- The kettle: This kettle is the ONLY vessel required to BIAB. The only special requirement is that the kettle have a volume of at least 15 gallons for a 5 gallon brew session. This is because this one vessel will have to hold your entire water requirement as well as your grain bill. This volume will regularly exceed 10 gallons. You will mash and boil in this vessel.
- The bag: This is a mesh bag that is large enough to conform to the inside diameter of the kettle and reach over the top lip. This bag is sometimes likened to a large pillow case, the kettle should be able to fit INSIDE it while still being able to close the top of the bag. Typically composed of “voil” or another mesh like material, this will hold your grain bill and must be strong enough to hold the water saturated grain when you lift it out of the mash water at the end of the mash.
- The heat source: This can be the typical “turkey fryer” burner that is used widely by home brewers. Also on the market and better for keeping consistent temperatures are electric brewing systems, utilizing heater elements that go right into the kettle. The heat source will be utilized to provide heat for strike water, maintaining mash temperature, mash-out and the boil.
Crush your grain finer than you would with a typical all grain brew. This is because you no longer have to worry about a stuck sparge. The bag is the filter and the finer crush will improve your conversion efficiency.