Does Using Acid Malt Make Sense?

I recently called using Acid Malt "stupid" on a brewing forum and then wondered if it really was. So I put an analytical spin on it to find out. Read on!

The first concern with acid malt is that its acid quantity can vary from batch to batch and manufacturer. So you may not be able to rely on its strength. Its a problem, but you can calibrate your usage with experience.

The next question was the economics. Acid malt is more expensive than typical base malt, but it does provide some extract. With that in mind, it appears that acid malt costs about $0.30 per pound more than high quality base malt. Using Bru'n Water to guide an acid malt addition, it appears that about 8 oz of acid malt were needed in a pale mash with 4 gallons of water. So that means that it cost $0.15 more to treat the mash with acid malt.

I then compared how much 88% lactic acid would be needed to equally acidify that same pale mash. Using prices from my local homebrew shop, it turned out that it cost $0.105 to provide that acid amount. So acid malt use costs almost 50 percent more to use than lactic acid.

But one of the benefits that acid malt users claim is that acid malt produces a fuller and more complex flavor than using lactic acid. A major reason why it is more complex is that other acids are part of the impurities in acid malt. One of the major acids in the impurity is acetic acid. So I revisited what it would cost to acidify that pale mash with both lactic and acetic acids. Distilled 5% vinegar is widely available and inexpensive. Acidifying to the same mash pH with those acids indicated that the cost drops to $0.074 for the mash. The resulting acetate ion concentration is still well under the acetate ion taste threshold (~175 ppm) and that means that the acetic acid use would only add some sort of nuance to the flavor...something similar to the complexity of acid malt.

So "stupid" may not necessarily be the proper term to describe acid malt use in brewing. But inaccurate and slightly more expensive are proper terms for acid malt use. You can still use what you prefer since the difference amounts to pennies in the typical homebrew batch size.

Enjoy!