Acetic Acid and Brewing

[cge0]

I'm talking about vinegar here, and lowering the pH of my mash.
This is my first AG and I don't have phosphoric/lactic acid laying around, and I'm assuming acetic acid, being weak, would be a good idea to lower my pH to 5.3~.
Anyone else use the poor man's way out?

 

[Yooper]

Well, I don't know if you want vinegar in your mash. Why not use 5.2 PH buffer? It's expensive at first, but a jar lasts a very long time.

 

[Lil' Sparky]

Sure, you can use it. You can either get your water report and pre-calculate the amount based on the beer you'll be brewing, or you can add it slowly, checking with pH strips or a pH meter.

But I've gotta give a +1 to yooper's recommendation on the 5.2 buffer.

 

[Dr Vorlauf]

Id recommend the 5.2 buffer. Acetic would not be my first choice... can you get citric acid?

 

[cge0]

I have lemon juice, but that's the options.
I just placed an order at a homebrew site, and I really don't feel like spending money.

 

[Lil' Sparky]

Since you don't want to spend $$ on the easy solution, before you start dorking around with the water, do you know what kind of water you have? Most areas have suitable water for AG brewing without modifications.

 

[TexLaw]

I'm with the rest of the folks. Acetic acid has a very powerful flavor and aroma that could carry over in your beer, and I don't know what quantity you would need to effectively buffer. That 5.2 stuff rocks. Even though the jar is expensive, you only need one teaspoon per five gallons of water you treat.

I think you would do better to take your chances and let the grain lower the pH than to add acetic acid. If you don't have very alkaline water, you'll probably be fine.


TL

 

[the_bird]

Well, the pH of your water isn't what's really critical - but you've got to have a way of knowing what your pH is during the mash (test strips or a meter) before you want to be adding anything to adjust it. Remember, different recipes have a different impact on pH (dark grains have an impact, but I can't remember which direction).

The way that German brewers adjust mash pH in the context of the Reinheitsgebot was to use acid malt (which contains a lot of lactic acid).

 

[Kaiser]

I'm talking about vinegar here, and lowering the pH of my mash.
This is my first AG and I don't have phosphoric/lactic acid laying around, and I'm assuming acetic acid, being weak, would be a good idea to lower my pH to 5.3~.
Anyone else use the poor man's way out?

Do you have a water report? If this is your first AG you may worry about a problem that you may not have.

Kai

 

[the_bird]

I'll add another vote for the pH buffer, too. If you're anything like me, it's REALLY cheap since you'll forget it half the time!

 

[cge0]

I use RO/DI water for brewing.
It reads close to 7.0

 

[e lo]

Adding straight acid solution probably isn't the best way to adjust your mash temp, because, while it will change the pH, it won't provide any significant buffering. Plus, as mentioned above, do you really want your beer to smell and taste like vinegar?

 

[FlyGuy]

I'll agree that vinegar is not the way to go.

I asked a similar question a while ago:
https://www.homebrewtalk.com/showthread.php?t=43118&highlight=citric+acid

Citric acid seemed to be the winning solution.

 

[sause]

Whats your recipe? Most beers you won't have to worry about it. Unless your going for a Pilsner you shouldn't. And if you are doing that you can do an acid rest. That's how german brewers do it.

 

[Yuri_Rage]

I'd rather add nothing than add vinegar to my mash. While it will lower the pH, acetic acid's flavor is...awful. Nothing will ruin beer quicker than an acetobacter infection...I have to assume the same about acetic acid.

In order of preference, the options presented so far are:
pH 5.2
acid malt and/or an acid rest
lactic acid or citric acid
do nothing

The latter two options weigh almost equally in my mind.

 

[david_42]

Should work fine, if you like sour beers that smell like vinegar. It doesn't decompose until 440C, so whatever you put in the mash ends up in the beer.

 

[the_bird]

I'll say it again, because *I* think it's the most important thing....

If you don't KNOW what the mash pH is, don't futz with it! The buffer is fine, but otherwise, I think it's a terrible idea to add acids to your mash without first confirming whether you are, in fact, too high. You're more apt to do harm than good.

Worst-case, if you do nothing (not even using the buffer), your efficiency might suffer a wee bit. Nothing to worry about too much, especially on your first batch.

One thing that tripped me up last time, when I finally started checking, was that the mash pH will read differently at mash temps versus room temps, so adjust accordingly.