2nd BrewDay - dialing in and a few questions

[landoa]

On today's menu was an American Pale Ale (American Pale Ale II Recipe - BeerCraftr's 1-Gallon Beer Recipes)

Struggled with low OG on the first brew, so made these adjustments:

1. milled grain a second time at home with cheese grater (better than nothing); it took a while so I didnt do a 3rd time
2. added 4oz pale malt to the recipe
3. split strike water into two (mashed in 7l; batch sparged in 2l)
4. squeezed the heck outta the BIAB

Observations:

1. pre-boil OG same as last time (American IPA Recipe - BeerCraftr's 1 Gallon Beer Recipes) --> 1.020 @ 141F = around 1.035 (?)
2. post-boil OG: 1.044 @ 75F
3. pre-boil volume: 8 litres
4. post-boil volume: 5.7 litres, I think

Questions:

1. i've got a 5 litre carboy and the recipe is for post-boil volume of 1.3 gallons = 4.9 litres. should i have a more intense boil next time since i have an extra .8 litres? and this would bump up the OG a bit too.
2. I filled the carboy up to a little under 4l. so is it normal for a recipe to have extra for hydrometer readings and losses? i put the remainder in a separate carboy to test a different yeast
3. there's quite a bit of trub in the main carboy. when measuring volume, this is of course included. so, i guess i will end up with about 3 litres of beer. Is that expected for a 5litre carboy?
4. recipe called to add last hops at the end of the boil. does this mean that i should stop the boil and throw in the hops? or does the hops need at least a few minutes boil time? how do you interpret this?

Thanks for any comments/suggestions!

 

[palmtrees]

One way you could try and simplify things for now is to not sparge. Some people do it with BIAB, and I've tried it, but it just seemed to make things messier and more complicated with little benefit to my process. Just a thought!

On your enumerated questions, here are my suggestions:

1. So it looks like you had 5.7 litres at the end, when you should have had 4.9. That's not a ton extra, really. But if you're concerned about it, then a high post-boil volume means you are either mashing/sparging with too much water, or your boil is not vigorous enough. Looks to me like your issue is with the boil. Your mash/sparge water seems like a reasonable amount, but you're getting less than the 1 gallon/hour boil off that most folks get. With your next batch, try doing a more vigorous boil for the whole 60 minutes and see what happens.
2. The recipe is shooting for 1.3 gallons going into the fermenter because you're generally going to lose about a quarter gallon or so (depending on your setup) to trub and yeast sediment. Plus hydrometer readings, if you don't throw those back in. The 5 gallon recipes don't always account for this loss, but a lot of the smaller recipes do because a quarter gallon matters a lot more when you've only made 1 gallon of beer! You should plan for the post-boil volume listed in the recipe, which probably means you'll need a larger fermenter. You will have a ton of issues trying to ferment 4.9 liters in a 5 liter carboy, even with a blowoff tube. I would suggest using a 3 gallon carboy instead, if you can.
3. That seems like a little more trub than I would expect, but every recipe is different. That could compact down as the beer sits, also. And you can try to cold crash the fermenter to get it to compact a bit more, if you want, thought that risks oxygen exposure as air gets sucked back into your carboy.
4. I agree that "at the end of the boil" is confusingly worded. It would more commonly be labeled as a flameout or 0 minute addition. You can toss the hops in as you turn off the burner. There's no need for them to be boiled when you're doing a flameout addition. They'll get plenty warm as you cool the beer.

Your OG is not super far off and is almost certainly due entirely to the post-boil volume issue. I used this calculator to determine that if you had done a more vigorous boil and gotten a post-boil volume of 4.9 litres, your OG would have been 1.051. So pretty much spot on! I'd say your mash process is pretty good. Next batch, just work on your volumes.

One other note, did you do a mash out like the recipe calls for? It's pretty unnecessary for BIAB, in my opinion. If you want to cut that out next time, feel free to do so. A mash out is generally used by brewers who mash in a tun, and it uses hot water to stop the reactions going on in the grain while the lautering and sparging process takes place, which can take an hour. With BIAB, because your lautering takes about a minute as you pull the bag and drain it, there's no need to stop the chemical reactions. Also mashing out with BIAB runs the risk of melting your bag, if it's sitting on the bottom of the kettle.

