Once you go from homebrewing with kits to extract brewing, the thirst to keep advancing and improving might just grab hold of you. Before you know it, you’ll want to get into all grain brewing. Once you decide to go that way it can be somewhat daunting with all the possible options for your setup. Fortunately, there’s brew in a bag, an easy one vessel transition to all grain brewing.
What is brew in a bag (BiaB)? To understand BiaB you need to understand the all grain process. When all grain brewing, you prepare a mash by steeping the required grains in warm water to encourage the breakdown of starch into simpler sugars that yeast can ferment (saccrification). Once all starch is broken down, the sugary liquid (wort) is drained through a false bottom and transferred to a kettle, leaving the spent grains behind. The wort is then boiled and hops are added just as they would be in extract brewing. BiaB changes that process slightly. The grains are added, in a large fine mesh bag, to the water in the kettle. Once saccrification has occurred the bag is removed taking the grains and leaving the wort in the mash kettle. The wort can be brought to the boil and hops added, just like when extract brewing.
As an additional step to increase extract yield you can put the bag in a strainer over another pot and rinse with a gallon of water at your mash temp. This can be collected and then added to your main pot.
There are a couple of advantages to BiaB when starting out:
Little additional equipment – If you have been extract brewing you will already have a large brew kettle. Make sure you have enough volume in the kettle to accommodate the grains you will use. You may need to downsize your brews if your kettle is smaller. Otherwise you really only need to get an appropriate BiaB bag to put your grain in.
Easy transition – just as you won’t need a lot of additional equipment, it’s not a steep (pardon the pun) learning curve from extract brewing. Use a calculator like Beer Smith to work out what grains you need and add them in a bag instead of dissolving extract. The saccrification step takes a little longer, but it’s not a whole lot more complex. Just remember that the grains need to be milled, otherwise the mashing won’t work. From there the process is the same.
A few tips for BiaB:
Get a big bag – The amount of grain will vary depending on the style your brewing. You don’t want to have filled your bag and still have half of the grain left. Get a bag big enough to fill the kettle with an opening as big as your pot. If it has a draw-string that can tighten around the top of the kettle to ensure that it doesn’t slip in emptying the grains into the water, that’s even better.
Brew low – If you have a burner that is a bit lower to the ground, use it. That bag of grain will have soaked up a lot of water. If it’s a big grain bill, it’s going to be heavy. If you can lift it to chest height rather than head height (if your brewing in the kitchen) there’s less chance of a mishap.
Start simple – This isn’t a rule for all time, but useful when starting out. You’ll have a lot more going on than extract so keep the recipe simple like a SMaSH to start with. This will ease you into the process while you get a feel for it.
Calculate your water – One big difference with all grain brewing compared to brew in a bag is that the grain you are adding will soak up some of your water. To compensate for this, add an additional 0.1 gallons for every pound of grain in your recipe. As with extract brewing you will need to add water to account for evaporation losses during the boil. We tend to use ¾ gallon for every hour of boil. This will be different depending on your kettle size, surface area and how you’re heating it, so you’ll have to take note the first few times you brew. The other water consideration is temperature. When you add grains to the water the temperature will drop. We add 8⁰F, so if your mash target is 152⁰F then you need to heat the water up to around 160⁰F. Once you add your grain it should level out around where you want it. If you find the grain cools it below the target you could add another 4-5⁰F the next time you brew.
That’s all there is to it! It’s a fairly simple transition from extract brewing that will open up a whole new level to your homebrew.
Have you used BiaB? Want to share any stories or recipes? Leave a comment.