Numbers Discrepancy

[WBB]

So I am going to be brewing a saison DuPont clone I saw in beer and brewing magazine. However when I put the information into a brewers friend recipe calculator, the numbers are totally different.

Magazine article numbers:
Og 1.065
Fg 1.012
Ibu 28
Abv 6.5

Brewers friend numbers:
Og 1.072
Fg 1.015
Ibu 19.22
Abv 7.5

Which numbers are correct? Why are they so different?

 

[chickypad]

The calculations depend on things like efficiency (if all grain), volumes, etc. so you need to adjust for all these settings. Whenever you are using someone else's recipe you should always correct for your own system anyway, which means you may need to adjust the ingredients to hit your target.

 

[dmtaylor]

Need recipe to know for sure. Some software is better than others. Also key information is the yeast strain. For example Belle Saison and 3711 yeasts will take the FG down to 1.002 every time regardless of any software or magazine article, while other yeasts probably will not.

 

[IslandLizard]

As @chickypad said, you need to adjust recipes for your own system, processes, and methods.

If this is an all grain brew, most magazine recipes (but not all) are typically formulated for 75% mash efficiency. A higher mash efficiency such as a BIAB @85% will require around 10% less grain, otherwise your gravity will be 10% higher. 1.072 vs. 1.065. Then there are other brewhouse efficiencies... Like how much wort is left behind in the kettle or fermentor.

As @dmtaylor said, one yeast will attenuate more than another.

There's nothing wrong with using a different yeast, just make some adjustments, or ride with the slightly lower or higher FG. Yeast is done when it's done, there's not much you can change about that! I've ended up with an FG of 1.016 rather than a predicted 1.012. I wasn't all that happy, but the beer was still very drinkable.

Now the difference in IBUs you calculated are a bit more puzzling.

You calculated a 30% reduction in IBUs over the original recipe, that's a lot. Did you use the same bittering hops? Is the original boiling longer? Make sure you keyed in the AA% off the hops you are actually using. They vary quite a bit amongst crops and sources. Then adjust the amounts (and/or timing) to match the original IBUs a bit closer.

You can see clearly that cloning a beer or even brewing one from a given recipe is not exact science. That's why we brew, while making small changes here and there, we still love all the results we get.

 

[IslandLizard]

Just reread, a Saison with a predicted FG of 1.012?
That sounds way off. Any Saison recipe not in the single digits (definitely above 1.008) is already suspect.

 

[WBB]

Here is the link to the recipe.

https://beerandbrewing.com/belgian-saison-in-the-style-of-saison-dupont-recipe/

I guess I don’t understand what it means to adjust the recipe for my own system. Do you mean I just can’t use the recipe and all the same amounts on my own system?

I brew all grain and use a 3 vessel system and batch sparge. My mash tun is a HD 10 gallon orange water cooler, I have a 10 gallon mega pot 1.2 for my HLT and a 15 gallon mega pot 1.2 for my kettle.

So I also just noticed, in the magazine recipe, the AA for the EKG is 6.3% and the Styrian Goldings is 1.5%, but when I put them into the recipe builder in brewers friend, the AA’s are 5% and 5.5%, respectively. So would that cause number discrepancies?

 

[chickypad]

If your efficiency is exactly the same as the recipe calls for and your volumes are exactly the same then yes you can just use those amounts. That is often not the case though, so you should get used to plugging in recipes and adjusting for your own numbers. When I say adjust to your system I mean that you need to learn what your typical mash efficiency is, what your system losses are like deadspace, trub, etc. That recipe you linked lists brewhouse efficiency, which I think is even harder to try and match as different systems can have very different losses.

As far as volume, one person might figure on 5.5 gals into the fermenter to get 5 gals packaged when finished, some just figure their recipe for 5 gals into the fermenter and accept the trub losses at the end. Even with the same efficiency that is a 10% difference in ingredients needed for those two different volumes.

Hops AA% will vary year to year and farm to farm, so you always should plug in the actual AA of the hops you are using as Lizard mentioned above. Those differences will absolutely cause discrepancies in IBU's.

 

[beermanpete]

That article has errors. The efficiency is labeled "brewhouse" but based on the other data must be mash/sparge efficiency. The final volume is likely the finished beer volume and does not include kettle losses.

12.75 lbs malt with an average extract potential of 35 pppg at 80% in 5.5 gallons yields a S.G. of 1.065. When the 0.5 gal. kettle losses are included the brewhouse efficiency becomes 72%.

The hops AAU should read AA or not have a percent sign. If you use hops with a different AA value, say 7.0% instead of 6.3% you adjust the weight by the ratio of the two. For example, 6.3/7=0.9. Multiply the 1.0 oz by 0.9 to get the weight needed for the 7% AA hops.

