooden or cardboard box lined with Styrofoam as your icebox.
Stealing Cold Air
If you have air conditioning, either window units or central, another way to beat the heat is to route the cold air outflow to your fermenter before the air fills the room.
Jones Rutledge of Memphis uses this method: “I park the carboy as close as possible to the air conditioner. I made some cardboard deflectors to ensure the carboy gets plenty of cold air. This prevents having to run the AC full force, freezing everyone out.”
A High-Tech Chicken Coop
Fridge-techie Ehrlich says if you can get your hands on a small window air conditioner, you can build an air-conditioned “chicken-coop.”
“Stud it out, use plywood or paneling for the walls, and insulate every inch of the interior. Weather strip the door. Cut a hole and frame it out for the air conditioner, put on a pitched roof with some tar paper, and you’re in business,” he says.
Ehrlich uses a window AC unit to successfully cool to between 65 and 70° F. Lower than that and the unit’s coils will start to freeze. So don’t go this route if you have authentic lager in mind. But this idea is perfect for ale.
Going All the Way
If you really want to take control and thumb your nose at the summer heat, you will need a working refrigerator.
“What’s the problem?” asks Ed McNierney of Groton, Massachusetts. “My brew fridge stays 44° F, even in the middle of July!”
McNierney admits he would rather brew light lager in the summer instead of stocking up on it in the spring. “I just can’t seem to let good beer sit around for months, waiting for the right drinking season. I recommend getting the spare fridge, assuming you have someplace to put it.
“Mine came from a yard sale. A nearly new 21-cubic-foot box, with freezer, for $100. I ferment in the fridge section, store my hops and other goodies in the freezer section,” he says. In addition to yard sales, cheap fridges can be found at large apartment buildings because they often update their appliances.
Going the fridge route offers obvious advantages. You can brew whatever style you like whenever you like, without having to be concerned about overheated fermenters and fruit-salad aftertaste.
To really, really take control, you will need to invest in an external thermostat for your brew fridge. The thermostats installed in most refrigerators and freezers operate in a narrow range, around 35° to 45° F. Okay for lager but too cold for ale.
The best option here is the “plug ’n’ play” thermostat. You plug it into the electrical socket, then plug your fridge or freezer’s power cord into it. A temperature probe goes inside the box, and you simply set your desired temperature. Ready to rock ’n’ roll in 60 seconds. These run between $40 and $60 and are available at many well-equipped homebrew supply stores.
But as McNierney discovered, you might not need any help from an external device. “I don’t use any fancy auxiliary thermostat. I bought a $5 fridge thermometer from the kitchen store and fiddled with the temperature dials until I got it right. It’s good enough for me!” he explains.
So what are you waiting for? Scrape yourself from that Barcolounger and get brewing.