Brew-in-a-Bag (BIAB)

As I said in the first post about National Homebrew day, my brewing method is based on the BIAB method described by ‘Thirsty Boy’ on the Brewing Network’s forums. I have put together a few shots of my brewing day, just to compare to Justin’s more normal home-brewing set up. Please note that Justin brews 10 gallons per batch, compared to my 3.3 gallons - it may be difficult to scale the BIAB method much above 5 gallons, or so I hear.

The usual procedure in home brewing is to gently mill your grain - taking care to crush the grain rather than grind it, as the husks should be kept as entire as possible. These are put into a mash tun - usually some sort of picnic cooler with a manifold of one type or another at the bottom to allow drainage of the mash. Water is heated in the brew kettle to a strike temperature considerably above the mash temperature - it will decline when mixed with the milled grain. The mash is allowed to rest for about an hour. The mash mixture is then drained - the first runnings are ‘recirculated’ back into the tun, to ensure clear wort. Additional hot water is poured into the mash tun to ’sparge’ the grain - wash out remaining sugars. This wort is then boiled with hops, and fermented.

In contrast, here is the method I use:

There is my mash tun/brew kettle, lined with a mesh bag I sewed up. The fabric was from Walmart for like $2/meter, and that's about all you need. The pot holds a bit over 20 L.

Here are the results of my hand grinding in a corona-style mill. That's about 2.5 kg of coarsly (relative to flour) milled grain and whole wheat flour. I use up to 1/3 whole wheat flour in my grain bill - it costs about as much as base malt, but is much easier to get.

Here the milled grain has been dumped in the 'mash tun'

Literally 'doughing in': mixing the water in with the grain. As the grain is so finely milled, dough-balls are more of a concern I think, but I have to be carefull not to over-work the porridge, as it could really become dough-like due to the high wheat flour content.

Here the 'mash tun' has been lifted over to a cool burner and is mashing for an hour. To keep things simple, I add the hottest tap water possible (around 55 degrees) to the grain, then directly heat the mash to around 67 or 68 degrees (takes about 10 minutes). The mash will decline in temperature to about 65 degrees over half an hour. I reheat it for a minute or two up to 68 degrees again, and let it sit for another half hour.

Here's my thermometer showing the mash temperature, I think about 10 minutes in.

This is what the mash looks like after mashing for an hour. As opposed to usual mashing, I add all my water at the beginning of the mash, and do not sparge - I simply lift out the grain-bag, thus straining out the work. Sorry, forgot to take pictures of this part. It usually takes about 10 minutes to drain out the bag - I try to squeez out as much wort as possible (no tannin problems, yet).

Another view of the completed mash. From here on, my method is broadly similar to traditional home brewing (boil for an hour adding hops along the way, drain wort off trub, ferment).