Very High Attenuation with WL 001 yeast at 90%?

[jneighbors]

I've nearly always had 90% attenuation of the wort in my brewing American IPA's with the White Labs 001 Chico strain. However, this results in lower gravities in the "style" that's indicated in the software. The beer always tastes great, dry of course, and crisp, but I was wondering if should I stop short of the full attenuation to retain some of the maltose sugars?

Equation This Batch Style
Original Gravity 1.051 1.056 - 1.07
Final Gravity 1.005 1.008 - 1.014

 

[Minbari]

Short of killing the yeast, it will do what it does. Bottling early will result in over carbed beer or bottle bombs.

If you need less attenuation use a yeast with less or mash at a higher temp for a less fermentable wort

 

[Donoroto]

What he ^ said

Leaving fermentable sugars won't work very well. Even cold, the yeast will still try to eat it. Pressure builds, and sometimes the vessel fails. It could be messy, it could be dangerous.

If your mash is at a higher temperature, like 156°F, you'll get less conversion, slightly lower efficiency, but end up with a sweeter finished product. If you mash at a cool temperature, like 145°F, you'll end up with a much more fermentable wort, and a very high east attenuation.

The kinds of malt you use also affects this.

 

[jneighbors]

What he ^ said

Leaving fermentable sugars won't work very well. Even cold, the yeast will still try to eat it. Pressure builds, and sometimes the vessel fails. It could be messy, it could be dangerous.

If your mash is at a higher temperature, like 156°F, you'll get less conversion, slightly lower efficiency, but end up with a sweeter finished product. If you mash at a cool temperature, like 145°F, you'll end up with a much more fermentable wort, and a very high east attenuation.

The kinds of malt you use also affects this.

Thanks, the mash was at 149 avg.

Mash stats:
MASH:
Mash Start: 8:07 A
Target Temp °F: 150.0
Infusion Needed; 17.40 Quarts @ 159.5 °F
Quarts / Pound: 1.50
Gypsum: 1 g Ca+2 SO4• 2H2O ~0.2 tsp
Epsom Salt: 7 g Mg+2 SO4• 7H2O ~0.9 tsp
Acid Type: Lactic
Acid Strength: 88 %
Acid Amount: 3 ml
Mash pH: 5.09
Actual mash temp: 149 F Avg.
Liquor PH: 7.56

 

[Donoroto]

Thanks, the mash was at 149 avg.

Mash stats:
MASH:
Mash Start: 8:07 A
Target Temp °F: 150.0
Infusion Needed; 17.40 Quarts @ 159.5 °F
Quarts / Pound: 1.50
Gypsum: 1 g Ca+2 SO4• 2H2O ~0.2 tsp
Epsom Salt: 7 g Mg+2 SO4• 7H2O ~0.9 tsp
Acid Type: Lactic
Acid Strength: 88 %
Acid Amount: 3 ml
Mash pH: 5.09
Actual mash temp: 149 F Avg.
Liquor PH: 7.56

Could be the recipe. Can you name the grains used? Those stats don't look suspicious.

 

[Minbari]

Thanks, the mash was at 149 avg.

Mash stats:
MASH:
Mash Start: 8:07 A
Target Temp °F: 150.0
Infusion Needed; 17.40 Quarts @ 159.5 °F
Quarts / Pound: 1.50
Gypsum: 1 g Ca+2 SO4• 2H2O ~0.2 tsp
Epsom Salt: 7 g Mg+2 SO4• 7H2O ~0.9 tsp
Acid Type: Lactic
Acid Strength: 88 %
Acid Amount: 3 ml
Mash pH: 5.09
Actual mash temp: 149 F Avg.
Liquor PH: 7.56

bump that to 153-155 for the next batch and see if that doesnt give you a higher FG

 

[Sandy Feet]

I was going to post to say, try 154. Minbari beat me to it.

 

[jneighbors]

Could be the recipe. Can you name the grains used? Those stats don't look suspicious.

Amount Fermentable Bill %
10 lb Briess - Brewers Malt 2-Row 86.2%
0.40 lb Briess - Caramel Malt - 40L 3.4%
0.75 lb Crisp Malting - Extra Pale Maris Otter2 6.5%
0.45 lb Briess - Carapils Malt 3.9%

 

[jneighbors]

Thanks all, yes a higher mash temp of 155-56 would probably up the FG

 

[Donoroto]

Yes, I think that is it

 

[Yooper]

Could also try a slightly higher mash pH- I like 5.25-5.3 for my American IPAs for the best results. 5.09 seems low for a mash pH which would favor a more fermentable wort.

 

[jneighbors]

Thanks, I’ll try a higher pH. Target was 5.2, and the 3ml lactic acid was supposed to get it there from the software/grain profile. I think I’ll overshoot the target a touch next time.