Lactic Acid Bacteria

Application of lactic acid bacteria

There are four major categories for the current uses and applications of LAB: food, cosmetic, pharmaceutical, and chemical applications.

In food industry

Recent years the interest increased in using LAB by using bacteriocin-like inhibitory substances (BLIS) because of their potential use as a natural antimicrobial agent to enhance the food safety of food products and increase the nutritional values of the food. Foods that fermented by LAB such as cheese, kimchi, fermented sausages, wine, yogurt and pickles have not only a greatly extended shelf life compared to the raw materials from which they are derived, but also enhance the aroma and flavor directly or indirectly by the fermenting organisms. There have many lactic acid fermentation products that have been used since long time ago such as Kimchi (korea), Yogurt (eastern Europe), Dahi (india n Nepal) and cheese (Europe n middle east).

Cheese

The basic steps of cheese production are acidification, coagulation, dehydration, and salting. While acid production is the major function of the starter bacteria. LAB is responsible for the fresh acidic flavor of unripened cheese and is important in coagulation of milk casein, which is accomplished by the combined action of the enzyme rennet. During the ripening process the LAB also producing volatile flavor compounds such as diacetyl and aldehydes by releasing proteolytic and lipolytic enzymes involved in cheese ripening and by natural antibiotic substances that suppress growth of pathogens and other spoilage microorganisms.

For Cheddar and Colby cheese production, starter cultures include strains of Lactococcus lactis ssp.cremoris and Lactocoocus lactis ssp lactis. While, blue cheese require both and the mold Penicillum roqueforti is also added as a secondary for the flavor and blue color.

Health benefits of LAB

LAB also known as probiotics because they can promote intestinal balance and strengthen the immune system.

Managing Lactose Intolerance

-LAB convert lactose into lactic acid, their ingestion may help lactose intolerant individuals tolerate more lactose than what they would have

Effective diarrhea relief

- preventing and shortening the duration of several types of diarrhea

- LAB compete with pathogens for nutrients and space in the intestines

- By-products of metabolism may have a direct effect against the pathogens. For example, in vitro work shows that L. casei, L. acidophilus