Is Lactic Acid Vegan? The Vegan's Guide to Lactic Acid

Lactic acid is a naturally occurring bacteria. Does that make it vegan?

Close up shot of woman holding a bottle of organic fresh milk in supermarket
Oscar Wong / Getty Images

Made from the bacterial fermentation of sugar, lactic acid appears as an additive in vegan foods ranging from sourdough bread to soy sauce. This bacteria gives food its signature sour taste and acts as a preservative. Most commercially produced lactic acid is cultivated on sugar beets, cane sugar, and corn starch, making it vegan-friendly. However, some vegans express concern that lactic acid can also be grown on lactose, a dairy sugar. 

Discover how this bacteria got its name, how it flavors your food, and how to make sure your next meal that contains lactic acid is cruelty-free.

Why Lactic Acid Is Usually Vegan 

Lactic acid is a naturally occurring bacteria produced during the fermentation of sugar. In the same way yeast ferments with sugar to become carbon dioxide, lactic acid bacteria (commonly known as LAB) ferments with sugar into lactic acid. Although many different bacteria can be used for food fermentation, industrial production generally opts for bacteria from the Lactobacillus, Lactococcus, and Bacillus orders. While lactic acid isn’t technically a plant, it is primarily cultivated on plant sugars and therefore meets the requirements of vegan food.

Many plant-based eaters assume that it is a dairy-based product because lactic acid contains the Latin prefix “lac-” (meaning milk). That assumption makes sense given that the Swedish chemist who discovered lactic acid isolated it from sour milk—hence its name. But the fact remains that most commercially available lactic acid contains no dairy and is naturally vegan. 

As a food additive, lactic acid is an odorless, clear to yellow-colored syrup. Manufacturers use it as a curing and pickling agent, a flavor enhancer, a pH regulator, and a preservative. Sauerkraut, pickles, salad dressings, desserts, jams, and more that contain lactic acid not only retain their structural integrity for extended periods of time but they also keep their distinctive taste.

When Is Lactic Acid Not Vegan?

Lactic acid can be cultivated on lactose, a dairy sugar. Since the manufacturing process essentially removes any animal-based molecules from the final lactic acid bacteria, dairy-cultured lactic acid is not identified on labels. For strict vegans, this may mean contacting manufacturers directly to inquire about the cultivation sources of the lactic acid in otherwise vegan products.

Additionally, fermented dairy products like kefir, cottage cheese, and yogurt, and cured meats can contain lactic acid. Since plant-based eaters avoid them already, they are of little concern.

Did You Know?

Lactic acid may play a role in our future food packaging. When the water molecule is removed from lactic acid bacteria, it becomes polymerized, transforming the syrup into a moldable bio-plastic. PLA (polylactic acid) plastics contain no fossil fuels and can be composted or recycled with similar bio-plastics.

Products to Avoid That Include Lactic Acid

Red wine
Lactic acid plays a role in wine fermentation. Image Source / Getty Images

Lactic acid appears in a variety of foods—some that are obviously not vegan, some that are less obvious. Assuming that lactic acid was plant-cultivated, these foods often contain other non-vegan ingredients.

Baked Goods  

Because of its excellent preservative qualities, lactic acid appears in a variety of breads and desserts that could contain non-vegan honey, eggs, and dairy. 

Dressings and Spreads

Watch out for non-vegan foods like dairy, eggs, and honey in products like marinades, jams, and salad dressings. While the lactic acid may be vegan, other ingredients might not be.

Wine 

Most wines are not vegan as they contain animal-derived isinglass and gelatin as part of the clarifying process. Lactic acid often plays a role in the initial stages of wine fermentation. 

Vegan-Friendly Products That Include Lactic Acid

Jar of Kimchi
A vegan favorite, kimchi contains lactic acid.

Lacaosa / Getty Images

Many naturally vegan foods contain lactic acid, giving these foods their signature sour taste and extending their shelf lives. 

Beer 

For the most part, beer is vegan-friendly, and it often contains lactic acid as a function of its flavor profile. Some beers, specifically British cask beers and some American porters, contain non-vegan isinglass—a fish-derivative used to remove impurities.

Sourdough Bread

A vegan favorite, sourdough bread can contain yeast and lactic acid, both of which contribute to its tart taste and long shelf life.

Pickled Fruits and Vegetables

The zing behind pickled fruit and veg? Lactic acid. Not only does it keep your kimchi crunchy by preserving the cabbage, but lactic acid also gives pickled veggies that extra bite in the back of your tongue.

Olives 

Lactic acid is the primary fermentation agent in jarred olives. It helps preserve their texture and enhances their already rich flavor. 

Soy Products

Many soy products are fermented with lactic acid, including miso, soy sauce, and tempeh.

Frequently Asked Questions
  • Is lactic acid vegan?

    In general, yes. The majority of commercially produced lactic acid was cultivated on plant sources, although it can be grown on the dairy sugar lactose.

  • Is lactic acid dairy-free?

    As a bacteria, lactic acid is by definition free of any animal products, but lactic acid can be grown on the non-vegan milk sugar lactose. Even so, by the time it reaches consumers, there is no trace of animal product in the lactic acid. Plus, the majority of lactic acid in premade foods was cultivated on plants.

  • Is lactic acid in olives vegan?

    Yes. The majority of commercially produced lactic acid was grown on vegetables, it’s safe to assume the lactic acid that ferments and preserves your olives is also vegan.