Interactions between bacteria are important in a natural ecosystem such as meat.
In addition to competition for nutrients, the production of antibacterial substances
such as hydrogen peroxide, lactic acid and bacteriocins is likely to select the
growing bacteria. Several lactic acid bacteria produce such metabolic products
(Holzapfel et al., 1995). It has been proposed that specific bacteria may be used as
a protective culture, delaying spoilage caused by other bacteria. Characteristics of
such bacteria would be: growth and production of antagonistic compounds during
prevailing storage collditions, and no off-odour production.