Summer is the best time of year to kick your feet up, lay back, and chill out with a tall, cold one. A summer without beer would be like Abbott without Costello...Gladys without the Pips. It just wouldn't be complete.
In spite of this basic truth, many home brewers pack it in for the summer and settle for the store-bought stuff. Maybe you're one of them. Why? Someone probably told you that you can't brew good summer beers, like lager and pilsener, during the summer months.
Or maybe you've tried, only to end up with off flavors, haziness, bottle gushers, or weak body and low head retention. These are the most common summer brewing problems. But these don't have to be YOUR summer brewing problems. Not if you learn a few simple summer brewing techniques.
Just heed the following summer brewing tips, and you too can enjoy a summer full of sun and fun...and the best cold beer on earth: yours.
Off flavors, usually described as "yeasty", may be caused by flash fermentation. This is a fermentation which occurs over a very short period of time, usually within twenty-four (24) hours. This is caused by a fermentation temperature which is too high, attributed to hot summer weather. Under these conditions, fermentation may take place so quickly that brewers are often unaware that the fermentation process has even begun. The formation of a "yeast cap" and a "hop ring" in the fermenter above the surface level of the beer are accurate indications that fermentation has been completed. A hydrometer reading will justify your suspicions.
Keep your fermenting beer in the coolest area of your home (a basement would be ideal). An area that maintains temperatures under 70 degrees is most desirable.
A refrigerator is an excellent way to control fermentation temperatures. However, a thermostat over-ride (item # TEM-EZ) will be necessary to maintain the recommended fermentation temperature of 55-65 degrees that most lager yeasts require. Otherwise, a slower, more extended fermentation will result.
Another way of brewing lager beer styles during the summer is to construct an air-conditioned chamber. The chamber can be simply a large cardboard box with the bottom cut out. Next, place the fermenter near an air-conditioner vent. Position the cardboard box over the fermenter and the air vent. Cut an exhaust vent into the cardboard box opposite from the air vent to allow the cool air to circulate around the fermenter before escaping. The chamber should remain 10-20 degrees cooler than the rest of the room, thus allowing you to ferment year round.
Fermenting at a consistent temperature is most important. Fluctuating temperatures in excess of 15-20 degrees could possibly lead to a stuck fermentation and tends to increase the possibility of off flavors.
One option with a two stage system is to ferment using the "blow off" method. Place a cold-water soaked bath towel around the shoulders of the carboy. The water then evaporates, cooling the warm wort as well as maintaining a more constant temperature.
Hot summer months may also contribute to the proliferation of wild yeast and bacteria. Visual signs include poor clarity and a "ring around the bottle" at the fill level. Physical characteristics of possible contamination include a bottle that gushes beer when opened, beer that lacks body and/or has low head retention, or a beer that is over-carbonated. The most telling characteristic is poor flavor. Flavor characteristics of a wild yeast or bacterial infection in your beer will include: Diacetyl - (a flavor sensation described as buttery or butterscotch); Dimethylsulfide - (a taste reminiscent of sweet corn or cooked cabbage); Phenolic - (a medicinal or plastic-like flavor); Sourness - (a flavor mostly perceived on the sides of the tongue).
While brewing during the summer months allows for the greatest exposure to wild yeasts and bacterial infections, these problems are not exclusive to the summer. These invisible, airborne contaminants are present year round and efforts to eliminate their exposure to your beer are simple!
Your home environment is a natural breeding ground for wild yeasts and bacteria and is impossible to sterilize. Therefore, we must sanitize everything that comes in contact with the wort after it has gone through the boiling process. Boiling, of course, kills bacteria.
Never use a wooden spoon because wood harbors bacteria.
Keep a cover, lid or cloth over the container of wort at all times, except during the boiling process. While the wort is cooling, prior to adding the yeast, and during the bottling process, it is imperative to protect it thoroughly.
Well water is another potential source of bacteria and should be boiled before use in making beer.
