BIOPRESERVATION By: Alyzza Loren D. Luansing BSED-TLE 311
BIOPRESERVATION • Biopreservation, defined as the extension of shelf life and enhanced safety of foods by the use of natural or controlled microbiota and/or antimicrobial compounds, is an innocuous and ecological approach to the problem of food preservation and has gained increasing attention in recent years. • It is biological preservation of foods referred to as extension of shelf life and the improvement of safety of products by mean of the endogenous microflora or using cultures as starters for protective, and/ or their metabolites. • It also referred to a combination of fermentation and preservation processes and entails the extension of shelf life and improving the safety of food. • Biopreservation refers to the use of antagonistic microorganisms or their metabolic products to inhibit or destroy undesired microorganisms in foods to enhance food safety and extend shelf life.
It also referred to a combination of fermentation and preservation processes and entails the extension of shelf life and improving the safety of food. One of the most common forms of food bio preservation is fermentation, a process based on the growth of microorganisms in foods, whether natural or added. These organisms mainly comprise lactic acid bacteria, which produce organic acids and other compounds that, in addition to antimicrobial properties, also confer unique flavor's and textures to food products. Traditionally, a great number of foods have been protected against spoiling by natural processes of fermentation.
Lactic acid bacteria have antagonistic properties which make them particularly useful as bio preservatives. When LABs compete for nutrients, their metabolitesoften include active antimicrobials such as lactic and acetic acid, hydrogen peroxide, and peptidebacteriocins. Some LABs produce the antimicrobial nisin which is a particularly effective preservative. A bacterium that is a suitable candidate for use as a bio preservative does not necessarily have to ferment the food. But if conditions are suitable for microbial growth, then a bio preservative bacterium will compete well for nutrients with the spoilage and pathogenic bacteria in the food. As a product of its metabolism, it should also produce acids and other antimicrobial agents, particularly bacteriocins.
Bacteriocins can be defined as protein containing macromolecules with a capacity to exert bactericidal action on susceptible bacteria. Bacteria used in bio-preservation should be harmless to humans, complete well with spoilage and pathogenic microorganisms for nutrients of food if conditions are conducive to microbial growth, and produces acids and other antimicrobial agents, particularly bacteriocins.
The main goal of bio-preservation is the enhancement of safety using bacteria with antimicrobial capabilities or their substances. Bio-preservation aims for the reduction of health risks without changing the organoleptic properties of the products.
In fish processing, biopreservation is achieved by adding antimicrobials or by increasing the acidity of the fish muscle. Most bacteria stop multiplying when the pH is less than 4.5. Traditionally, acidity has been increased by fermentation, marination or by directly adding acetic, citric or lactic acid to food products. Other preservatives include nitrites, sulphites, sorbates, benzoates and essential oils. These days LAB bacteriocins are used as an integral part of hurdle technology.Using them in combination with other preservative techniques can effectively control spoilage bacteria and other pathogens, and can inhibit the activities of a wide spectrum of organisms.