Recipe Totals Not Matching Expected OG/FG/ABV

obesechess

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Hi there!

I am working off an old family recipe written down on an old Brewer's Friend Brew Day sheet. This will be my first time brewing and am trying to streamline my process by loading stuff onto a computer. I am putting the ingredients into the recipe editor, with very slight variations in brand, etc - for example, Brewers Friend does not appear to have Munton's chocolate malt loaded in, so I'm just loading the closest chocolate malt I can find. I've only had to make maybe two such substitutions in a seven-ingredient grain bill weighing in at about 13lbs, and only in two ingredients weighing a total of one pound combined. Hops I'm in a similar boat, matching AA% and hop type rather than specific brands.

Despite this, the Original Gravity calculation being made by the recipe builder is low by about .009 and the Final Gravity calculation is high by about .004. I presume these are within the margins of error - IBU is similarly off by just a little bit - but what's getting me is the ABV - the estimated ABV on the recipe I have is 6.4%, the ABV according to the recipe builder is 4.8%.

If I use the "goal" setting and adjust percentages, I can get closer, but it turns the 13lb grain bill into a 15.29lb bill and I have to add things like "8.39lbs of 2-row," and even then it only gets me to 5.6% ABV.

I don't know enough about brewing, hilariously enough, to begin to troubleshoot why these numbers are so off. Any thoughts as to where I should start? Tweaking the mash guidelines seems to slightly adjust these totals, but only slightly, and I'm not sure I'm putting the mash guidelines in correctly.

Any help is appreciated!

Thanks!
 
Hi there!

I am working off an old family recipe written down on an old Brewer's Friend Brew Day sheet. This will be my first time brewing and am trying to streamline my process by loading stuff onto a computer. I am putting the ingredients into the recipe editor, with very slight variations in brand, etc - for example, Brewers Friend does not appear to have Munton's chocolate malt loaded in, so I'm just loading the closest chocolate malt I can find. I've only had to make maybe two such substitutions in a seven-ingredient grain bill weighing in at about 13lbs, and only in two ingredients weighing a total of one pound combined. Hops I'm in a similar boat, matching AA% and hop type rather than specific brands.

Despite this, the Original Gravity calculation being made by the recipe builder is low by about .009 and the Final Gravity calculation is high by about .004. I presume these are within the margins of error - IBU is similarly off by just a little bit - but what's getting me is the ABV - the estimated ABV on the recipe I have is 6.4%, the ABV according to the recipe builder is 4.8%.

If I use the "goal" setting and adjust percentages, I can get closer, but it turns the 13lb grain bill into a 15.29lb bill and I have to add things like "8.39lbs of 2-row," and even then it only gets me to 5.6% ABV.

I don't know enough about brewing, hilariously enough, to begin to troubleshoot why these numbers are so off. Any thoughts as to where I should start? Tweaking the mash guidelines seems to slightly adjust these totals, but only slightly, and I'm not sure I'm putting the mash guidelines in correctly.

Any help is appreciated!

Thanks!
It might be your efficiency setting mate. Try raising your efficiency higher and that will increase you PPG / extraction of sugars yielding a higher OG for the amount of malt you use. But remember this number is changed usually after a brew day or three.

If you've brewed that recipie before and got great results and met your brew day targets SG Volume Final Gravity Ect ect then don't change it because the recipie editor doesn't reflect it.

Why don't you brew the recipie but record in detail your mash temp mash volume before after your losses and final volume you actual OG and Final Gravity. And start using this as a benchmark to tweak your brewing profile to hopefully in a couple of brew sessions getnthe calculator to line up with what your seeing in the brewery.
 
Setting up an equipment profile that accurately represents your brewery and a reasonable expectation for efficiency goes a long way towards getting accurate predictions from any brewing software. Simply entering ingredients doesn't give the program the information needed to make reasonable predictions. Your inputs are required for that.
 
Great, thanks. I haven't really figured out the equipment profiles, but it makes sense that that, plus efficiency, would be the key. I assume from Trialben's comment that what's more important is just making the recipe the way it's written rather than worrying about expected abv values, etc.
 
I agree with trialben on brewing the recipe as written. If you knew your efficiency and had an accurate equipment profile you could make adjustments as needed to meet the specifications of the recipe, but for now, just brew it as is.
 
Cool. Yeah, the recipe has about 19 batches worth of notes so I'm going to trust that it's largely accurate. I can always ask the recipe author for help, too. Just wanted to make sure I wasn't totally messing something up. Thanks!
 
Cool. Yeah, the recipe has about 19 batches worth of notes so I'm going to trust that it's largely accurate. I can always ask the recipe author for help, too. Just wanted to make sure I wasn't totally messing something up. Thanks!
Always go with reality over prediction: If it's raining outside and the forecast was for sun, would you leave your umbrella at home? Same with brewing.
 
