Question about how mash temp and yeast selection affect body if fg is the same

So I’ve been thinking about this for a while now and haven’t come across an answer after searching the forums. I have a recipe that starts at 1.068 and ends at 1.014 using 1318 mashed at 148F. I have recently come across a more attenuative strain with very similar if anything cleaner flavor profile wlp007. My question is if I swap out the 1318 for the 007 and increase my mash temp to 150F beer smith projects the same 1.014 fg. What will the difference in flavor be besides the slightly cleaner less estery flavor profile from the 007? How will this affect the body or will it at all???

Final gravity predictions are pretty much just a SWAG.

You can find out how you perceive the differences in these yeasts by brewing a batch of wort, splitting it, and fermenting each half with one of those yeasts.

I do this often to see if I like one yeast over the other in a style of beer.

Assuming the FG prediction is accurate, the beer will have a little more alcohol which might slightly affect flavor and mouthfeel.

However, the post above is completely right. FG predictions are a total guess and you’ll need to experiment to dial in accommodating a different yeast.

I have brewed this several times with the 1318 and I do in fact hit 1.014. How would there be more alcohol in one if both start and end at the same gravity’s? And if I split the same batch of wort and use a different strain in each part the 007 will finish lower which defeats the point of my question. Anyone else care to chime in?

Yep - These guys are right. FG estimates are a complete WAG, and vary with grist, mash schedule, strain, etc. If your beer with 1318 finishes at 1.014, great. But there’s no guarantee you could necessarily distinguish it if it finished a point or two higher or lower. Nor can we tell you how you’d perceive it with 007. The suggestion to compare with a split batch is a good one.

The only way to know is to do a split batch yourself.
On attenuation and mash temp, I’m listening to an episode of Basic Brewing Radio right now where Sean Terrill (sp?) is on discussing his data on mash temp vs attenuation for three strains (one lager, one Belgian, and the Anchor Liberty strain).  The Belgian (d’Achouffe?) strain behaved as brewing dogma suggests it would, lower attenuation at higher mash temp.  The lager strain didn’t have enough data points, but is kind of flat in the middle of mash temp range, and lower attenuation on either extreme end.  The American strain threw dogma out the window and had the same degree of attenuation regardless of mash temp.  I could be slightly misremembering things, but you can find the data on his blog.  So moral is don’t assume adjusting mash temperature will change attenuation.  It might not.

On to the other part of your question… I just bottled a split batch 95%MO/5% light crystal (~C40) fermented with S-04 vs 007.  You’d think 007 would finish lower, but they both finished at the same FG.  Tasting the hydrometer samples, I swear that S-04 had more mouth feel than 007.  Could be glycerol.  Could be a small amount of diacetyl adding to the feel.  Could be different sugars left in the beers even though FG is the same.  Who knows?  But there’s more to mouthfeel than just unfermented sugars.  In fact, those Brulosophy experiments where they test two mash temperatures and get beers well over 1% abv different, yet are seemingly identical to tasters would support this.

Sorry.  I know you wanted and answer other than “brew a split batch”.

No Todd you are a champion this is more of what I’m looking for thank you for sharing I am definitely going to look into both references you mentioned and I now have a little better understanding of how things may work out in the real world. I plan on doing some experimenting but the batches coast me approx $70 a piece, just trying to get some clarification before attempting.

Yes, yeasts like 3711 are said to have super high high attenuation, but decent mouthfeel due to glycerol production. Not what he asked per se, but there is that.

Sean Terril is active on here, maybe he will see this.

Another variable that needs to be included here is: time.

While temperature is known to favor certain enzyme activity, those enzymes need time for their work. I believe that fermentability and attenuation can be strongly influenced by shortening or lengthening the mashing duration.

I see it! Don’t know that I can summarize any better than what’s been said though. ;D

I’ve seen that firsthand at a brewery that had an under-sized grain mill. It would take 60-80 minutes to mash in for big beers, and even jumping immediately into vorlauf (i.e. no mash “rest”), there was nothing we could do to drive down attenuation.

They probably were using North American 2-row with high DP, right?

Or 1450.  Same attenuation as 1056 but but much bigger mouthfeel.

Primarily pilsner malt, but same principle.

As far as temperature mashing at 148 or 150 probably won’t make much difference. Get it up to 155 range you will probably see a difference