Big Batch Brewing
Five gallons of beer just disappears too fast. You send a few bottles into competitions, give one to your neighbor here and your mailman there, have a poker game, and suddenly that great batch of homebrew is reduced to just a couple of bottles. It’s time to scale up your homebrew system. It’s easy to double or triple your batch size with a little extra equipment, and it takes about as long as brewing that five gallons did.
Whether you brew with grain or extract, you can effectively scale up your system. With extract you’ll need only a few extra pieces of equipment and you can even continue brewing on your stove top without a lot of additional mess. Grain brewers will probably need a little more equipment, more space, and more cleanup time. But you’ll be able to brew like the pros, and the savings of buying bulk grain will make your batches much cheaper.
What Are You Getting Yourself Into?
There are more benefits to scaling up your homebrew system than just making more beer. True, you get lots more beer for roughly the same amount of work. You’ll find it easier to experiment with the differences between yeast strains and fermentation temperatures and times, and you can try lagering, dry hopping, and using fruits and extracts.
For instance, if you brew 10 gallons of wheat beer, you might put five gallons in a carboy with a chewy, cloudy ale yeast and the other five gallons in a carboy with a spicy Bavarian wheat beer yeast. Or perhaps you’ll add some fresh raspberries to the secondary fermentation of one and not the other. If you take good notes, you will quickly understand the role that subtle differences in process can make. And finally, in the long run you’ll save money. Buying in bulk is always cheaper than buying in small quantities.
Of course, scaling up will cost you, too. You’ll need to invest in at least some new equipment, though you can scavenge most of it cheaply. It will mean more bottle cleaning and filling time. But you should find that the benefits of never running out of homebrew will be worth the extra initial effort.
Big-Batch Equipment
Kettle
The main piece of equipment needed to begin big-batch brewing is a large enough kettle. As your system increases in size, you will have more wort loss in the form of trub and evaporation.
If you are brewing 10-gallon batches, therefore, you will need to boil about 12 gallons of wort. To get 10 gallons of finished beer, you’ll need to use a 15-gallon kettle, two or more smaller kettles, or brew strong and then top off each carboy with a few gallons of sterile water. You could use several small kettles to make up one big batch, but the quality of each individual boil may make each brew taste different and cooling several pots means more work and more mess for you.
If you are brewing with all grain, you have to do a full-wort boil. If you are brewing with extract, you can get away with doing a partial boil (boiling a portion of the wort, then adding water to the fermenter to make up the difference). But it is highly recommended that you begin with a full-wort boil. Full-wort boils will ensure sterilization of the whole wort and increase hop utilization.
The most popular kettle designs for big-batch brewing call for the conversion of a stainless beer keg. European kegs are 50 liters (13.2 gallons), rather than the standard 15.5-gallon American keg. So you can only get about 10 gallons of finished beer out of a 50-liter keg. You can probably squeeze about 12 out of a 15.5 gallon.
Try your local distributor or brewer for old or damaged kegs. Also, kegs sometimes turn up at salvage yards and garage sales, as do, if you are lucky, other potential kettles such as stainless washtubs from old washing machines. Remember, though, that it is illegal to keep and convert a keg if you don’t have permission from the keg owner. The owner is always the brewery named on the keg unless the keg has been previously legally sold.
You can convert a standard beer keg to a kettle yourself by releasing the pressure valve, drilling a hole, and using a Sawzall (reciprocating saw) to cut the top of the kettle out. Stainless is very hard steel, so be careful and wear gloves and goggles when drilling, cutting, and filing. It’s easier just to take the keg to a local welder and have them cut the top for you.
Cut the center out of the top so you retain the maximum volume of the keg and leave the handles intact. While you’re at it, bring a stainless nipple and have them weld the nipple into the side of the keg as close to the bottom as possible for a drain valve. They should do it for about $40 or some free homebrew. There is a company that offers a weld-free conversion kit, too. You cut the top and drill the side hole, and they provide the fittings for a drain pipe and trub screen.
Restaurant supply stores carry large (60 quarts and bigger) stainless stock pots, but they are generally much more expensive than buying a new keg from a supplier. Many homebrew products companies now sell converted kegs complete with drain valves, false bottoms, and even temperature probes.
Wort Chiller
Now that you’re doing a full-wort boil on a big batch, you need a large wort chiller to cool the boiling wort down to pitching temperature as quickly as possible. Wort chillers come in several designs and are simple to construct.
The easiest is the immersion chiller, a coil of copper tubing that is immersed into the boiling wort. Cold water is run from the tap through the chiller, and the wort is cooled to pitching temperature in about 30 to 45 minutes. Immersion chillers have the advantage of being easy to construct, relatively cheap, and easily sterilized by immersion in the wort 15 minutes before the end of the boil.
Fifty feet of 3/8-inch tubing should cool 10 gallons of wort to 70° F in about 30 minutes. Attach a garden hose or plastic tube to the inlet and outlet of your chiller and use the warm water to clean up or water your yard.
The other common form of chiller is the counterflow or “tube in shell” model. In this system, boiling wort flows directly from the kettle into the fermenter, through a copper tube that is surrounded by cold water flowing in the other direction.
To make one you will need about 25 feet of standard garden hose and 26 feet of 3/8-inch copper tubing. You’ll need to buy the outlet fittings for this type of chiller, which are now available in many homebrew shops or through mail order.
