I just did my first two BIABs with my bag/pulley setup from wilserbrewer. I planned it out using beersmith for a no sparge full boil batch where I would end up with 5.5 gallons in the fermenter. I have a typical 3 vessel setup that I have been using for 10 gallon all grain batch or fly sparge brewing for the last several years. I must admit - its been a while since I did a 5 gallon batch so that was the biggest variable besides the BIAB no sparge process.
I did two separate 5 gallon batches so I could measure and get some reliable numbers on the process using my equipment. The first batch was a pilsner - since I was a bit wary of efficiency estimates, I went big so I would either end up with something huge (1.070) or if efficiency was a problem I would end up with a more typical 1.045 pilsner. Mash efficiency came in at 65% - not bad considering no sparge - I can live with it if I can count on it each time I brew. I ended up with 7.75 gallons pre-boil in my 15 gallon kettle. The first problem I ran into was boil off rate - it was much higher doing a 5 gallon batch than I was used to when I brew a 10 gallon batch.
I use a counterflow chiller that takes the boiling wort to about 85 in one pass. I recirculate in the kettle until the whole thing is down to about 75. With 5 gallon batches, I'm whirlpooling manually using a spoon during and after the chilling process. The wort looked a bit cloudy but not too bad on top when I drained into the fermenter.
I ran into 2 problems (I'm calling them problems but maybe its to be expected).
The first problem is that I ended up with about 4 gallons of wort in the kettle after leaving my typical 1 - 2 quarts in the kettle. The low amount into the fermenter was due to a bigger than expected boil off. I need to lower the boil so as not to boil off so much and/or increase my water/grain ratio to make up for this larger than expected boil off rate. I fear making what was already a super thin mash (by typical all grain standards) even more thin will effect the beer in some bad way.
The second and biggest problem- after putting 4 gallons of wort in the fermenter, I decided to water it down since it was a super imperial pilsner (1.079) and added 1.5 gallons of bottled water. I put it in my chest freezer to chill down from 75ish to 50 so I could pitch my yeast (dry boh pils yeast). The next morning I took it out and could see that about there was about 1.5 gallons of trub/break/schmutz. If I count up all the numbers - out of 4 gallons of wort, I lose 1.5 gallons to trub. This makes for really bad brewhouse efficiency.
I am anxious to hear if there is something I can do to reduce the amount of trub/break that ends up in the kettle. I never really had this issue when doing typical all-grain batches.
l am concerned that making my mash super, super thin to make up for the boil off rate and trub loss will be bad. This batch used a 16.5 pounds of grains and 8.5 gallons of water. If I were to make up for the trub and boil off rates by adding water, I would have had to use 11.5 gallons of water for 16.5 pounds of grain - this makes for a 2.78 quarts/lb of grain ratio - seems kind of scary high to me.
The second batch (a dunkel) was a bit better as I had a smaller grain bill knowing that my mash efficiency was 65%. I had a bit less trub but still about 1.5 gallons less wort in the fermenter - this time I let it chill/settle overnight and use a siphon to get the clear wort off the top and put it in the fermenter. I ended up with 4 gallons of pretty clear 1.059 wort - I decided not to dilute this as it was about what I expected gravity wise.
Overall - I LOVE the time and hassle savings with single vessel, no sparge BIAB. If I can figure out the trub issue, I'll be selling my single tier brewery pretty soon!
I did two separate 5 gallon batches so I could measure and get some reliable numbers on the process using my equipment. The first batch was a pilsner - since I was a bit wary of efficiency estimates, I went big so I would either end up with something huge (1.070) or if efficiency was a problem I would end up with a more typical 1.045 pilsner. Mash efficiency came in at 65% - not bad considering no sparge - I can live with it if I can count on it each time I brew. I ended up with 7.75 gallons pre-boil in my 15 gallon kettle. The first problem I ran into was boil off rate - it was much higher doing a 5 gallon batch than I was used to when I brew a 10 gallon batch.
I use a counterflow chiller that takes the boiling wort to about 85 in one pass. I recirculate in the kettle until the whole thing is down to about 75. With 5 gallon batches, I'm whirlpooling manually using a spoon during and after the chilling process. The wort looked a bit cloudy but not too bad on top when I drained into the fermenter.
I ran into 2 problems (I'm calling them problems but maybe its to be expected).
The first problem is that I ended up with about 4 gallons of wort in the kettle after leaving my typical 1 - 2 quarts in the kettle. The low amount into the fermenter was due to a bigger than expected boil off. I need to lower the boil so as not to boil off so much and/or increase my water/grain ratio to make up for this larger than expected boil off rate. I fear making what was already a super thin mash (by typical all grain standards) even more thin will effect the beer in some bad way.
The second and biggest problem- after putting 4 gallons of wort in the fermenter, I decided to water it down since it was a super imperial pilsner (1.079) and added 1.5 gallons of bottled water. I put it in my chest freezer to chill down from 75ish to 50 so I could pitch my yeast (dry boh pils yeast). The next morning I took it out and could see that about there was about 1.5 gallons of trub/break/schmutz. If I count up all the numbers - out of 4 gallons of wort, I lose 1.5 gallons to trub. This makes for really bad brewhouse efficiency.
I am anxious to hear if there is something I can do to reduce the amount of trub/break that ends up in the kettle. I never really had this issue when doing typical all-grain batches.
l am concerned that making my mash super, super thin to make up for the boil off rate and trub loss will be bad. This batch used a 16.5 pounds of grains and 8.5 gallons of water. If I were to make up for the trub and boil off rates by adding water, I would have had to use 11.5 gallons of water for 16.5 pounds of grain - this makes for a 2.78 quarts/lb of grain ratio - seems kind of scary high to me.
The second batch (a dunkel) was a bit better as I had a smaller grain bill knowing that my mash efficiency was 65%. I had a bit less trub but still about 1.5 gallons less wort in the fermenter - this time I let it chill/settle overnight and use a siphon to get the clear wort off the top and put it in the fermenter. I ended up with 4 gallons of pretty clear 1.059 wort - I decided not to dilute this as it was about what I expected gravity wise.
Overall - I LOVE the time and hassle savings with single vessel, no sparge BIAB. If I can figure out the trub issue, I'll be selling my single tier brewery pretty soon!
