Off Flavor - Could it be lactic acid?

[Sidman]

I recently brewed a 10 Gallon all grain batch following the Cream of the Crop recipe. I used RO water and when entering the recipe into beersmith it recommended a 9.4ml lactic acid addition for the mash. I put in a little under 2 tablespoons to my mash water. I hit OG and FG just fine and the beer has nice taste up front but then you're left with a tart back end note that is off putting. I am wondering if the lactic acid could have caused this and more importantly is there a remedy. I was thinking of a citrus or even grapefruit addition to mask that. At this point the beer is keged. Any suggestions?

 

[BeerAddikt]

2 Tbsp of lactic acid is about 1oz. That is enough to provide a subtle sour note. 9.4ml is less than a Tbsp (about .64 Tbsp) so you definitely used a heavy hand.

You could certainly try to add citrus, in particular orange, to mask the sour note. It may even turn out amazing. Outside of orange I'm not sure of any other citrus fruits that are regularly used in a cream ale. Good luck.

 

[Sidman]

You could certainly try to add citrus, in particular orange, to mask the sour note. It may even turn out amazing. Outside of orange I'm not sure of any other citrus fruits that are regularly used in a cream ale. Good luck.

Thanks for the input. Any suggestions on adding the orange.
? Fruit in the keg, add orange juice or concentrate? I've even seen some recipes that used flavor oils commonly used in baking. Any have a suggestion for adding that to kegged and carbed beer?

 

[Silver_Is_Money]

This being a 10 gallon batch, I doubt that by adding 9.4 ml you have added nearly enough 88% lactic acid to reach the flavor threshold. Typical advice for light lagers is to add up to 3% by grist weight of acidulated malt. Assuming that your grist weight is 23 pounds, that would mean the addition of 11 ounces of acidulated, which is about the acid equivalent of 9 ml of 88% lactic acid. And that is for a delicate flavored light lager.

In Germany acidulated malt is the only legal means by which to achieve a normal mash pH. Do you taste lactic acid in light colored German lagers (where its flavor should be most evident)?

Brulosophy recently added 19 ml of 88% lactic acid to the mash (strike water) of a 5 gallon batch, and their panel of roughly 24 taste testers could not statistically distinguish it from an otherwise identical batch that did not have the lactic acid addition. That would translate to 38 ml of lactic acid for a 10 gallon batch. They mashed the batch (successfully) at 4.45 pH. The control batch mashed at 5.3 pH. Both finished beers had nearly the same pH in the end.

 

[mabrungard]

I guess its possible to need that much lactic, but that does seem to be a bit high when starting with RO water. Was that 88% lactic?

Since most Exbeeriment tasters aren't trained or evaluated for their tasting capabilities, I don't put a lot of weight in their findings. They are just one data point. But the testing does lend credence to the fact that most beer drinkers can't really tell the difference in beer flavor. So don't read too much into that test that said the an intentionally overacidified beer tasted the same.

PS: The other (and preferred method for German brewery acidification is via soured wort (saurergut).

 

[Yooper]

Two tablespoons of lactic acid must be around 10 ml, give or take, I'd think.

That may be above the flavor threshold in RO water. It would probably reduce the mash pH greatly but I didn't use a spreadsheet to see.

I tried lactic acid in my tap water, and with my high bicarbonate (228 or so if I remember correctly), 1 ml per gallon was not detectable but more than that was. So I'm thinking that if I tasted it in my alkaline water above 1 ml per gallon, then it would be above the taste threshold in RO water, in addition to driving the mash pH low.

 

[Silver_Is_Money]

I didn't catch that the OP used RO water. I can't imagine any grist requiring that much lactic acid for a batch mashed in RO water.

 

[beermanpete]

1 tablespoon = 15 mL so you added about three times the recommended amount of lactic acid. 9.4 mL = 1.9 teaspoons so 2 scant teaspoons would be pretty close. For a higher level of accuracy you need a pipette or perhaps a small graduated cylinder.

 

[Yooper]

1 tablespoon = 15 mL so you added about three times the recommended amount of lactic acid. 9.4 mL = 1.9 teaspoons so 2 scant teaspoons would be pretty close. For a higher level of accuracy you need a pipette or perhaps a small graduated cylinder.

Oh, my gosh that's right! I was thinking two TEASPOONS was too much. Two teaspoons is about 10 ml. Two TABLESPOONS is like 30 ml- and that would be quite a lot in a mash, but with RO water it would be a ridiculous amount assuming an 88% lactic acid.

 

[BeerAddikt]

Brulosophy recently added 19 ml of 88% lactic acid to the mash (strike water) of a 5 gallon batch, and their panel of roughly 24 taste testers could not statistically distinguish it from an otherwise identical batch that did not have the lactic acid addition. That would translate to 38 ml of lactic acid for a 10 gallon batch. They mashed the batch (successfully) at 4.45 pH. The control batch mashed at 5.3 pH. Both finished beers had nearly the same pH in the end.

What kind of beer was it? A cream ale has very little to mask a sour flavor. He added about 29ml. I've used 88% lactic acid before and you are definitely going to taste that but it won't be overwhelming, just a little twang.

 

[BeerAddikt]

Thanks for the input. Any suggestions on adding the orange.
? Fruit in the keg, add orange juice or concentrate? I've even seen some recipes that used flavor oils commonly used in baking. Any have a suggestion for adding that to kegged and carbed beer?

Since it's too late to add during fermentation you could just add pure orange extract but start light and add to taste.

https://www.olivenation.com/orange-extract.html

 

[Silver_Is_Money]

What kind of beer was it? A cream ale has very little to mask a sour flavor. He added about 29ml. I've used 88% lactic acid before and you are definitely going to taste that but it won't be overwhelming, just a little twang.

The Brulosophy batch was a lager. Their grist was 10 lbs. of Pilsner malt, and 1 lb. of flaked oats. Not much there to prevent any off flavors from shining through.

http://brulosophy.com/2017/01/30/wa...he-impact-of-low-mash-ph-exbeeriment-results/

The bottom line is that the OP added way more than he thought he added. That changes everything. I believe there are 3 teaspoons in a tablespoon. And he added 2 tablespoons. That's 6 teaspoons of 88% lactic acid.

One lesson we can learn from this plus Brulosophy though is that you can successfully mash at ridiculously low pH's.