Lactic Fermentation Process

The two most common methods of fermentation are alcoholic and lactic acid fermentation. The most well-known type might be alcoholic fermentation used in many foods and beverages, beer, wine, teas, sausages, breads, and more, although lactic acid fermentation is considered the oldest method. Lactic fermentation has been used for centuries in many foods and beverages such as yogurts and cheeses, pickled foods, sauerkraut, and more.

Lactic Fermentation Critical for Food Preservation

Lactic acid fermentation is generally inexpensive, requiring little to no heat, and plays an essential role in the preservation of wholesome foods. This makes lactic fermentation extremely important in feeding the world’s population on every continent.

According to an article posted by the National Library of Medicine, lactic acid fermentation combined with salting is one of the most practical methods of preserving food, particularly where frozen and canned foods are unavailable to hundreds of millions of hungry people living in economically deprived areas.

How Does Lactic Acid Fermentation Work?

Lactic fermentation is a metabolic process that converts glucose or other sugars into cellular energy, in an anaerobic fermentation reaction. Lactobacillus is the most common and important genus of lactic acid fermentation although other bacteria are sometimes used. Lactobacillus is considered the “good” bacteria and is found in the human gut, in the digestive and urinary tract, and can help the body absorb nutrients, break down food, and fight off disease-causing organisms.

Lactics in Beer

Lactobacillus metabolizes sugar similar to brewers’ yeasts, although unlike yeast it produces lactic acid instead of producing alcohol. This is desirable when making and preserving foods, although lactic acidity can be an off-putting flavor in many types of beer and will often make the beer look hazy. Some brewers might fear lactobacillus, although other types of beers include lactic fermentation as part of the beer’s characteristic flavor.

Lactic fermentation will add a sour taste and is common in many types of German, Belgian, and American sour beers. Malt typically includes a large population of lactobacillus. Some German beers include a small amount of malt to sour unhopped wort, which can then be used as mash or kettle wort in line with Reinheitsgebot, the beer Purity Law dating back centuries and still in the modern German Tax Law.

The amount of acids, particularly lactic and acetic, is what determines the sourness in particular beers. Some beers may be overpoweringly sour while others may have only a hint of tartness. Each style of beer is different and the level of sourness can vary even within the same beer style. Lactic fermentation is not an exact science and could create varying levels of sourness in different batches.

Home Brewing Fermenting Solutions

There are many instances where you may want to homebrew a sour beer, something like a red sour ale with some cherries or countless other tasty versions. Many innovative brewers are using acid successfully to tweak the flavor of their homebrews as many fruits have naturally enhanced flavors due to the presence of sugar or acid.

Fruits that are enhanced by sugar typically do not work well when brewing beer because the sugar is fermented out and the fruit flavor is lost. Fruits enhanced by acid tend to stay in the beer and enhance the fruit flavor due to the higher acidity. Many craft breweries actually use aseptic fruit juice, concentrate, or purée since they are close to fresh and manageable. Using whole fruit is an option but requires some processing.

Lactic fermentation has been around for centuries, a tried-and-true form of fermentation for making foods in many beverages including malt, wort, and beer.

RainMakers Supply is your one-stop to get answers for all your home brewing and winemaking questions. We are a leading homebrew supply store serving the Chicago area with quality brewing supplies, equipment, and ingredients including fermentation solutions. Contact us to learn more and check out our many home beer brewing supplies and accessories.