Session ale, confused about mash temp vs choice of yeast

[schmurf]

I like to brew some session beers, that is low in alcohol but with quite some body and mouthfeel. Reading up on this I see, amongst others, suggestions of higher mash temperatures and choosing less attenuative yeasts. But I suppose there is a collaboration between those two, what's the best practice here...would you use just one of those methods, or both? I don't want to end up with a beer that's just too sweet.

 

[Gnomebrewer]

A high mash temp leaves unfermentable dextrins, thus a higher FG, which supposedly improves mouthfeel. It DOESN'T taste sweet though. Less attenuative yeasts leave behind some sugars that other yeasts could ferment, and these do taste slightly sweet (but not as sweet as sucrose/glucose/fructose). If you want some residual sweetness, use a less attenuating yeast. If you want mouthfeel without sweetness, boost the specialty grains and use a high mash temp.

 

[isomerization]

Residual dextrins from higher mash will (more than likely) not be perceived as sweet, while lower attenuating strains CAN leave fermentable sugars that increase perceived sweetness.

ABV will decrease in the same manner for either scenario you present.

Do not underestimate contributions from your grain bill (eg bets glucans from flaked barley and oats).

 

[schmurf]

Thanks... I guessed it was like that. But is it common to both mash high AND use low attenuating yeast? Maybe it depends on the style, but in general... for a low ABV British kind of ale.

 

[Gnomebrewer]

But is it common to both mash high AND use low attenuating yeast? Maybe it depends on the style, but in general... for a low ABV British kind of ale.

Yes, it is quite common.

 

[gregkeller]

For session beers, I've done both and think like everyone says you are doing two different things. Leaving body (not sweetness) via the high mash temp and leaving some unfermented sugars via the low attenuating yeast (something like wlp002). I really, really like it in my session IPA. Without using those two techniques, I'd end up with a very thin, watery, very intense bitter beer. By using those two techniques I end up with a very drinkable beer that to me, tastes like a true IPA but at about 3.8-4% ABV which allows me to drink a bunch of it. I've found very few commercial session IPA's that don't come across as thin and excessively dry.

 

[isomerization]

For session beers, I've done both and think like everyone says you are doing two different things. Leaving body (not sweetness) via the high mash temp and leaving some unfermented sugars via the low attenuating yeast (something like wlp002). I really, really like it in my session IPA. Without using those two techniques, I'd end up with a very thin, watery, very intense bitter beer. By using those two techniques I end up with a very drinkable beer that to me, tastes like a true IPA but at about 3.8-4% ABV which allows me to drink a bunch of it. I've found very few commercial session IPA's that don't come across as thin and excessively dry.

I agree with your comments, and will also add that high hopping rates and additional compounds that help with mouthfeel as well.

 

[gregkeller]

absolutely. I think that is also the reason a lot of IPA's and double IPA's come out too sweet, between mouthfeel from hop oils and alcohol sweetness. I work really hard to dry out my IPA's and double IPA's and really hard to retain some residual sugar and mouthfeel in my session IPA's. I think that when people first started to make commercial session IPA's they just dropped their grain bill to make a 4% IPA and they stink.