Newbie needs help with first All-grain BIAB Partial mash

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dieWerner

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Hi guys

I'm still a newbie, with only 4 brews under the belt, so I have a lot of questions for all the hardcore all-grain brewers!

This past weekend I decided to do my first all-grain batch using BIAB, I bought the largest pot that I could find, a 20L Hart Alu pot, which I prepared by boiling water in it for 30 mins.

I followed all the instructions, tips, tricks, etc that I could use from reading many forums:
- Steeped all the grains ('bout 5kg) in 15L water of 65C for 60 mins
- did a "Mash-out" by raising the temp to 75C and letting it sit for another 15mins, 75mins total. (the extra 15mins was supposed to help with my "efficiency", more on this later)
- lifted and drained the bag, squeezed as much wort out as I could (as I read that squeezing is considered good by some, bad by others, so I chose to do it anyway)
- "Sparged" by pouring 3L of 70C water over the bag in various places, and squeezed again.

- Boiled for 60 mins, added hops/irish moss at the all the right times (something that no-one tells you: don't do this indoors, in winter, with all the doors and windows closed, the steam got everywhere and I've now got sticky walls, cabinets, microwave etc... :smack:)
- Rapidly cooled the closed pot in an ice bath, whirlpooled, and added everything to my fermenter, and topped up to the 23L mark, as per my recipe.

Right, now this is where I need help; the recipe states that after diluting the wort in the fermenter by topping up with clean water up to 23L the OG should be 1.051 (down from supposed post-boil of 1.066, forgot to measure), but I got 1.043? What the hell went wrong? (BTW, reading was taken at 14C, before rehydrated US-05 yeast was pitched)

What can I do to get my efficiency up?

After a bit of googling, I found a calculator that worked out that my efficiency is 63%, but the recipe is formulated for 75%...

Sorry for the ridiculously long post, I'm just trying to make sure that get all the necessary info together.

Thanks in advance for any help!
 
What can I do to get my efficiency up?

VERY fine grind (I get about 30% flour and the rest is tiny) is needed for BIAB...this not how it will come from a homebrew shop unless they will double grind it.

63% is not terrible for a first try with grain that was likely ground for a traditional 3-vessel process. As it is unlikely you will get most online retailers to double crush, consider just calculatng at 63% and buying more grain. It usually is the cheapest ingredient in your beer unless your shipping costs high.
 
That's not bad for your first attempt! Things to work on:

1) holding temperature as precisely as you can. Mashing is a lot more sensitive than steeping speciality grains. Make sure you have a good thermometer.

2) make sure you have a pretty fine crush on the grains. BIAB works best with a fine crush.

3) ideally you will want to be using a full volume boil and mash. I use a 40l pot for a 23l batch.

For your first batches, take hydrometer or refractometer readings at the end of your mash, and be prepared to add a bit of extract to get to your target preboil OG.
 
3) ideally you will want to be using a full volume boil and mash. I use a 40l pot for a 23l batch.

Thanks for the great info guys.

The reason that I'm asking about upping my efficiency is that my pot really doesn't have any more space to add a few extra kg's of grain or water, it's close to the brim of the pot, I'm trying to better utilize that which I have.

I've been reading a few other blogs and forums, and people have a lot of opinions regarding the pH of the mash water having a very high influence on the conversion. What do you think?

After a bit of googlery I've found the water report for my area and the tap water's pH is 8.11, and the mash water supposedly should be between 5.4 and 5.7.

I've entered all my water specs into an online water calculator and my mash pH comes out as 5.9...
 
One thing I would also caution is that if you took your measurement after topping off with water you could have had a mixing error. It's difficult to get water fully mixed with the concentrated wort. On the occasional batch that I top up I measure the OG of the base wort before topping up, then if you know your volumes you can calculate the true OG.

In addition to the advice above about increasing your crush you may also want to experiement with dunk sparging. I also don't have a big enough pot to do full mash but I found I got better efficiency with the dunk rather than pouring over. Except possibly on very dark beers, most folks need to add some acid or acid malt to bring their mash pH down to range and it looks like you do as well.
 
Thanks for the great info guys.

The reason that I'm asking about upping my efficiency is that my pot really doesn't have any more space to add a few extra kg's of grain or water, it's close to the brim of the pot, I'm trying to better utilize that which I have.

I've been reading a few other blogs and forums, and people have a lot of opinions regarding the pH of the mash water having a very high influence on the conversion. What do you think?

After a bit of googlery I've found the water report for my area and the tap water's pH is 8.11, and the mash water supposedly should be between 5.4 and 5.7.

I've entered all my water specs into an online water calculator and my mash pH comes out as 5.9...