The best way to sanitize a counterflow chiller is to let boiling water or sanitizing solution flow by gravity through it before use. The most important thing to remember is to thoroughly flush the chiller with water after each use so deposits do not form inside the coil.
Burner and Gas Source
If you have a gas stove in your kitchen and have been using it to brew beer, you can continue to do so with a larger kettle, particularly if you can place the kettle over two burners. Generally, however, this system is slow and messy.
The easiest solution is to purchase an outdoor-type propane burner. These burners can kick out 100,000 BTUs and more, and will bring 12 gallons of wort to a boil in 15 or 20 minutes. These burners will make your brew day go much faster and often have sturdy metal stands that will raise the kettle to the perfect height for siphoning or draining wort into a fermenter.
You can generally buy a burner with stand, hose, and regulator for $35 to $50 in the homebrew shop. Also, kitchen supply and camping supply stores will often have good, inexpensive outdoor burners. Wherever you purchase the burner, look for the ring burner type as opposed to the single jet models. Single jet burners have a tendency to create hot spots. Make sure that whatever you get is sturdy, because the kettle and wort will be very heavy and not all burner stands are built to carry this weight.
You can pick up a new propane tank for around $20 from camping or large hardware and garden stores. Tanks usually cost about $7 to fill.
If you buy a propane burner, please remember that the gas will give off deadly carbon monoxide fumes and should only be used outdoors or in a well-ventilated area such as your open garage. Brewing outdoors will make the whole process easier and faster, as you can quickly hose down equipment and clean up on the spot.
Mash/Lauter Systems
If you are already mashing, chances are you have what you need, though you may need to enlarge. If you are new to grain, you can buy excellent mash and sparge systems or make them simply from camping coolers. Camping cooler mash tuns use a grid of slotted copper pipe to carry the sweet wort away from the grain, leaving the husks behind. Buying a tall, cylindrical cooler works well, too, with a food-grade plastic disk full of small holes set in a few inches from the bottom. This disk, again, will separate the grain husks from the sweet wort. To make a smooth gravity-feed system, you should add a large (54 quart) cooler that can act as a hot liquor tank, holding the hot sparge water.
A simpler system could use the kettle as a mash tun and hot liquor tank. This system still needs a lauter vessel, which could be double plastic buckets with holes drilled in the bottom of the inside bucket, and a third vessel to collect the wort from the lauter. You’ll have to scoop the mash out of the kettle and then heat the sparge water. It will take more maneuvering and a little longer but should work fine.
Big-Batch Extras
Make sure you have at least two carboys or fermenting buckets, and try to have three. Having three will allow you to do a secondary fermentation, transferring one batch from primary to the third carboy, cleaning the primary, then using it as the secondary fermentation vessel for the second batch.
If you have the space, you may want to aim for long-term ease of use and build a platform to support a gravity-feed system. The top platform supports the hot liquor tank, the middle one the mash tun. The kettle will be on its burner stand a few feet off the ground, and the carboy will sit on the ground. If you do construct a fixed, gravity-feed system, you might want to think about adding a small pump. Inexpensive magnetic-drive centrifugal pumps are easy to find. Pumps will make wort cooling much easier. It’s not easy to lift 12 to 15 gallons of hot water six feet off the ground.
If you have access to additional kegs or large stainless kettles, you might want to think about adding more burners to your setup. Heating the mash and sparge water simultaneously will save you time and makes multiple-brew days go much faster. Burners can be added and easily split to run from the same propane tank.
Process Considerations
Brewing in bigger batches should make your life easier, not harder, so design your system with your own comfort and safety in mind. Remember that you are dealing with more of everything. Twelve or 18 gallons of boiling wort or water is not going to be easy to move, nor is 25 pounds of wet grain. If you ever consider going really big and brewing in one- or two-barrel batches, start thinking about equipment that can be cleaned in place, with more efficient mashing, heating, and cooling systems.
Make sure your lauter system holds more grain, collects as much wort as possible, maintains a deep bed, and leaves enough space for a few inches of sparge water to float on top.
Make sure your hot liquor tank can hold enough water and that it is rated for near 200° F temperatures. Cheap coolers will buckle, crack, and even melt with heat.
Ease the pain of cleaning and filling all those extra bottles. Invest in a kegging system or start using five-liter mini-kegs. Mini-kegs can be naturally conditioned and are a great way to take beer to parties and picnics, and they’ll save about a 12-pack’s worth of bottling. Try dry hopping one and adding fruit extract to another.
Recipe Calculation
It may seem that scaling up your tried and true recipes is a matter of multiplication. In practice there’s a little more to it. Experimentation with your own system is the only way to get a feel for the kinds of recipes you’ll need to formulate.
While big is not necessarily better, since you are up-sizing your equipment you might as well improve the quality as well. A better system means a more efficient one. Making improvements to your milling practice, mash tun design, and mash temperature control can increase your extract yield, making less grain go a longer way. Hop utilization rates will increase with larger-volume boils. Also, a full-wort boil will give better hop utilization.
A larger kettle, more wort, and a better heat source will affect evaporation rate and trub formation. More rapid boiling will produce more hot-break material and more evaporation. Also, a boilover in a larger kettle will lose a much greater volume of wort than a smaller boilover.
Figure out the amount of pounds of ingredients per gallon of finished beer you’ve used in the past, and multiply by the number of finished gallons you expect from your new system. But expect differences. Record, experiment, and adjust accordingly.
