Dilemma—Attaining Proper Gravity at Maximum Carboy Capacity

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bmboileau

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Hello All!

I am new to Homebrewtalk and to homebrewing, having made only three full 5 gallon batches of beer. I have a question that has been bothering me. Recently, I tried to make a 9.6% russian imperial stout. I use an iphone program to track my grain and adjuncts and so I went to my local supplies store to pick up my grain (huge grain bill). I asked one of the workers where the 19L (5 gallon) line on the carboy was so that I would know where to fill up water to. See, for the past few batches, I have been quite strict about using only 5 gallons of water overall (using a portion for the steep and boil, and then adding the remaining in to the fermenter with the wort with a little extra to account for some boiled off). However, this has only given me batches around 13L and I see everywhere pictures of entirely full carboys for other homebrewers.

So, I steeped the grain for my stout and then boiled with some additional sugars, hops, etc. Cooled and added it to the carboy, topping it up to the proper 19L line (or what I was told), and took a gravity reading—1/3 the gravity I expected. My questions are this: Should I always expect in homebrewing that I will add water to the fermenter incrementally, taking readings as I go until I hit the gravity I want, and then potentially not have full 19L batches? Or, is there something I should have kept in mind about water additions and/or a tried and true method for ensuring you get proper gravity and maximum capacity?

Anything would be helpful! Thanks!
 
When you topped it up the water didn't mix thoroughly with the wort. It's surprisingly hard to do. Try this. Put some water in a drinking glass (glass preferred so you can see through it well) and the add a little dark color honey (or light if that is what you can get). The honey will go right to the bottom. Now take a toothpick and stir the honey in. Did it mix?
 
If you're using extract, and you're properly measuring the water volume once everything's in the carboy, it's really impossible to "miss your OG" unless you forgot an ingredient or left wort behind in the kettle. If your recipes are designed for 19 liter batches, you want 19 liters in the fermenter. Sounds like you didn't add enough topoff water for the previous batches.
 
So, I used a full grain bill (over 16 lbs of marris otter and others) and then added some saskatoon berry syrup during the boil for flavour. I assume I did something wrong at the mash if I had a wrong OG (was supposed to be 1.098+ and turned out to be 1.042). Thought I had done everything right, hmm. Thanks you too, I will see next time I guess.
 
If you're brewing all grain it's a completely different story. I figured it was extract since you were talking about steeping and topping off. Most all grain brewers don't top off, since we want all the water to be used for sparging. Are you set up to do a full boil? If you want a 5 gallon batch, aim for about 6.5 to 7 gallons preboil, depending on your boiloff rate.

It sounds like you need to give us more information about your mashing/lautering/sparge process, your volumes at each step, your typical mash efficiency, preboil volume and gravity, boil length, etc. If you aren't keeping track of these things and making sure they're consistent, it's very difficult to troubleshoot.

If you're trying for a 1.098 beer, and you're only doing a partial boil, your mash efficiency is going to be absolutely miserable. Below 50% I'd say. You want all the extra water you can so that you can sparge with it, any topoff water is basically "wasted".
 
RM-MN: No, just after I put both wort and water into the carboy.

zachattack: Yes, what I meant when I said I was topping off was that I had my water for the mash, and the water I added later was to compensate for water evaporated during the boil and to bring the volume up to 19 l. Mine is a haphazard system and I think I am realizing how much more I need to be prepared for. My mash is done with nylon bags, the grain placed inside, steep at temperatures controlled up and down on the stove (not the most ideal). My sparge is running water through the grain in the bags after I have pulled them out and left them suspended about the pot. Here are my steps for the mash:

Glucan Rest at 112F for 10 min
Protein Rest at 122F 25 min
Medium Body Infusion at 154F for 30 mins
Full Body infusion at 158F for 15 mins
Mash Out at 170F for 10

Unfortunately, and here is a huge omission of my inexperience, this being my first all grain trial I wasn't prepared for how much grain I'd have to use. So, I did the mash twice. My brew kettle is only 19quarts and, so, I had to mash twice (half the grain in one bag and half in the other). I've been reading some stuff since and realize proper water to grain ratios for mashing, I was way off. In terms of volumes, I had roughly 13-14 quarts for the mash, adding 3 quarts (roughly) during the sparge of the first grain bag. Mash Efficiency is a concept that eludes me... Couldn't tell you exactly what my preboil volume and gravity, boil length was 1 hr.

