German Acidulated Malt for Mash pH Adjustment and Sour Beer
Adjust mash pH naturally with Weyermann Acidulated Malt. Produced in Bamberg, Germany from high-quality German brewing barley, this pale specialty malt contains natural lactic acid derived from unhopped beer wort.
Also known as acid malt, sour malt or Sauermalz, it provides brewers with a simple grain-based method of lowering mash and wort pH. Correct mash pH can improve enzymatic conversion, extract performance, lautering and overall flavour balance.
Weyermann advises that adding approximately 1% Acidulated Malt to the grain bill may reduce mash pH by around 0.1. Use up to 5% for mash-pH correction or up to 10% in sour beer recipes requiring a more noticeable fruity acidity.
Why You’ll Love Weyermann Acidulated Malt
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Premium German acidulated brewing malt
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Produced by Weyermann® in Bamberg, Germany
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Made from high-quality German brewing barley
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Contains natural lactic acid derived from unhopped wort
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Provides a grain-based method of adjusting mash pH
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Can improve mash-conversion conditions
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Helps brighten and balance beer flavour
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Very pale 2–5 EBC colour
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Fruity and lightly acidic sensory profile
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Suitable for pale and dark beer styles
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Ideal for Pilsner, Helles, wheat beer and sour beer
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Maximum recommended addition of 5% in standard beer
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Suitable for up to 10% in sour beer
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Freshly packed to order by Border Brewing Supplies
Flavour Profile
At normal mash-adjustment rates, Weyermann Acidulated Malt has little direct flavour impact. Instead, its main purpose is to lower mash pH and help the complete recipe produce a cleaner, brighter and more balanced result.
Higher additions create a more noticeable fruity acidity and gentle lactic tartness. It can support sour beer recipes, but Acidulated Malt alone will not generally create the intense acidity of a properly kettle-soured or mixed-fermentation beer.
Colour: Very pale straw to light gold
Flavour: Mild grain with fruity lactic acidity
Aroma: Fresh malt with a light acidic note
Acidity: Low to moderate, depending on usage
Enzyme Activity: Benefits mash enzymes by helping optimise pH
Primary Purpose: Mash and wort pH adjustment
Typical Beer Styles
Weyermann Acidulated Malt is suitable for:
| Lager and Traditional Styles | Wheat, Sour and Specialty Styles |
|---|---|
| German Pilsner | Berliner Weisse |
| Munich Helles | Gose |
| Kölsch-style Beer | Witbier |
| German Leichtbier | Hefeweizen |
| Pale Kellerbier | American Wheat Beer |
| Dortmunder Export | Saison |
| Festbier | Farmhouse Ale |
| International Pale Lager | Fruit Sour |
| American Pilsner | Catharina Sour |
| India Pale Lager | Sour IPA |
| Helles Bock | Low-Alcohol Beer |
| Schwarzbier | Alcohol-Reduced Beer |
Acidulated Malt can also be used in Pale Ale, IPA, Porter, Stout and other styles whenever the mash requires pH correction.
Product Specifications
| Specification | Value |
|---|---|
| Maltster | Weyermann® |
| Country of Origin | Germany |
| Malt Type | Acidulated / Sour Specialty Malt |
| Grain | German brewing barley |
| Acid Source | Natural lactic acid derived from unhopped wort |
| Colour | 2–5 EBC |
| Lovibond | 1.2–2.3°L |
| Flavour | Fruity and acidic |
| Typical pH Effect | Approximately 0.1 reduction for each 1% of the grain bill |
| Maximum Standard Usage | 5% of the grain bill |
| Maximum Sour-Beer Usage | 10% of the grain bill |
The actual effect on mash pH depends on brewing-water alkalinity, the complete grain bill, mash thickness and the buffering capacity of the mash.
Brewing Tips
For mash-pH adjustment, add Weyermann Acidulated Malt directly to the grain bill and mash it with the other crushed grain.
