Biopreservation

When LABs compete for nutrients, their metabolites often include active antimicrobials such as lactic and acetic acid, hydrogen peroxide, and peptide bacteriocins.

[6]In addition to lactic acid bacteria, yeasts also have been reported to have a biopreservation effect due to their antagonistic activities relying on the competition for nutrients, production and tolerance of high concentrations of ethanol, as well as the synthesis of a large class of antimicrobial compounds exhibiting large spectrum of activity against food spoilage microorganisms, but also against plant, animal and human pathogen.

[15] Bacteriophages have recently received a generally recognized as safe status based on their lack of toxicity and other detrimental effects to human health for application in meat products in the USA.

[16] Phage preparations specific for L. monocytogenes, E. coli O157:H7, and S. enterica serotypes have been commercialized and approved for application in foods or as part of surface decontamination protocols.

[17][18][19] The use of native or artificially-introduced microbial population to improve animal health and productivity, and/or to reduce pathogenic organisms, has been termed a probiotic or competitive enhancement approach.

Generally speaking, competitive enhancement strategies offer a natural 'green' method to reduce pathogens in the gut of food animals.

[18] Fishery products are a source of wide variety of valuable nutrients such as proteins, vitamins, minerals, omega-3 fatty acids, taurine, etc.

[21] These milder treatments are usually not sufficient to destroy microorganisms, and in some cases psychrotolerant pathogenic and spoilage bacteria can develop during the extended shelf-life of LPFP.

[21] Among the microbiota identified in fresh or processed seafood, LAB remains the category that offers the highest potential for direct application as a bioprotective culture or for bacteriocin production.

[26] SalmoFresh is prepared with a cocktail of naturally occurring lytic bacteriophages that selectively and specifically kill Salmonella, including strains belonging to the most common/highly pathogenic serotypes Typhimurium, Enteritidis, Heidelberg, Newport, Hadar, Kentucky and Thompson.

Another commercial application has been developed, Listex_ P100 by Micreos in the Netherlands and was granted generally recognized as safe (GRAS) status by the FDA and USDA for use in all food products.

[16] Biopreservation judiciously exploits the antimicrobial potential of naturally occurring microorganisms in food and/or their metabolites with a long history of safe use.

The long and traditional role of lactic acid bacteria on food and feed fermentations is the main factor related to the use of bacteriocins in biopreservation.

Their antimicrobial spectrum of inhibition, bactericidal mode of action, relative tolerance to processing conditions (pH, NaCl, heat treatments) and the lack of toxicity towards eukaryotic cells enforces their role as biopreservatives in food.

The small rods shown here are lactic acid bacteria which convert lactose and other sugars to lactic acid . The products of their metabolism can have benign preservative effects.
3D stick model of nisin , a particularly effective preservative produced by some lactic acid bacteria.
[ 7 ] [ 8 ] [ 9 ] [ 10 ] This figure illustrates the pathway of food preservation followed by lactic acid bacteria involving nisin , as well as the pathway of food preservation followed by salt. Additionally, the hurdle effect of food preservation, such as by adding lactic acid bacteria and salt to a food product, is illustrated and described. [ 11 ] [ 12 ] [ 13 ] This figure illustrates the pathway of food preservation followed by lactic acid bacteria involving nisin , as well as the pathway of food preservation followed by salt. Additionally, the hurdle effect of food preservation, such as by adding lactic acid bacteria and salt to a food product, is illustrated and described.