from indigenous fermented foods and human gut ... - Thapar University

2.4.2 Application of bacteriocins in food
Chapter II Review of Literature
Most bacteriocin-producing LAB are indigenous food isolates and due to their great potential
in food preservation, bacteriocins has been subjected to extensive research during the last few
years. The studies show their great potential in biopreservation, for example in dairy
products, canned food and alcoholic beverages. Although numerous methods other than
bacteriocins are available for the preservation of food and beverages, an increasingly health
conscious public are looking for foods that have not undergone extensive processing and
contain no chemical preservatives. Bacteriocins are often promoted as potential
biopreservatives, but it is generally suggested that these antimicrobial peptides should not
primarily be used to prevent the growth of spoilage microorganisms. They rather should be
used in addition, to decrease the possibility of spoilage (Deegan et al., 2006). Bacteriocins
can be introduced into food to improve its safety in the following ways: i) in fermented food
where bacteriocins can be produced in situ by bacterial cultures which can replace either all
or part of a starter culture; (ii) purified or semi-purified bacteriocins can alternatively be
added directly as an additive; or (iii) an additive based on a fermentate of a bacteriocin-
producing strain (Cotter et al., 2005). Incorporating purified bacteriocins might not always be
attractive to the food and beverage industry, since in this form bacteriocins may have to be
labelled as an additive like other preservatives and regulatory approval might be necessary
(Deegan et al., 2006). Several important factors must be considered when screening for a
bacteriocin producing strain with potential in food application: the bacteriocin should have a
broad spectrum of inhibition and be highly active; it should also be heat-stable, have no
associated health risks and it should bring beneficial effects such as improved safety, quality
and flavour (Cotter et al., 2005). The physical and chemical properties of the food or
beverage can also influence the efficiency and stability of a certain bacteriocin and have to be
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