Brew in a Bag or BIAB for short is a very simple, yet highly effective way to brew beer from All Grain. The beauty of BIAB brewing is it only requires a boil kettle, a BIAB bag, and a heat source. This makes Brew in a Bag brewing not only the simplest, but also the most cost effective method of all grain brewing.
In this article I will cover all of the equipment needed, the difference between sparge and no sparge brewing, brew in a bag recipes, as well as insights I have gained over the years of BIAB Brewing. At the end there is a video where I demonstrate the No Sparge method of BIAB. Even if you plan to sparge, the video will still be very helpful.
Benefits of Brew in a Bag Brewing
- Cost effective because you need less equipment
- Faster if you do No Sparge Brewing
- No stuck mashes or sparges, ever!
- Less equipment to clean saving time and work
- Brew beer just as good as conventional all grain brewing systems. (we have the awards to prove it)
Brew Kettle - To decide what size brew kettle you want to use, you will need to decide how big your batch size is going to be. You should also consider what size beers you brew as well. If you brew a lot of high gravity beers you may want to bump your kettle size up. If you brew only smaller gravity beers you may be able to opt for a smaller kettle.
1 gallon batches - 3-5 gallon kettle
2-3 gallon batches - 7.5 - 10 gallon kettle
5 gallon batches - 10-15 gallon kettle
10 gallon batches - 15-20 gallon kettle
If you intend to do no sparge brewing then you will want the larger size kettle listed for your batch size.
If you are doing 5 gallon or larger batches I highly recommend a ball valve for your kettle.
In any kind of all grain brewing, a high quality, calibrated, thermometer is required. If you plan on installing the thermometer in your kettle, make sure to use a thermometer with a short probe, 2 inches or less. If you're not careful, the probe will catch on the biab bag and tear it. I just use a good digital thermometer like this one. Plus it's waterproof and trust me, you will drop it in your mash!
Brew in a Bag Bags
It seems that over the years there is always a lot of arguing in the BIAB community over who's bag is best. I will tell you some things to consider when purchasing a bag.
First, there are a lot of guys that make their own biab bags out of voile. I have no experience with these so I'll have to leave it to you to explore.
My first bag was very inexpensive, and I have to admit that I was able to make great beer with it. It held up ok, I got about 10 batches out of it. The thing I didn't like about it was it was a larger mesh and my wort had a lot of grain bits in it and was very cloudy. I would also find that I would lose about a gallon of beer volume because of all of the trub settling out of my wort.
Since that first bag I have been using purpose built bags from Wilser Brewing and The Brew Bag. These bags are built incredibly well and are designed to perform for many, many, batches. They also have a much finer mesh which will leave your wort much cleaner as well as minimize trub. These bags are also designed to be used with a hoist which makes lifting a heavy bag of wet grain out of the kettle much easier and safer.
I will also tell you that the finer mesh bags are vastly more easy to clean than the larger mesh. With the larger mesh the grain just gets trapped in the mesh and it is a total pain in the ass to clean. The finer mesh bags clean up with just a short spray from a hose or faucet. I like easy!
I highly recommend using a hoist to remove your bag. It just makes it easier and you are less likely to splatter wort all over the place. This is the one that I use. I like it because it has a ratchet to hold it at whatever height you want. If you are doing 10 gallon or bigger batches you may need a pulley or winch system to be able to hoist your bag.
Your heat source can be your stove, electric elements, or propane burner. They all will work. Just choose which heat source works best for you. You do not want to rest your BIAB bag directly against the heat source as it can and will melt. Here is what I do. First I heat my water up to strike temperature, turn the burner off, and then put my bag into the kettle and I pull my bag over the top of the kettle. I secure it to the kettle with bungees or clamps. That way the only heat I apply to the bag is going to be very low heat required to maintain temperature. I have never had an issue with the bag burning or melting. The bag of course is removed before you crank up the burner to bring it to a boil. If you are using electric heating elements be sure to have some sort of false bottom to cover the element to prevent the bag from touching the element.
You will definitely need a good spoon or mash paddle for stirring. Some nice to have but not necessary would be Hot Gloves, pump for re-circulation, hoist, and that's about it for equipment.
With Brew in a Bag you definitely want to crush your grain finer than you would with a conventional all grain system. In BIAB brewing we are not concerned about getting a stuck mash or sparge so the finer crush will help us improve efficiency, especially if we are doing no sparge brewing.