The IBU calculations can be done with several popular formulas. Unfortunately, each one returns a diiferent result. Since we do not know which one was used for this recipe the best that can be done is to use the same AAU as indicated and hope for a good result.

 

[dmtaylor]

Look at your packs of hops to find out what the actual alpha acid (AA) percent is. The 1.5% in the recipe is silly-low.

Looks like they probably used Tinseth method of IBU calc, but at this low amount of IBUs in the 20s it's probably not critical to be honest.

For the 3724 yeast, the FG of 1.012 might be right. If I recall correctly, that strain might not be diastaticus.

We're just arguing about stuff that ultimately won't matter if you don't care about details and just want to brew it. If you don't care, and just brew it anyway, it will still turn out good.

And getting back to the OP's original question..... It would appear that either Brewers Friend is wrong, or your use of the software was not perfect.

 

[IslandLizard]

I would stick to some of the (proven) Saison Dupont recipes/guidelines here on HBT itself, such as this one. Do a search for the others, e.g., saison dupont clone (in Google).

The malt bill is very simple: 100% Belgian Pale Malt (Dingemans), but could be tweaked a little. There's no wheat in it.

You need to control your ferm temps, ramp them up slowly in the beginning, and being able to keep them high and constant when needed (without dropping). Don't expect this beer to be done quickly with WLP565/WY3724 (Dupont strain), they tend to stall around 1.030 for 2 weeks or longer before resuming. You'll need a large, healthy yeast starter and good aeration to be able to complete the fermentation. The yeast gets better on her 2nd and subsequent rounds.

 

[Qhrumphf]

That recipe is written like sh**, wow. Those numbers simply don't add up.

And 1.5 is low, but for continental hops the alpha trend has been going down for a while. I got a lot of 1.8% AA Hallertau and have used 1.1% Strisselspalt. So that may have been the case.

The way the recipe is *kind of* listed (ie references but doesn't use) makes hop conversion easy. AAU- alpha acid units. Multiply weight by AA percentage. That number stays the same. You could leave all the ratios the same and remath that way. My preffered method is to leave late hops as w/v ratio (ie they don't change even if alphas change) and then adjust the bittering addition up or down for changing alphas. I find it better preserves the character. But that'll require a lot more math.

 

[specharka]

Here is the link to the recipe.

https://beerandbrewing.com/belgian-saison-in-the-style-of-saison-dupont-recipe/

I guess I don’t understand what it means to adjust the recipe for my own system. Do you mean I just can’t use the recipe and all the same amounts on my own system?

I brew all grain and use a 3 vessel system and batch sparge. My mash tun is a HD 10 gallon orange water cooler, I have a 10 gallon mega pot 1.2 for my HLT and a 15 gallon mega pot 1.2 for my kettle.

So I also just noticed, in the magazine recipe, the AA for the EKG is 6.3% and the Styrian Goldings is 1.5%, but when I put them into the recipe builder in brewers friend, the AA’s are 5% and 5.5%, respectively. So would that cause number discrepancies?

That’s a terrible saison DuPont recipe from CB&B. It might be a decent saison recipe, I wouldn’t know, but that’s nothing like saison DuPont.

Saison DuPont is well renowned for being an extraordinarily simple recipe, just Pilsner malt, EKG hops, and the DuPont house yeast strain. The key is slowly ramping up mash temperatures from 131F to 162F over 90 minutes to build dextrins and develop head-retention. Shoot for 28 IBU @ FWH and another 2-3 IBU @ flameout. Pitch the yeast around 65-70, allow it to bloom under open fermentation conditions (no back pressure), then ramp up the temperature after high krausen to 85+ and pray the yeast gods show you favor.

 

[WBB]

Thanks all for the responses!

I’m still kind of a rookie at this, only about 4 or 5 brew sessions under my belt. I’ve been trying to get a process down to a point where I can say, hey I’ve x number of hours because the wife, kids, and work aren’t expecting my attention, so I can brew something.

So far what I’ve brewed has been well received.

I’ve been doing mainly IPAs, but would like to start doing other styles. The next one I want to do is a saison. I’ve been building starters of 3724 and 3711, so either will be ready for the show when the time comes.

@IslandLizard, I read thru that link and picked up a few points from it. I don’t think I’ll be following the recipe from the magazine anymore.

I guess I’ll just take a gander at some more recipes and information out there and compile into an experiment and see what happens. If it tastes like crap, I’ll tweak.

 

[corax]

It's in need of a new edition, but I found Ray Daniels' book Designing Great Beer to be a great help in understanding how all the numbers fit together, and how to modify recipes to work in different systems -- or better yet, how to design your own recipes.