As a general starting point:
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1% of the grain bill: approximately 0.1 reduction in mash pH
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2% of the grain bill: approximately 0.2 reduction
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3% of the grain bill: approximately 0.3 reduction
These figures are approximate. Measure mash pH using a properly calibrated pH meter rather than relying solely on a percentage calculation.
For most standard beer styles, use approximately 1–3% of the total grain bill. Weyermann recommends a maximum addition of 5% for standard beer and 10% for sour beer.
Mash-pH readings should be taken from a cooled sample, ideally around 10–15 minutes after mash-in. A common room-temperature target for many beer styles is approximately pH 5.2–5.6, with the exact target depending on the recipe and brewing process.
Acidulated Malt is particularly useful in very pale grain bills brewed with moderately alkaline water. Dark roasted grains naturally lower mash pH, so dark beer may require less Acidulated Malt or none at all.
Brewing software can estimate the required addition, but actual water alkalinity and malt variation mean the result should always be confirmed with a pH measurement.
Frequently Asked Questions
What is Weyermann Acidulated Malt?
Weyermann Acidulated Malt is a pale German brewing malt containing natural lactic acid derived from unhopped beer wort. It is used primarily to lower mash and wort pH.
Is acidulated malt the same as sour malt?
Yes. Acidulated malt, acid malt, sour malt and the German term Sauermalz all describe malt treated to contain lactic acidity.
How much does Acidulated Malt lower mash pH?
Weyermann advises that approximately 1% of the grain bill may reduce mash pH by around 0.1. This is a guideline rather than a guaranteed result because water alkalinity and the complete recipe affect mash pH.
How much Acidulated Malt should I use?
Approximately 1–3% is common for mash-pH adjustment. Weyermann recommends no more than 5% in standard beer or 10% in sour beer.
Does Acidulated Malt make beer taste sour?
At normal mash-adjustment rates, it generally has little noticeable sour flavour. Higher percentages can add fruity lactic acidity and a more obvious tart character.
Can Acidulated Malt make a sour beer?
It can contribute acidity, but it will not normally create the depth or low final pH of a kettle-soured or mixed-fermentation beer by itself. It is better used to support sourness or make a gentle tart beer.
Does Acidulated Malt replace lactic or phosphoric acid?
It can be used instead of liquid acid for mash-pH adjustment. Acidulated Malt is easy to incorporate into the grain bill, while liquid lactic or phosphoric acid allows more precise dosing and can also be used to treat sparge water.
What is the difference between Acidulated Malt and lactic acid?
Acidulated Malt carries natural lactic acid on pale brewing malt and is measured as a percentage of the grain bill. Liquid lactic acid is concentrated and added directly to the brewing liquor or mash, allowing more precise adjustment.
Can Acidulated Malt be used with RO water?
Yes, but very low-alkalinity RO water may require only a small addition—or none at all—depending on the grain bill. Build the intended mineral profile first, calculate the expected mash pH and confirm it with a calibrated meter.
Can Acidulated Malt be used in dark beer?
Yes, although roasted and dark crystal malts already lower mash pH. Measure or calculate the expected pH carefully to avoid making the mash excessively acidic.
Does Acidulated Malt need to be mashed?
Yes. It should be crushed and mashed with the rest of the grain bill.
Does Acidulated Malt adjust sparge-water pH?
Not directly. It works within the mash. If sparge water requires acidification, a measured addition of phosphoric or lactic acid to the water is generally more suitable.
What can I substitute for Weyermann Acidulated Malt?
Gladfield Sour Grapes Malt can be used as a grain-based alternative. Food-grade lactic acid or phosphoric acid can also lower mash pH, but the required amount must be calculated for the acid concentration and brewing water.
Buy Weyermann Acidulated Malt online from Border Brewing Supplies. Available freshly packed and milled or unmilled for home brewers throughout Australia, with local collection from our Tweed Heads South home brew shop, conveniently located for customers from the Gold Coast, Brisbane, Northern Rivers and QLD–NSW border region.
