Antimicrobial effectiveness of spices: an approach for use in food conservation systems

ABSTRACT There has been constant an increasing the search alternative and efficient compounds for food conservation, aiminga partial or total replacement of antimicrobial chemical additives. Spices offer a promising alternative for foodsafety. Inhibitory activity of spices and derivatives on the growth of bacteria, yeasts, fungi and microbial toxinssynthesis has been well reported, so they could be used in food conservation as main or as adjuvant antimicrobialcompounds in order to assure the production of microbiologically stable foods.Key words: Spices, essential oil, extracts, chemical compounds, antibacterial activity, antifungal activity INTRODUCTION Food conservation has been characterized fornutritious and microbiologically stable foods and ithas been archived by controlling the growth ofspoiling and pathogenic food-relatedmicroorganisms. Microbial control in foods couldbe assured by suppressing one or more essentialfactors for microbial survival (Horace, 1982). Itcould be possible by adding suitable substances(weak organic acids, hydrogen peroxide, chelators,organic biomolecules) and applying physical(temperature, packaging) and/or chemicalprocedures (pH, oxide-reduction potential, osmoticpressure) (Ray, 1996; Brull and Coote, 1999).These procedures could kill or make unviablesome microorganisms.There has been increasing concern of theconsumers about foods free or with lower level ofchemical preservatives because these could betoxic for humans (Bedin et al., 1999).Concomitantly, consumers have also demandedfor foods with long shelf-life and absence of riskof causing foodborne diseases. This perspectivehas put pressure on the food industry forprogressive removal of chemical preservatives andadoption of natural alternatives to obtain its goalsconcerning microbial safety. This resulted inincreasing search for new technologies for use infood conservation systems, wich include: modifiedatmosphere packaging, combined effect ofunderlethal procedures, alternative antimicrobialcompounds (ecstatic or cidal effect), combinationof conventional (used in low levels) andalternatives antimicrobials (Brull and Coote,1999).Uncontrolled use of chemical antimicrobialpreservatives has been inducing factor forappearance of microbial strains more and moreresistant to classic antimicrobial agents. Difficult