It's not the water's pH that's important for mash pH, but rather the water's alkalinity. In any case, at a pH of 5.9 you are quite far outside of the optimal range (5.0 - 5.5) for beta amylase, which is the more active of the amylase enzymes at your mash temperature. The relatively low mash temperature will slow the starch to sugar conversion rate compared to higher temps, and the high pH will slow the rate even more. Combine those effects with a coarse crush, which takes longer to convert due to greater required diffusion distances, and you have three things working against your mash efficiency. So, 60 minutes was too short a mash time for your mash conditions.

Your mash out put you in a temp range that speeds up the amylase reactions but also denatures the enzymes. The beta amylase will denature very fast at 75°C, but the alpha will stick around for a few minutes and work on converting more starch to sugar. You would be better served by extending your mash time to get more conversion, rather than depending on the mash out to help your efficiency.

So, my recommendations:
  1. Crush your grain finer if possible, as others have said.
  2. Extend your mash time for more complete conversion (even more important if you can't crush finer.)
  3. Use a water calculator to adjust your brewing water to get your mash pH into a better range.
Good luck with your next batch. You did OK on your first, so you have a good baseline from which to work on improvements.

Brew on :mug:
 
Mash out... you don't need it with a BIAB modified batch sparge.
If you really want to get into your water, find a test report for your water, or get one by sending a sample to Ward Labs. Then use any of the good water calculators like Brewers Friend.
You may need to get your own mill if you can't get a very fine grind from your LHBS. A $25 Corona mill works fine for BIAB.
Consider either getting bigger pots, or making smaller batches if you want to achieve full boil batches.
 
LIST=1][*]Use a water calculator to adjust your brewing water to get your mash pH into a better range.
[/LIST]

Right, as was suggested, I used the brewersfriend.com online calculator and went for the "Balanced Profile" setting, I found everything in the water report except for the "Bicarbonate" amount, here I just guessed 100mg/L

It calculates my mash pH as 5.9, and in order to bring it down to 5.5 I need to add any one of the following:
  1. 2.3ml of lactic acid
  2. 23.71ml of Phosphoric acid
  3. 6.97ml of CRS/AMS
  4. 2.31ml of Hydrochloric acid
  5. 0.74ml of Sulfuric acid
  6. 38ml of Acetic Acid
  7. 2.88g of Citric acid
  8. 2.07g of Tartaric acid

My LHBS only carries:
  1. Ascorbic acid
  2. Citric acid
  3. Malic Acid
  4. Tartaric Acid

Most forums that I've read yesterday mention Lactic acid, but no amount of googling has shown me where I can buy that...

People also mention that they can taste even small amounts of citric acid, and I know that it is used in baking as well...

Also, I don't see Acid malt anywhere on the LHBS website so that's not an option

That leaves me with tartaric acid, does anyone have any experience using it:confused:???
 
Last edited:
Right, as was suggested, I used the brewersfriend.com online calculator and went for the "Balanced Profile" setting, I found everything in the water report except for the "Bicarbonate" amount, here I just guessed 100mg/L

It calculates my mash pH as 5.9, and in order to bring it down to 5.5 I need to add any one of the following:
  1. 2.3ml of lactic acid
  2. 23.71ml of Phosphoric acid
  3. 6.97ml of CRS/AMS
  4. 2.31ml of Hydrochloric acid
  5. 0.74ml of Sulfuric acid
  6. 38ml of Acetic Acid
  7. 2.88g of Citric acid
  8. 2.07g of Tartaric acid

My LHBS only carries:
  1. Ascorbic acid
  2. Citric acid
  3. Malic Acid
  4. Tartaric Acid

Most forums that I've read yesterday mention Lactic acid, but no amount of googling has shown me where I can buy that...

People also mention that they can taste even small amounts of citric acid, and I know that it is used in baking as well...

Also, I don't see Acid malt anywhere on the LHBS website so that's not an option

That leaves me with tartaric acid, does anyone have any experience using it:confused:???

What's the URL for your LHBS?

Brew on :mug:
 
Greetings back at ya from the other side of the world.

Looks like BrewCraft has a rather limited selection. Do you have any other sources available for brewing supplies?

Brew on :mug:

Not close-by where I live, this is my preferred supplier
 
Right, as was suggested, I used the brewersfriend.com online calculator and went for the "Balanced Profile" setting, I found everything in the water report except for the "Bicarbonate" amount, here I just guessed 100mg/L

That doesn't sound like a good idea. This is one of the crucial things that determines mash pH, the calculator is not going to work if you don't have the values to plug in. Does your water report list "alkalinity"? Alternatives are to get a water report from ward labs (though don't know how shipping would work where you are) or start with RO water. What does the rest of the report look like?
 
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