Alkalinity and Lactic Acid

[Moneyjacket]

My water report is as follows,
pH 7.4
Ca 30
Mg 10
Na 7
Cl 5
SO4-S 3, so 9 SO4
Bicarbonate 148
Alkalinity 122

My next planned brew is Biermunchers Centennial Blonde, which is a pretty light beer, beersmith says 3.6 SRM. I've been reading Ajdelange's posts here and it seems that he would tell me to dilute my water down to 20 Alkalinity or less. I'm wondering if just using lactic acid to lower my mash ph would be a suitable alternative since I would rather not buy water. According to estimations by ezwatercalculator, I would be adding 3ml of 88% to my mash to get it to 5.2, I will be checking with a meter. I also wonder if I should use the lactic acid to lower my sparge water from 7.4 to 6? Thanks in advance for any input.

-Money

 

[Nateo]

I use lactic acid all the time to lower my mash pH. I lower my sparge to <5.8. Your water looks pretty good, and I agree it's a bit silly to buy water.

IIRC, Prof. Delange recommended brewing beer that works with your water, instead of making drastic contortions to make your water suitable. I agree in theory, but not enough to go out and buy water.

So the long and short of it is, will you need to acidify your mash? Yes. Will the beer turn out well even though your RA was a bit high? Yes. Will the beer be the best possible beer you could make? Probably not, but I wouldn't worry about it.

 

[ajdelange]

It's fine to use acid to knock out alkalinity but there is a downside. Every milliequivalent of alkalinity you remove (this water has 122/50 = 2.4) is replaced by 1 milliequivalent of the anion of the acid you used. So if you knocked out all the alkalinity you'd replace the 2.4 mEq/L alkalinity with 2.4 mEq Lactate (same deal for sulfuric or hydrochloric). This should be kept in mind. Obviously everything is fine as long as you don't taste the lactate or dislike the effects of lots of chloride or sulfate.

The reason I advocate dilution with RO water so readily these days is that it is so readily available. Home RO units are sold at home improvement stores for a little over $100 and every supermarket and healthfood store seems to have an RO machine vending RO water for half a buck per gallon.

 

[Moneyjacket]

Thanks for the reply's. Thats pretty much what I expected/hoped to hear. I read somewhere that lactic acid would sour the beer, but it wasn't too noticeable until you had around 2ml per gallon which I would be way below. I'm a little confused about mention of the affects of lots of chloride or sulfate since my water only has 5 and 9 ppm's, do bicarbonites or alkalynity contain those?. Eventually as my brewery gets more intense I will probably end up with a RO unit, but as of now I have pumps, conicals, grain mills,ferment chambers and such dominating the top of my wish list. It sounds like the lactic acid will be a big improvement, but ill fill up my 5 gal jug with some distilled water one of these days and brew a comparison batch as well. I really appreciate the advice.

-Money

 

[ajdelange]

What I meant was that if you use sulfuric acid to remove 2.4 meq/L alkalinity you will wind up with 2.4 meq/L sulfate in its place. This is 115 mg/L which would be enough to trash a delicate lager or helles. Also, if you use HCl to remove 2.4 meq/L you will replace it with 2.4 meq/L (85 mg/L) which some might find excessive but most would probably like.

 

[SpanishCastleAle]

...and every supermarket and healthfood store seems to have an RO machine vending RO water for half a buck per gallon.

FWIW, around here it's 25 cents per gallon so enough for an entire 5+ gal batch is ~$2.25. Since I do pay for my chloraminated tap water in both water AND sewage fees and would have to use campden anyway, for some of us using the store-bought RO isn't much if any more expensive.

 

[Nateo]

I live downtown so I don't need to own a car. 5 gallons of water is pretty darn heavy to carry on my bike, or the bus. So there is a practical component to my situation.

 

[Moneyjacket]

I see what you were saying now Aj, I suppose I will deal with the lactate rather than sulfate or chloride.
I pay a set amount per 3 months for my water, doesn't matter how much I use and it's not chlorinated. I live 25 minutes away from the nearest supermarket, so unless I want to pay 2.50 per gal of water at the little neighborhood store, it's about a 1 hour adventure to go get my 5 gal jug filled up. Though I could just throw it in the car and fill it up whenever I'm already in town. Mostly just a convenience thing, though I will definitely try the dilution method one of these days, always striving for that perfect beer.

 

[PaulHilgeman]

I regulularly use 4ml in a 5 gal batch of all pilsner malt and it is so much easier and the taste is fine to me vs. diluting etc.

If I was going to do a bo-pils I would do it differently, but I much prefer north german pils.

 

[Kaiser]

It's very common in German brewing to use lactic acid. I myself face used up to 4% acid malt in my recipes w/ a noticable sourness. In a 5 gal batch with 4kg of malt this is about 5g lactic acid. So 3 ml should be fine.

I actually think that all very light beers benefit from 2% acid malt just because their mash pH even in 0 residual alkalinity water is around 5.7-5.8.

A.J., is this something that matches your experience?

Kai

 

[ajdelange]

Yes. I usually use 3% in Pils, Vienna, Bock, Kölsch made with RO water (supplemented with some CaCl2) and generally wind up with mash pH's 5.4 - 5.5.

 

[Moneyjacket]

do lactic acid and acid malt have basically the same positive and negative affects? I'm wondering if there's a point to using acid malt if you're going to also use lactic acid.

 

[ajdelange]

Sauermalz and, presumably, Sauergut would have some flavors beyond just the lactic flavor of bottled lactic acid and I prefer Sauermalz for that reason (and it's a bit easier to handle).