Lactic acid's effect on fermentation

[RedRyderr]

Wodering if lactic acid could cause a high final gravity reading? Used some for the first time and I had a batch come out with a real high FG reading. What would normally be 1.010 for this beer came out at 1.030. The acid is the only thing I did different on brew day, and for the fermentation schedule.

Not sure on actual PH readings, don't have a PH meter. Relying solely on software and taste buds up to this point.

 

[Dgallo]

Wodering if lactic acid could cause a high final gravity reading? Used some for the first time and I had a batch come out with a real high FG reading. What would normally be 1.010 for this beer came out at 1.030. The acid is the only thing I did different on brew day, and for the fermentation schedule.

Not sure on actual PH readings, don't have a PH meter. Relying solely on software and taste buds up to this point.

Brewers yeast doesn’t have any issue in a typical “sour” environment. Most strains can easily ferment in the low 3s.

what is possible is that your mash ph was too low and you had enzyme conversion issues.

With that said, what are you using to measure your gravity? Hydrometer or refractometer?

 

[RedRyderr]

Hydrometer for gravity readings. PH meter is on my short list of must haves..

 

[myndflyte]

What did you use for souring? Unless you used something different that takes the pH really low, yeast should be fine. What was your mash temp?

 

[marc1]

What were the details for this batch? How much grains, water, lactic, etc?

 

[mabrungard]

Lactate ion is utilized as a nutrient by yeast and a low mashing pH tends to produce a more fermentable wort due to proteolysis. So it’s unlikely that lactic acid use would cause poor attenuation.

 

[RedRyderr]

Thanks for the replies. I'm still dialing in my process brewing with pure RO water. Thanks @mabrungard - I've been using your spread sheet!

This was my 18th batch of the same recipe. Wheat beer. 16 lb grain bill, 5 gal batch size. (7.25 2-row, 7.25 Wheat, 0.75 Munich, 0.75 Carapils). Fermenting with Bell's house yeast. Always finishes up around 1.008 - 1.010. ABV typically between 6.5 and 7.0. I added 1 tsp each of Calcium Chloride and Lactic Acid to the strike and sparge waters (roughly 5 gals water in each. So 2 tsp each CC and acid to 10 gal total). Mash temp ended up at 150. A bit lower than I was shooting for.

Possible too, I suppose, that it just wasn't done fermenting? I don't usually take successive gravity readings to confirm complete fermentation. Usually just cold crash and fine after about a week and half. Keg right around the two week mark. Been working good so far. May need to rethink that?

 

[Jtvann]

Also depends on the amount of lactic acid used I think. Are we talking 5-10 ml for a 5 gallon batch?

As a reference I just made a sour with 14mL in the mash and 30mL post boil to bring it down to 4.5 in a 12 gallon batch.

Mash pH could heavily affect it, pH post boil, not so much.

 

[RedRyderr]

I treated 10 gallons of water with just under 10 ML of Lactic acid.

 

[marc1]

Thanks for the replies. I'm still dialing in my process brewing with pure RO water. Thanks @mabrungard - I've been using your spread sheet!

This was my 18th batch of the same recipe. Wheat beer. 16 lb grain bill, 5 gal batch size. (7.25 2-row, 7.25 Wheat, 0.75 Munich, 0.75 Carapils). Fermenting with Bell's house yeast. Always finishes up around 1.008 - 1.010. ABV typically between 6.5 and 7.0. I added 1 tsp each of Calcium Chloride and Lactic Acid to the strike and sparge waters (roughly 5 gals water in each. So 2 tsp each CC and acid to 10 gal total). Mash temp ended up at 150. A bit lower than I was shooting for.

Possible too, I suppose, that it just wasn't done fermenting? I don't usually take successive gravity readings to confirm complete fermentation. Usually just cold crash and fine after about a week and half. Keg right around the two week mark. Been working good so far. May need to rethink that?

Nothing in your additions jumps out as being insane.