Ha! Yeah. There's a few more things that don't look quite right, but I'll ask the folks at my LHBS when I pick up the grains since they'll know my equipment better, and defer to the recipe as written as I remember the beer being quite tasty as written. :)
 
Ha! Yeah. There's a few more things that don't look quite right, but I'll ask the folks at my LHBS when I pick up the grains since they'll know my equipment better, and defer to the recipe as written as I remember the beer being quite tasty as written. :)
I've generally gotten good results with the Recipe Builder, nuisance "improvements" aside. I mostly ignore the FG predictions, mine usually comes out lower, leading to a higher than predicted ABV. The OG predictions, accounting for variability in ingredients and boil-off, are generally acceptable although I keep some boiled, cooled water and DME on hand for adjustments, sometimes necessary. I have no way of knowing if the IBU calcs are right - I'm at 6,000 feet so due to lower boiling temperature, have to adjust hops up to get a decent bitterness. So all in all, the variability of the ingredients and conditions notwithstanding, the calculators do a pretty good job of prediction. But always favor the reality of your brewing conditions over the predictions of any software. There are too many variables to predict everything accurately.
 
Yeah, and hey, the worst that happens is I brew it, it doesn't come out just right, and I'm out like $30 in ingredients and have knowledge of how to improve next time.
 
Okay. Just for laughs, one more. There's absolutely no way my mash pH is 4.1, right?
 
it is not my recipe to share and have been asked not to share it publicly by the family member who gave it to me, or I would, but I'll give you what I can - in playing around with the recipe, it appears that removing the Briess Chocolate Malt, one pound in a 13lb grain bill, brings the mash pH up from 4.1 to 5.6. It seems unlikely that the presence of a single grain, 7.7% of the total grain bill, would make such a huge difference. What is it about chocolate malt that has such an impact?

My starting water pH is 8.04, I am using 4.8gal (1.5qt per lb of grain) as strike water and mashing at 150 for one hour.
 
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All I know but can't give you the science is that the dark roasted grains will lower the PH in the mash that's why people with hard bicarbonate water are more suited to brewing stouts porters ect you can replicate this by adding bicarb soda baking soda to the mash to help raise the PH that the dark malts have offset to reach the sweet spot which I think Is a little high PH like 5.5-5.6 for dark beers.
Others will have more specific.
 
Are you 100% sure of the water make up you're using? I don't think ANY water supply has 0 alkalinity.

It's the alkalinity in the water that interacts with the acidity of the dark grains to affect mash pH.
If you wanted to be sure, you could call the city and ask what the bicarbonate/alkalinity of the water you're using is.
However, just looking at this: https://city.milwaukee.gov/ImageLib...iles/WaterQualityBasicsforMilwaukeeMakers.pdf
although it is form 2015, it is totally different that what you have in the water for your source water. Unless you're stating with RO water(?) then it would be right.
 
Are you 100% sure of the water make up you're using? I don't think ANY water supply has 0 alkalinity.

It's the alkalinity in the water that interacts with the acidity of the dark grains to affect mash pH.
If you wanted to be sure, you could call the city and ask what the bicarbonate/alkalinity of the water you're using is.
However, just looking at this: https://city.milwaukee.gov/ImageLib...iles/WaterQualityBasicsforMilwaukeeMakers.pdf
although it is form 2015, it is totally different that what you have in the water for your source water. Unless you're stating with RO water(?) then it would be right.
I'm in Milwaukie, OR, rather than Milwaukee, WI.
Here's our most recent water report that is available online:
https://www.milwaukieoregon.gov/sit...orks/page/44541/water_quality_report_2019.pdf

However, I'm sure I could call the city and get the pH, Ca+2 , Mg+2 , Na+ , Cl- , SO4-2 , and HCO3-.

Someone has loaded in a profile for "Milwaukie OR Source 3," which is where I get my water, so I was using that.
 
I'm in Milwaukie, OR, rather than Milwaukee, WI.
Here's our most recent water report that is available online:
https://www.milwaukieoregon.gov/sit...orks/page/44541/water_quality_report_2019.pdf

However, I'm sure I could call the city and get the pH, Ca+2 , Mg+2 , Na+ , Cl- , SO4-2 , and HCO3-.

Someone has loaded in a profile for "Milwaukie OR Source 3," which is where I get my water, so I was using that.
Get it directly from the city. All those values change over time.
 
Email sent. :)
Although it’s a good starting point, if you want accuracy, you should get a water test kit. Your city water changes more frequently than you would think.
 

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