This blog subject came about as I was strolling the sidewalk on my way to day two of the American Homebrewers Conference. I was walking with my conference buddy Brian, and we ran into a well known voice from The Brewing Network. A fellow known for his "taste" buds and brewing stature.
He had heard of the brew in a bag method, but had never ventured into the magical world on his own. As we walked I asked what his opinion of the method was. His first comment was "well, I've heard it's not as efficient and doesn't take as long".
In our quest to make the brew in a bag method the viable alternative to 3V brewing, a response of that sort is music to my ears. It means that the guys who influence the brewing community are not fully aware of the method's potential to change how most brewing is done in the USA; and we have great potential to change it through them.
I've done a bit of math regarding the filtering capacity of a typical brew bag vs a manifold pickup. When I first started to put my mash tun together, I decided that the braided SS cord that wraps a water line was the cheapest most efficient way to get my wort out of the grain bed and into the boil kettle. It was 14" long and was about 3/4" diameter. When I first put it together I imagined how clear my wort was going to be after being filtered through that fine mesh. Time was of no consideration as this was "the only way" to make that happen, and a brew day was supposed to be relaxing and filled with satisfaction.
I never used that tun or the filter line because I got frustrated with the ball valve not fitting correctly and threw the whole mess in the tun for another day.
If I had taken that filter line and split it open, laid it flat and measured it, the total square inches of filtering surface would have been about twenty-one. I've seen most guys use either a braided cord, drilled pvc, or copper pipe as their wort filter. They are very careful when making their manifold as the holes have to be just right in order to let the wort through, but small enough to keep the grain particulates out. They always hold their breath on the first use, and for that matter, every time beyond that as they begin to drain the wort into the boil kettle. They hold their breath so the stuck sparge can be fully recognized with a vigorous shout!
Depending on the size of the kettle, The Brew Bag's filtering surface is about 1044" square inches - that does not include the part of the bag that is above the water line. A very experienced brewer I know just pulled his SS cord out of his cooler mash tun and used The Brew Bag for Coolers for the first time. He said in a FB post that the wort into the boil kettle was the clearest he'd ever seen. It took four minutes to drain 3.6 gallons into his boil kettle instead of the usual fifteen. His efficiency using his old cord set up prior to using the bag was consistently 80% - this batch was also 80%. Make sure somebody over at The Brewing Network reads this post - same efficiency as 3V sparging but less time and effort.
Here's a photo of his cooler with The Brew Bag for Cooler's ready for the addition of strike water and grain.
Here's photo of the wort that would have been left as dead space loss using his braided cord and typical mashing technique. He left the pick-up tube and ball valve from the old set up in place.
Here's his old filtering set up.
The Brew Bag inserted in the cooler with strike water added.
This is the bag just after dumping the grain and prior to rinsing. The Brew Bag is cleaned with water and hung to dry.