Missed my numbers big time (Zombie Dust clone)

[MC_McMic]

So, I just made my third attempt at all-grain brewing. My first two attempts were 5-gallon batches that were prepared recipes from AHBS. I did them a day apart and nailed my numbers across the board on both beers. It's important to note that this was around 8 months ago, and I basically forgot everything I learned.

Yesterday I made the Zombie Dust clone recipe from right here on HomeBrewTalk (6-gallon batch):

https://www.homebrewtalk.com/f12/3-floyds-zombie-dust-attempt-help-info-requested-245456/

This did not go as well. I don't think the beer is ruined at all, and I don't plan on dumping it by any means, but I thought maybe someone could provide some insight into how I got a bit lost.

Some things to note:

1. I was using a new pot. The difference in width was only 0.4", however.
2. I have never done a 6-gallon batch before
3. I used my previous two attempts at all-grain to calculate my anticipated yield from mash and sparge

Problems I encountered:

1. The yield from my mash was off by 0.5 gal (under)
2. I corrected for this with distilled water after my sparge
3. My boil-off was greater than anticipated with a thinner brew pot
4. My OG was way under what I anticipated: 1.055 vs 1.065

Did I mess up when I added distilled water? Does this account for missing the OG by that much? How does a pot with less width boil off more water? I'm confused.

Also, I did use Bru'n Water, but I'm wondering if I should use BeerSmith for the boil-off and mash/sparge calculations.

 

[shanecb]

The width of the pot is maybe not that important, really. At least in this case since it's not much of a difference. Other things matter such as the thickness of the pot, what it's made out of, etc. It's probably just the case that this particular pot has a higher boil-off rate. At least now you know and can adjust in the future!

Adding in the 0.5gal of distilled water probably made SOME difference, but I'm not sure how much. Maybe 0.004-0.005 gravity points or so?

 

[MC_McMic]

I think I'm gonna do a boil-off test with my new pot with a precise measurement of water. That way, I can at least nail that down for the future. I did a similar test with my previous pot.

Next time, I was also planning on using a larger quantity of water in my mash. I basically want to get the same amount of wort from my mash as I do from my sparge.

 

[smagee]

I could see the half gallon of additional water bringing it down by that much, when compounded by being a few points off due to general mash efficiency, extraction, etc. concerns. It sounds like the brew itself was only off by a few points initially, but came in under volume. This could be due to variations in mash efficiency and absorption, which may have not been factored into your initial assessments as gauged from your previous experiences.

I'd definitely recommend using Beersmith to calculate volumes--especially early on--to ensure that you have a reliable record of what you've changed from batch to batch and dial-in your boiloff rates and general loss.

 

[PatrickLS83]

Welcome to the wonderful world of mash efficiency struggles! Some things to consider here:

1. The lower run-off amount and having to add water definitely made a difference as you probably expected. You might need to dig into your water to grain ratio to sort that out.

2. You could have had a lower efficiency based on the type of grains being used.. I'm not familiar with that kit but sometimes wheat, vienna and rye can get "sticky" and cause a lower efficiency if you're not stirring or recirculating. Rice hulls help with this. In some cases these different grains require a different crush setting which you may have not gotten if you got the grains pre-crushed.

3. The higher boil-off probably helped to concentrate the wort a bit, but not enough to off-set the low efficiency so just imagine what it would have been if you your boil-off was less!

All in all don't feel bad, I've hit worse numbers more times than this and still made great beer. Look at these 3 areas (water to grain ratio, crush setting/grain stickiness, boil-off rate) and try making some adjustments to your process and you should be fine.

 

[TxBigHops]

I also brewed that same recipe on Saturday, and I also came in with a lower than expected OG - 1.056. I noticed as soon as I entered the grain bill into BeerSmith that this was not going to produce 6 gallons of wort at 1.065. I reduced my volume down to a 5.5 gallon batch, and that adjustment hit the numbers in the original recipe. It's possible that the person who wrote the recipe gets higher efficiency with his system than you or I do, so you always need to adjust a recipe for your system.

So you added an extra half gallon of water into the kettle before the boil, right? Is there a reason you didn't just run that extra half gallon through your grain bed? I would suggest measuring the water that you get from your mash, and then using that amount to compute the amount you want for your sparge. For example, if you determine you want to start your boil with 7 gallons, and you get 3 gallons from your mash, you know that you need to sparge with 4 gallons total. Once the grain has been mashed for an hour, it's not going to absorb much/any more water, so whatever amount you put in, you should get back out from your sparge.

But then due to boil off you still ended up with less wort? What was the total volume that you began your boil with, and how much wort did you put into the fermenter?

 

[MC_McMic]

I also brewed that same recipe on Saturday, and I also came in with a lower than expected OG - 1.056. I noticed as soon as I entered the grain bill into BeerSmith that this was not going to produce 6 gallons of wort at 1.065. I reduced my volume down to a 5.5 gallon batch, and that adjustment hit the numbers in the original recipe. It's possible that the person who wrote the recipe gets higher efficiency with his system than you or I do, so you always need to adjust a recipe for your system.

So you added an extra half gallon of water into the kettle before the boil, right? Is there a reason you didn't just run that extra half gallon through your grain bed? I would suggest measuring the water that you get from your mash, and then using that amount to compute the amount you want for your sparge. For example, if you determine you want to start your boil with 7 gallons, and you get 3 gallons from your mash, you know that you need to sparge with 4 gallons total. Once the grain has been mashed for an hour, it's not going to absorb much/any more water, so whatever amount you put in, you should get back out from your sparge.

But then due to boil off you still ended up with less wort? What was the total volume that you began your boil with, and how much wort did you put into the fermenter?

Sorry for the late reply. It's been a crazy week.

I actually did try to run some additional (heated) water through my grain bed, but by that time, it was too late. You have to add quite a bit of water to your grain after you've drained it to get it going again. The 1/2 - 3/4 gallon I poured into my grains just disappeared and never came out (it got suspended in the grains). After that, I was like, "well, I'm not going to heat even more water. I'll just used the distilled I have sitting around."

To address your mash/sparge suggestion, though, I did calculate my mash water loss and sparge accordingly. It just didn't turn out as I suspected. I think this has to do with one or possibly two things:

• I didn't mash with enough water to fully saturate and submerge the grains
• The grains I used absorb more water than the previous recipes I've tried

In the future, I will be more careful to balance my mash and sparge output.

To address your other question, I started my boil with 7.5 gallons. I boiled off close to two gallons with my new pot which was way more than expected. My previous pot was actually wider and boiled off 1.5 gallons per hour pretty consistently.

I'm going to try this recipe again and do several things:

• I'll probably use BeerSmith
• Balance my mash and sparge
• Test my boil-off rate with my new pot

I'm looking forward to trying again and correcting my mistakes. In the meantime, I'm sure my current batch will turn out tasting great. I'm just a perfectionist. So, when things go this far awry, I freak out a little.

I just moved the beer to my secondary, and I'm excited to try it out in a few weeks.