 

[cactusgarrett]

Your OG is probably closer than you think - you're note suggests you took the reading at 75F, and assuming your hydrometer is calibrated at 60F, that's 1.044 -> 1.046. Then correct further for the difference in volume as palmtrees suggested.

 

[landoa]

One way you could try and simplify things for now is to not sparge. Some people do it with BIAB, and I've tried it, but it just seemed to make things messier and more complicated with little benefit to my process. Just a thought!

On your enumerated questions, here are my suggestions:

1. So it looks like you had 5.7 litres at the end, when you should have had 4.9. That's not a ton extra, really. But if you're concerned about it, then a high post-boil volume means you are either mashing/sparging with too much water, or your boil is not vigorous enough. Looks to me like your issue is with the boil. Your mash/sparge water seems like a reasonable amount, but you're getting less than the 1 gallon/hour that most folks get. With your next batch, try doing a more vigorous boil for the whole 60 minutes and see what happens.
2. The recipe is shooting for 1.3 gallons going into the fermenter because you're generally going to lose about a quarter gallon or so (depending on your setup) to trub and yeast sediment. Plus hydrometer readings, if you don't throw those back in. The 5 gallon recipes don't always account for this loss, but a lot of the smaller recipes do because a quarter gallon matters a lot more when you've only made 1 gallon of beer! You should plan for the post-boil volume listed in the recipe, which probably means you'll need a larger fermenter. You will have a ton of issues trying to ferment 4.9 liters in a 5 liter carboy, even with a blowoff tube. I would suggest using a 3 gallon carboy instead, if you can.
3. That seems like a little more trub than I would expect, but every recipe is different. That could compact down as the beer sits, also. And you can try to cold crash the fermenter to get it to compact a bit more, if you want, thought that risks oxygen exposure as air gets sucked back into your carboy.
4. I agree that "at the end of the boil" is confusingly worded. It would more commonly be labeled as a flameout or 0 minute addition. You can toss the hops in as you turn off the burner. There's no need for them to be boiled when you're doing a flameout addition. They'll get plenty warm as you cool the beer.

Your OG is not super far off and is almost certainly due entirely to the post-boil volume issue. I used this calculator to determine that if you had done a more vigorous boil and gotten a post-boil volume of 4.9 litres, your OG would have been 1.051. So pretty much spot on! I'd say your mash process is pretty good. Next batch, just work on your volumes.

One other note, did you do a mash out like the recipe calls for? It's pretty unnecessary for BIAB, in my opinion. If you want to cut that out next time, feel free to do so. A mash out is generally used by brewers who mash in a tun, and it uses hot water to stop the reactions going on in the grain while the lautering and sparging process takes place, which can take an hour. With BIAB, because your lautering takes about a minute as you pull the bag and drain it, there's no need to stop the chemical reactions. Also mashing out with BIAB runs the risk of melting your bag, if it's sitting on the bottom of the kettle.

thanks very much for this helpful advice!

1. i agree, i think i need to make an adjustment with the boil. it will be more vigorous next time
2. yeah, i didn't dream of filling the 5l carboy to the top since i'd like the ceiling to remain white. so, i adjusted and filled only 80% to leave headspace. i live in switzerland, so finding carboys is not so easy because nobody cares about beer here, much less brewing it. i just have a 30l bottling bucket and 2 x 5l carboys for the moment and appreciate your 3 gallon carboy advice.
3. i did use a filter, but we'll see what the trub looks like tomorrow.
4. yeah, flameout is easily understood. now i know! i threw the hops in at 2 minutes i think, so it got cooked a bit.

awesome calculator, i wish i had it this morning!

i did not do the mash thinking it wasn't necessary.

thanks again!!

 

[landoa]

By the way, coming back to the mash temps, I think that I fell below the target of 156F because I didnt do a full volume BIAB mash (I mashed in 7 litres and sparged in 2litres, though the recipe called for mash in 9 litres)...so next time, should i bump up the initial strike water temp, say 5 degrees?

strike water initially at 163F
8h35 mashin at 152F ... so i turned the heat back on until it hit 156F
8h50 157F
9h10 155F
9h35 got tired of measuring i think ...