Make all-malt beers. Sugar beers do not mask off flavors as well because they tend to be lighter in body and flavor. Even all-malt beers may develop cidery flavor characteristics in a warm temperature ferment, in excess of 75 degrees.
If you have trouble controlling your environmental temperature, your best results will come from bottling the beer as soon as possible. Whether using the blow-off, two-stage, or single-stage method, nine (9) days is appropriate, with twelve (12) days being an absolute maximum in the fermenters. This should be a sufficient amount of time for complete fermentation and adequate clarity. The least recommended of the systems is the single stage, due to the large amount of head space above the surface of the beer.
Cool your hot wort to a temperature range of 75-80 degrees prior to pitching (adding) the yeast. If you don't have a wort chiller this can be achieved by setting your brewpot, containing 1-2 gallons of boiled wort, in a sink of ice water, rather than trying to cool the wort after it is brought up to the full 5-gallon level by the addition of tap water. The reasoning behind the desire for chilling the wort quickly is: potential bacteria starts more quickly at temperatures above 85 degrees, while yeast works well at cooler temperatures, which prevents bacteria from being able to develop because of the presence of the alcohol being produced.
If using liquid yeast, it is most important to make a yeast starter so that any lag time before the onset of fermentation is significantly reduced. The wort will remain at the highest levels of risk from bacteria until alcohol is present.
In general, stick to top fermenting ale yeast which is specially formulated to perform well at higher temperatures. Make ales and heavier, more robust beers such as porters and stouts. Ales can tolerate higher fermentation temperatures and tend to have more body in general. The characteristics of these styles tend to mask minor flaws and off flavors.
Lagers are best made in temperatures in the 55-65 degree range. They also tend to be lighter in hop bitterness and malt content and more delicate in character. Lager yeast tends to impart more off flavors at temperatures above 70 degrees, although these may yield adequate results at temperatures up to this level. Your loss will be a beer that is not quite as crisp and clean-tasting in most cases. However, the best time to make lagers if you don't have a controlled lagering environment (refrigerator) is in winter or spring. We have found that some of the crisp, clean characteristics of lagers fermented at higher temperatures can be salvaged when a 3-4 week lager stage at temperatures in the 35-45 degree is incorporated into the brewing process.
Be on guard for signs of yeast autolysis. "Listen to your beer", the yeast activity will tell you how things are going. Be assured that the yeast will remain active until all the fermentables are exhausted. When the activity of the yeast ceases, prepare to bottle the beer within 3-5 days. Yeast activity SHOULD NEVER resume again, ever. If it does, that could be a sign of a problem known as yeast autolysis, a false fermentation in which the yeast begins to consume other yeast cells. Its only by-product is off flavors.
If this is a possibility, immediately take a hydrometer reading and re-verify the reading 24-48 hours later. If there is no significant decrease in the specific gravity of the wort, our recommendation would be to bottle the beer as soon as possible. This activity may NOT diminish for months, possibly. The longer it is allowed to continue the worse the beer will taste. The autolysis will be neutralized under the pressure created by the carbonation process in the bottles. However, a beer that has been exposed to yeast autolysis will become a gusher in time, so enjoy it while you can, as soon as you can.
Make styles of beer that do not require extended bottle aging. Beer really needs cooler temperatures to benefit from advanced maturation. Aging at high temperatures can actually bring about a rapid onset of off flavors, so be prepared to drink beer made during the summer in a couple of months - not too difficult a task for most of us.
We hope this information will aid you in your quest for making good beer on a year-round basis. Keep in mind, while these suggestions are aimed specifically at brewing during the warmer months of summer, most of these ideas could be applied to brewing in any season.
The most important things to remember about brewing during the summer are:
1) sanitize everything that comes in contact with the wort/beer
2) prevent contamination by airborne wild yeast and bacteria
3) make all-malt ales at temperatures below 75 degrees
4) be on guard for signs of yeast autolysis
5) bottle in a maximum of 12 days
6) drink up!