Insights into the current evidence on the effects of essential oils toward beneficial microorganisms in foods with a special emphasis to lactic acid bacteria – A review

Background The use of essential oils (EO) as natural antimicrobials to control spoilage and pathogenic microorganisms in foods has been research focus. However, few studies have investigated the impacts of EO on microorganisms acting as technological tools or capable of exerting beneficial properties on host health. Substances capable of impacting the physiological functions, metabolic capacities and growth/survival of microorganisms with technological or probiotic aptitudes could affect directly the development of desired characteristics in finished products. Scope and approach This review discusses the available literature concerning the effects of EO toward beneficial microorganisms in foods, including indigenous microorganisms and added cultures with technological or probiotic aptitudes, wiht a special empahsis to lactic acid bacteria. Available data have shown that EO could have variable effects on growth and metabolic activities of these microorganisms. Inhibitory or stimulatory effects of EO on technological and probiotic microorganisms could vary according to the type of EO and tested dose, examined microorganism and food formulation. Studies have chiefly focused on measurements of microbial growth in fermented dairy and meat products with EO. Information about the effects of EO on fermentation evolution and microbial physiological aptitudes in these foods are still scarce. Investigations need to advance to help the selection of EO and doses causing no or few adverse effects on these beneficial microorganisms in foods. Key findigs and conclusion Indded, a possible implication of the adjunction of EO to these products could be their effects on populations of indigenous or incorporated benefical microrganisms account for fermentation and development of desired quality characteristics, authenticity and functionalization of fermented foods.