I set my mill to the gap of the thickness of a credit card. I have found that gap to give a really nice fine crush without a ton of flour. Some mills have difficulty crushing this fine so you may have to crush first with a wider gap and then go to the credit card gap and crush it again. The credit card should slide through the gap with a little bit of resistance. It should not be hard to push and pull the credit card through the gap.
I hear a lot of guys say they run it through the mill twice. That helps but you really want to crush it fine the way I described above. At Brew & Grow Minnesota's Grain Room we have two mills. One is for lautering efficiency for 3 vessel all grain brewers and the other is for fine crushing. If you order online you can elect to have a fine crush for Brew in a Bag brewers.
How to Maintain Mash Temperature
This is another area of BIAB Brewing where there are a lot of ways to do this.
If I lose a degree of mash temp I will fire up the burner on low and stir until I gain the degree back which is usually about a minute. I may have to do this 3 or 4 times over the course of the mash.
Some people just turn their burner off and wrap the kettle up in sleeping bags and leave it for the entire mash. I have also seen some DIY insulation wraps made for kettles and they claim they work well.
On the more sophisticated side I have seen systems where electric heating elements are used in conjunction with a PID Temperature Controller that will keep the mash at the set mash temperature the entire mash.
What ever way you choose, the goal is to keep as close to your mash temperature as possible without a lot of fluctuation.
BIAB Sparge vs. No Sparge Brewing
Sparging is the process of rinsing the sugars out of the grain after the mash is done. It helps with mash effiiciency (by rinsing more sugar out of the grain). Basically brewers for ages have sparged their grains and so it was always thought that a sparge had to be done.
If you don't sparge then you have to use more mash water so your mash is going to be much thinner. It was thought that thin mashes created all kinds of problems, and that is another reason we sparge. Bottom line, thin mashes do not create problems. And guess what, you can still get decent efficiency using a thin mash instead of doing a mash and a sparge. Hence, the no sparge process has gained in popularity because it makes great beer and it saves time and work.
The process in the video below is the No Sparge Brew in a Bag process. I have done it on well over a hundred batches and I absolutely love it's simplicity. You simply put all of the water required for your brew into the kettle, heat it up to strike temp, mash your grains, pull the bag, squeeze the bag, and boil!
If your kettle is not big enough to do no sparge brewing, then you will have to do a sparge to get the correct amount of wort. This is where a hoist can come in handy. You can hoist the bag out of the wort and then pour 170° water over the grain until you have your pre-boil volume of wort.
Another way to sparge is called dunk sparging. Essentially put your 170° sparge water in a brew bucket, 7.9 gallon works best for this. Then pull your bag, squeeze it, and then set the bag of grain into the bucket of sparge water and dunk it like a tea bag. Do this until you feel like you have thoroughly rinsed your grain. It will take a lot of dunking, but it's effective!
If you are new to BIAB Brewing I highly suggest using one of our All Grain Beer Recipe Kits. Every one of our 5 gallon all grain kits gives you instructions for no sparge brew in a bag, along with conventional instructions which you can use if you want to do a sparge with your brew in a bag. Our BIAB recipes are developed by our expert brewers and they even include water chemistry instructions.
Developing your own BIAB Recipes
If you are into designing your own Brew in a Bag recipes, it's really not much different than regular all grain recipes. I think there are some recipe calculators out there that are specific to BIAB. I use BeerSmith just because it's the best recipe software out there. All you have to do is set up an equipment profile based on the kettle you are using. I'd recommend setting your mash efficiency at 75% for brews up to 1.060 and 70% for bigger beers above 1.060. That should give you a good starting point until you determine your system's efficiency. Choose a mash profile that suits how you plan to brew. If you are doing a mash and sparge, choose a mash profile that has a mash and sparge. If you are doing no sparge then choose a mash profile that has no sparge. If you can't find a no sparge profile just adjust a mash/sparge profile and eliminate the sparge and the software will do your water volumes for you. It takes some time to dial it in, but good software like BeerSmith is a must.
At Brew & Grow Minnesota we are the Brew in a Bag experts. We have all the biab equipment from electric to gas and we have the best BIAB Recipe kits on the market. We have 3 different BIAB Bags to choose from and the experts to answer all of your questions.
If you have any questions feel free to call the store at 763-780-8191 or you can email me directly at firstname.lastname@example.org.