Acidulated malt and 5.2 stabilizer
Posted: Wed Oct 09, 2013 8:41 am
by FSUplumber
Has any one have any experiences using acidulated malt and Five Stars 5.2 stabilizer? My first experience was a year ago. I was brewing a sour stout that had come out rather one dimensional. The wort had a very acid bite and a year later it carried on to the finished beer. Then last week end my wife and I were mashing in a sour red, she had been tasting the grains when I ask her to add the 5.2 stabilizer. She ask if she could taste that and I said sure. She. Got a god awful look on her face and said it taste just like the last batch. I stopped her from adding it and the wort came out fine. Normally sweet and no lactic bite. Both beers had the same amount of acid malt 8 oz. Am I on to something?
Thanks
Rick
Re: Acidulated malt and 5.2 stabilizer
Posted: Wed Oct 09, 2013 11:23 am
by ziggy
The 5.2 stabilizer is a sodium phosphate buffer. Sodium causes a certain sourness/bitterness at levels above ~100ppm. If your tap water already has 30ppm of sodium like mine then you add 5.2 on top of it you can easily cross that threshold. Try taking a finished beer and adding a pinch of salt. That's the low sodium sourness that you will taste. If you keep adding more it will get more sour then all of a sudden it will taste salty. That's one possibility.
I quit using the stuff a couple years ago. Now I calculate my pH on the brewer's friend calculator and it comes out great.
Re: Acidulated malt and 5.2 stabilizer
Posted: Wed Oct 09, 2013 2:20 pm
by Ozwald
According to a Kai Troester interview a couple years back on another show, 5.2 isn't a buffer at all. Never used it, never needed to. Call me old fashioned.
You can use sodium up to 150ppm without problems, it's when you have high sulfates when it becomes a problem. Sodium works similar to chloride when it comes to that 'round' flavor, so in the cases when you'd want a higher sodium level, you'd automatically be keeping your sulfates low anyhow.
Re: Acidulated malt and 5.2 stabilizer
Posted: Thu Oct 10, 2013 11:51 am
by FSUplumber
Thanks for the quick replies. I left a few things out. I brew with only deionized water, so I should be ok there. I adjust my sparge water down to 5.2 with acid. The only time I have had problems with using the 5.2 stabilizer is when I have used the acid malt. All my other ales and lager turn out very well.
Rick
Re: Acidulated malt and 5.2 stabilizer
Posted: Fri Oct 11, 2013 5:28 am
by ziggy
I've been looking into it and I think 5.2 might be a citric acid sodium phosphate buffer. That could be a lot of acid if you have acidulated malt and citric acid in there. Citric acid is the primary acid in citrus fruits like lemons and that can have a killer bite to it. I always thought it was sodium that was giving me problems years ago but now I'm thinking it might be the citric acid.
Re: Acidulated malt and 5.2 stabilizer
Posted: Fri Oct 11, 2013 11:54 pm
by Steve Urquell
Here's Kai's Water report on a sample dosed with 5.2.

Re: Acidulated malt and 5.2 stabilizer
Posted: Wed Oct 16, 2013 4:41 am
by ajdelange
5.2 is a mixture of (mostly) monobasic sodium phosphate with some dibasic sodium phosphate. It contains no acid (other than the monobasic phosphate ion). It is indeed a buffer - just not a very good one and not one that buffers to pH 5.2 but rather to around pH 6 (the Ward Labs report shows 6.1 which is pretty close to the actual value). If you are familiar with buffer chemistry you will appreciate that a phosphate buffer designed for pH 5.2 (or 6) doesn't have much buffering capacity so that lots of it will need to be used to acheive any buffering effect. You will also be aware that the malt's own phosphate will upset the balance of the two phosphate forms so that the system will tend to buffer at a different pH. I theorize that the design of this product takes that into account. Neverhteless experiments with it and mash show that it falls far short of the claim on its label especially at the recommended dose.
If you are comfortable with phosphate in your beer (and you should be as the malt is supplying quite a bit of it) but don't want the sodium then use phosphoric acid (available in safe strength at most LHBS) to set mash pH.
One other note with respect to the Ward Labs report: 5.2 does not contain any bicarbonate. They report some because of the alkalinity (which they assume comes from bicarbonate) but in fact it is the alkalinity of the phosphate ions themselves.
Re: Acidulated malt and 5.2 stabilizer
Posted: Thu Oct 17, 2013 4:14 am
by dmtaylor
After some troubleshooting efforts with a friend, I am officially convinced now that the pH 5.2 stuff is garbage. In my experience, it lends an odd Coke-like tangy tartness to the beer... AND, it doesn't work very well at all! Worthless. Throwing mine in the garbage.