Lactic acid bacteria products

Brevis 3 L. Brevis 3 L.

However the high number of samples analysed daily require new enumeration methods with improved efficiency convenience and ease-of-use.

Lactic acid bacteria products. Lactic acid bacteria produce a variety of metabolic products that are capable of interfering with the growth of other microbes. These bacterial end products have been applied to food systems to prevent the growth of certain undesirable bacteria. The following review will discuss the successful application of several of the metabolic products produced by lactic acid bacteria in food systems.

The lactic acid bacteria are a group of Gram-positive bacteria non-respiring non-spore-forming cocci or rods which produce lactic acid as the major end product of the fermentation of carbohydrates. Olives and Olive Oil in Health and Disease Prevention 2010. Products of lactic acid fermentation are very useful in our daily life as contribute nutritive value to our foods.

These products produced from lactic acid fermentation contain various lactic acid bacteria that breakdown sugars to produce Lactic Acids. Lactic acid is an important platform chemical for producing polylactic acid PLA and other value-added products. It is naturally produced by a wide spectrum of microbes including bacteria yeast and filamentous fungi.

In general bacteria ferment C5 and C6 sugars to lactic acid by either homo- or hetero-fermentative mode. LAB are nonsporeforming Gram-positive catalase-negative without cytochromes nonaerobic or aerotolerant fastidious acid tolerant and strictly fermentative bacteria with lactic acid as the major end-product during sugar fermentation. For centuries lactic acid bacteria have been used to produce fermented food products including pickles sauerkraut sausage yogurt cheese buttermilk soy sauce and more.

Some examples include Streptococcus thermophilus along with Lactobacillus bulgaricus that are used in the production of yogurt. When the growth of aerobic spoilage bacteria is inhibited lactic acid bacteria may become the dominant component of the microbial flora of meats. This occurs with cured meats and with meats packaged in films of low gas permeability.

The presence of a flora of psychrotrophic lactic acid bacteria on vacuum-packaged fresh chilled meats. Lactic acid bacteria populations in the vacuumpacked meat products analysed. Species composition and evolution.

Table 1 shows the population species composition for the different meat products analysed. Cooked ham that was gas spoiled was dominated by Leuc. Divergens was also present.

The application of antimicrobial-producing lactic acid bacteria LAB or food-grade ferments in the manufacture of dairy products which can be incorporated into fermented or nonfermented dairy products implies a processing additional advantage to improve the safety and increase the quality of dairy products providing an additional hurdle to reduce the likelihood of food-borne diseases Table 1. Phase contrast microscopy of some important lactic acid bacteria. 1 Bifidobacterium sp 2 L.

Brevis 3 L. Bulgaricus and Streptococcus thermophilus in yoghurt. In fermented meat products mainly bacteria like lactic acid bacteria LAB and Micrococcaceae but also yeasts and molds 1 2 influence the technological properties of the product for instance their quality and safety 3.

As so-called starter cultures those organisms initiate the fermentation process. Lactic acid bacteria perform this essential function in preserving and producing a wide range of foods. Fermented fresh vegetables such as cabbage sauerkraut Korean kimchi.

Fermented cereal yogurt Nigerian ogi Kenyan uji. Sourdough bread and bread-like products made without wheat or rye flours Indian idli Philippine. Lactic acid bacteria of meat and meat products.

When the growth of aerobic spoilage bacteria is inhibited lactic acid bacteria may become the dominant component of the microbial flora of meats. This occurs with cured meats and with meats packaged in films of low gas permeability. As the bacteria culture grows it converts lactose into lactic acid and other organic acids reducing the pH of milk Beresford et al 2001Høier et al 2010Bintsis 2018.

Lactic acid bacteria produce lactic acid as their main product. They are widespread in naturein soil vegetables meat milk and the human body. Many are used in fermented dairy products.

Thermophilus and Lactobacillus bulgaricus L. The general description of the bacteria included in the group is gram-positive nonsporing nonrespiring cocci or rods which produce lactic acid as the major end product during the fermentation of carbohydrates. 1 The common agreement is that there is a core group consisting of four genera.

Lactobacillus Leuconostoc Pediococcus and Streptococcus. Dextrose glucose is the most commonly used sugar for bacterial growth while lactose the principal sugar in dairy product is hydrolyzed relatively slowly and is one of the least utilized forms of sugars by lactobacilli strains Srinivas et al 1990. Most LAB require a wide range of growth factors.

The lactic acid produced by the bacterium lowers the pH of the product and preserves it from the growth by unwanted bacteria and molds while other metabolic products and enzymes produced by Lactococcus lactis contribute to the more subtle aromas and flavors that distinguish different cheeses. Lactic acid bacteria in food products are time consuming involving direct plating on solid selective media prepared by pour or spread plate technique. However the high number of samples analysed daily require new enumeration methods with improved efficiency convenience and ease-of-use.