How Much Lactic Acid to Add to The Mash?

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Your mash pH level is one of the keys to successful fermentation. The ideal range for most ales is 5.2-5.6, and lactic acid is often used to lower the pH of your mash. So, how much lactic acid to add to the mash to get the desired pH?

How Much Lactic Acid to Add to the Mash?

1.5ml to 2.0ml of 88% Lactic Acid is added to 1 gallon of mash to have a 5.2-5.4 pH target. This calculation is for a single-step infusion mash at 148 to 156°F, and it’s the right time to get the mash pH in the ideal range. Most brewers add the acid to the mash and recirculate it for 15-20 minutes. This allows the acid to be evenly distributed and to take effect.

A clear glass filled with cold foamy beer was placed on a brown wooden table outside

Before using this acid, ensure it is at room temperature. Also, be sure to take a pH reading of your wort before and after adding the acid to ensure you hit your target. This acid is available in different strengths, so make sure you know how much acid you have before calculating how much to add. The ideal strength is 88%, and anything lower will not be as effective in lowering the pH.

As always, taste your beer before you bottle or keg it. You can use a quality pH meter to test the final beer to ensure it is where you want it. If your acid is at a lower strength, you will need to add more of it to the mash to achieve the desired pH.

How Do You Make Sour Beer?

Beer souring has been gaining popularity in recent years. Brewers are experimenting with different techniques to create new and exciting sour beer styles. The most common method of souring beer is by using wild yeast or bacteria to ferment the beer. This can be done by adding fruit to the beer or brewing with barrels used to age sour drinks.

The other souring method is adding lactobacillus bacteria to the wort to sour it during brewing. This method is less common; however, it is gaining popularity as brewers learn more about lactobacillus and how to control it and other bacteria during the brewing process. 

Lactobacillus is a type of bacteria found in milk and other dairy products. It’s known for producing lactic acid, which is why it is often used for souring beer. Lactobacillus is added to the wort in a process called “souring.” Souring is a term used to describe the process of adding bacteria to wort or beer to create a sour flavor. Souring can be done before fermentation, during fermentation, or after fermentation.

What Are the Different Types of Soured Beers?

Most commercial brewers have developed ways to come up with different types of sour beer. However, many craft brewers are still experimenting with different techniques to create new and exciting sour beer styles. Some of these beer styles include:

  • Berliner Weisse: Also known as the Champagne of the North, this beer is light, tart, and refreshing. It is traditionally brewed with lactic acid bacteria and wheat to create its unique flavor.
  • Gose: This beer is tart and salty with a touch of coriander. It is a German-style beer dominated by saltiness, lemon sourness, and a touch of sweetness. Its sourness comes as a result of using Lactobacillus bacteria. It has an alcohol content of 4-5%
  • Lambic: This beer is a spontaneously fermented Belgian-style beer. It is tart, dry, and complex with a musty aroma. The beer has the ability to utilize wild yeast and bacteria from the surroundings to create a unique flavor. Lambic beer is often used in the production of fruit beer.
  • Flanders Red Ale: This beer is a Belgian-style ale that is reddish in color. It is tart, acidic, and complex with a sweet and malty finish. This beer gets its sourness from the aging process and Brettanomyces yeast. The beer is aged in oak barrels for up to two years to have its unique flavor.
  • Oud Bruin: This beer is a Belgian-style brown ale that is tart and complex. It has a sweet and malty finish with a hint of caramel. This beer is brewed with Lactobacillus bacteria to enhance its sour flavor. It has an alcohol content of 4-8%
A man pouring a foamy beer in clear glass and a bottle opener is placed on a brown wooden table

Frequently Asked Questions

How Do You Make Sour Beer Taste Better?

The best way to make sour beer taste good is by adding lactobacillus to the wort. This is a bacteria that is found in milk and other dairy products. It is known for producing lactic acid, which is why it is often used in sour alcoholic drinks.

Is Sour Beer Bad for You?

No, It is not bad for you. In fact, it has many health benefits, including improved digestion, immune system, and weight loss.


Adding lactic acid to achieve the desired pH level should be done with caution. Too much acid can sour the drink. The brewer should start with a small amount and taste the beer before adding more acid. The goal is to add enough acid to achieve the desired pH level.