What are Lactic Acid Bacteria (LAB)?

Lac Lactis Photo

“Lactic acid bacteria are among the most important groups of microorganisms used in food fermentation. They contribute to the taste and texture of fermented products and inhibit food spoilage bacteria by producing growth-inhibiting substances and large amounts of lactic acid. As agents of fermentation LAB are involved in making yogurt, cheese, cultured butter, sour cream, sausage, cucumber pickles, olives and sauerkraut, but some species may spoil beer, wine and processed meats.” Textbook of Bacteriology

Talking about Lactic Acid Bacteria (LAB) is as exciting to us as what the retooling of the Hubble telescope must be to those intrigued by the discoveries of new space frontiers! It’s new frontiers, amazing science, and the quest for life all rolled up in one and we don’t even have to leave Earth!

“The proliferation of lactobacilli in fermented vegetables enhances their digestibility and increases vitamin levels. These beneficial organisms produce numerous helpful enzymes as well as antibiotic and anticarcinogenic substances. Their main by-product, lactic acid, not only keeps vegetables and fruits in a state of perfect preservation but also promotes the growth of healthy flora throughout the intestine.” – Sally Fallon, Nourishing Traditions, pg 89

The lactobacilli described by Sally Fallon, are lactic-acid bacteria (LAB) – extremely important beneficial bacteria, essential to life. A representative of “lactobacilli” has become a household name over the past few decades – lactobacillus acidophilus – heavily-marketed by factory-produced yogurts. But there is so much more to LAB than just this one, albeit amazing, lactobacillus which factory-processes have taken out-of-context, separated from the other microbes without which, it would not exist.

Pasteur first discovered fermentation and created the field of microbiology. Nearly two centuries later, microbiology is still a brand-new frontier, but LAB discoveries – their life-restoring and healing properties which have been legendary going back to times of antiquity – are only now being confirmed with multi-million dollar microscopes, and even then, just a tiny fraction has been discovered, and barely explained.

With each discovery, lactic-acid bacteria taxonomy is frequently changing, bearing witness to the unraveling of LAB by modern microbiology, orthomolecular medicine, biology, food science and biochemistry!

“Application of molecular genetic techniques to determine the relatedness of food-associated lactic acid bacteria has resulted in significant changes in their taxonomic classification.”

“During the 1980s the genus Streptococcus was separated into the three genera Enterococcus, Lactococcus and Streptococcus. The lactic acid bacteria associated with foods now include species of the genera Carnobacterium, Enterococcus, Lactobacillus, Lactococcus, Leuconostoc, Oenococcus, Pediococcus, Streptococcus, Tetragenococcus, Vagococcus and Weissella”.

The genus Lactobacillus remains heterogeneous with over 60 species (ymol% G+C content ranging from 33 to 55), of which about one-third are strictly heterofermentative. However, many changes have been made and reorganization of the genus along lines that do not follow previous morphological or phenotypic differentiation from Leuconostoc and Pediococcus is being studied”. Pub med

LAB are part of a complex structure of microorganisms that recycle, grow and maintain everything from soil, insects, plants of every taxonomy classification, as well as every mammal – all dependent upon lactic acid bacteria for ongoing health.

Without LAB, there would be no lacto-fermentation” of foods, one of the oldest methods of natural-food preservation. No lovely sourdough breads, old-fashioned dill pickles, sauerkraut soy sauce, wine, beer, cheese, kefir, yogurt, coffee, tea, chocolate, kimchi, soy sauce, miso…an endless array of healthy foods that have played a vital role in every civilization since the beginning of time.

Lactic acid bacteria (LAB) are numerous, and each have a unique role in the amazing conversion of raw materials into lacto-fermented foods. The way they work together, pairing up with beneficial yeasts, as well as other micro-organisms, is similar to a square dance where they team up, changing partners – the dance always continuing but with new partners! Members of the L. klebsiella family, for example, are the first ones to take a step in the conversion of raw cabbage into sauerkraut. As the acidity of the brine changes, they bow out allowing the L. leuconostoc LAB to take a spin.

In addition to L. acidophilus, other lactic-producing bacteria involved in food fermentation include:

  • L. bulgaricus,
  • L. plantarum,
  • L. caret,
  • L. pentoaceticus,
  • L brevis and
  • L. thermophilus

Lactic acid bacteria are primarily located on the surface, or skin of fruits and vegetables.

Resist the urge to sanitize your food as you will kill important lactic acid bacteria. That is why it is always important to know where your food comes from – buy from local farms that use chemical-free, or organic methods. The same lactic-acid that thrive in a health fermented-food, thrive in the soil that grew the food! Buy from farmers who know how to nurture and feed the soil.

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Kenneth Todar’s Online Textbook of Bacteriology – Just a REALLY well done site which superb information. Combine the information at this website with making your own fermented food, and you have a great teaching took for your children!

Normal Skin Microflora

Lactobacillus & Natural Gardening

Microbiology for Teachers – and for those who love lacto-fermentation!

The Importance of Resistant Starch in the Diet and Colon Health

Introduction to Human Nutrition=

Short-Chain Fatty Acids and Human Colonic Function: Roles of Resistant Starch and Non-starch Polysaccharides

Internal colonic fermentation