Two things are pretty clear, 1) many more measurements to track and 2) might have to put off AG brewing until I have more suitable equipment.
 
Sounds like you're doing BIAB, which is definitely a solid method, and a lot simpler than traditional all grain brewing. I don't have any direct experience, but I'm sure others can chime in.

For starters, I'd recommend switching to full boils if you can, and eliminating the top off. Keep track of everything using good brewing software if your iphone app isn't cutting it. I recommend checking out a free trial of Beersmith.

Mash efficiency is just what % of the sugar you extract from the total available in the grain. Your brewing software should help with that as well.

http://www.howtobrew.com/section2/chapter12-5.html

I'll also recommend you start out with a single infusion mash for simplicity. Step mashes are almost entirely unnecessary with modern malts.
 
Thanks for all of this, I really appreciate the help! Just a final few concerns, does the 1.25 quarts / 1lbs of grain stand as a good mash volume? Does a full boil mean that you mash and boil with a certain volume and never top up that water? If yes, how do you adjust for water lost when removing the bags / during the boil? Do you just add more water than you need?
 
1.25 qt/lb is fine for traditional all grain, to be honest I'm not sure about BIAB! And now that I think about it, I'm not sure if switching to a full boil is as beneficial, since a lot of BIAB-ers don't sparge at all. So I think someone else could definitely help out more than me there!

But yes, you just start with more water than you need. Like I said above, most people start with a 6.5-7 gallon preboil volume. That's not including the amount that's absorbed by the grain.
 
Thanks for all of this, I really appreciate the help! Just a final few concerns, does the 1.25 quarts / 1lbs of grain stand as a good mash volume? Does a full boil mean that you mash and boil with a certain volume and never top up that water? If yes, how do you adjust for water lost when removing the bags / during the boil? Do you just add more water than you need?

A full boil means that everything that goes into the fermenter came from the kettle.

To make a 6-gallon batch of beer, I start my boils at 7.5 gallons. During the 75 minutes (my normal boil time), I lose probably 1.25 gallons, and leave another .25 gallons in the bottom of the kettle / absorbed by the hops. It's not starting with more water than I need... it's starting with exactly the right amount of water! :D



Now, the big problem with doing a partial boil then topping off the fermenter for all grain is that you don't have enough water to get the sugars out of the grains. There is a certain maximum level of sugar you can get water to absorb. Most people "sparge" their grains by running additional water (in addition to the 1.25 qt./lb) through the grains and into the kettle, pulling out more sugar with fresh water.

Sounds like you got poor efficiency because you didn't have enough water to pull that much sugar out.
 
I do BIAB all grain in a 20 qt (19 L) pot but to get the BIAB system to work for me I do half size batches. I start with about 15 L of water, bring that to strike temperature. This will be closer to 2.5 qt/lb. Stir in the grains and let them sit at mash temperature. Pull the bag out and squeeze out all the wort you can. Then start raising the temperature for the boil. I estimate how much water will boil off (about 3.5 L for me) and check the level of the water in the pot. If it is too low I can pour a little more through the bag of grains to extract a little more of the sugars and add that to the pot. When the boil is nearly over if I have too little wort, I can add a little water to the boil. If I have too much, I can boil a little longer to get my amount I want to go into the fermenter. By adding the water during the boil it will mix properly instead of stratifying.

The key here is to start with all or nearly all the water that you want in the fermenter plus the amount you estimate you will boil off. If I want to do a 5 gallon (19L) batch, I need a bigger pot. For brews in the 1.050 to 1.065 OG, I can make it work in a 7 1/2 gallon pot (30 quarts, about 28L?) but I have to watch for boil overs.
 
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