# Probiotics and Beneficial Microorganisms in Biopreservation of Plant-Based Foods and Beverages
## 2 The Need for Biopreservation  
Foodborne pathogens are biological agents that cause foodborne illnesses, leading to foodborne disease outbreaks. Foodborne illnesses occur when a pathogen is ingested and establishes itself in the host or when a toxicing pathogen establishes itself in a food product and produces a toxin, which is then ingested by the human host [7]. More than 200 foodborne diseases have been identified, and most severe cases occur in those patients who have compromised immune system function for example, very old and very young [8,9]. _Bacillus cereus_, _Campylobacter jejuni_, _Clostidium botulinum_, _Clostidium perfingens_, _Cronobacter sakazaki_, _Escherichia coli_, _Listeria monocytogenes_, _Salmonella_ spp., _Shigella_ spp., _Staphylococcus aureus_, _Vibrio_ spp., and _Yersinia enterocolitica_ are some of the most common foodborne pathogens which more commonly linked with foodborne diseases [7]. Suppression of foodborne pathogens in food products by probiotics has been reported in the literature. Similarly, pathogen suppression by probiotics in vivo in the human body has also been described [10]. The exact probiotic mechanism in pathogen suppression in food products during processing and storage seems to differ from that within the human body. For example, the production of short-chain fatty acids by probiotics lowers the product pH in fermented dairy foods and creates an unfavorable environment for certain pathogenic microorganisms. In addition, certain probiotics can produce bacteriocin when incorporated into food products. These are beneficial as they prevent the ingestion of higher numbers of pathogens with food products. When probiotic microbes are in the human body after ingestion, the mechanisms may be associated with the prevention of pathogenic microorganisms from attaching the intestinal epithelium, with a competitive advantage for nutrients and with the release of bacterios or other antimicrobial agents active against pathogenic microorganisms [10, 11, 12, 13]. Nonetheless, the synergistic nature of pathogen suppression by probiotics in food products and after ingestion within the human body should be further investigated in future research. Biopreservation is defined as the utilization of non-pathogenic microorganisms or their metabolites to increase the shelf life and enhance food safety by the destruction or inhibition of undesirable microorganisms present in food [14]. Fermentation is one of the most common forms of food biopreservation. Naturally present or externally added microorganisms are involved in the breakdown of complex food compounds along with producing alcohols, organic acids, and various industrial preparations. The fermentation results in the production of aroma and taste components, a process which improves the organoleptic properties of the food [15]. However, one of the main challenges when fortifying food products with probiotics is obtaining consumers' acceptance due to the development of off-flavors by certain probiotic strains. Due to this reason, alterations in organoleptic properties in some groups of raw materials or products are not recommended, for example, in products with higher fat content. Thus, for this sort of raw materials/product, strains that cause no or negligible alterations to the original flavor should be recommended for biopreservative purposes. This suggest that the selection of a strain as a biopreservation agent should be based on the nature of the raw material or product. The most widely used biopreservatives in industrial applications are lysozymes, bacteriophages, lactic acid bacteria and their bacteriocins. Lysozymes are natural enzymes present in bodily secretions, known for their antibiofilm characteristics. Bacteriophages are viruses that infect bacteria, and their antibacterial properties make them an efficient biopreservative. Bacteriocins are biologically active complex proteins or peptides that show antimicrobial action against closely-related bacterial species [16].