Preservative of Essential Oil Blends: Control of Clostridium perfringens Type a in Mortadella

Abstract The aim of this study was to evaluate the antimicrobial effect of the essential oils of cinnamon, cardamom, clove, oregano, and thyme and their synergism on vegetative cells and endospores of Clostridium perfringens type A inoculated in meat sausage (mortadella), as well as the influence of blends on the color, and lipid oxidation through the determination of thiobarbituric acid reactive substances (TBARS index). The anticlostridial action of the oil blends was established. The two added oil blends (Treat. 1: oregano, clove, and thyme; Treat. 2: oregano, clove, and cinnamon) in combination with reduced nitrite content (75 ppm) promoted a lower growth of C. perfringens in mortadella stored at 15 °C for 21 days in comparison to treatments containing only 75 ppm of nitrite. The essential oil blends showed antioxidant action and did not alter food color, thus possessing potential application as a preservative for the meat products industry.

Óleos essenciais e nanoemulsões como alternativas no controle de Clostridium sporogenes em mortadela / Essential oils and nanoemulsions as alternatives in the control of Clostridium sporogenes in mortadela

Avaliou-se a ação antimicrobiana da combinação dos óleos essenciais de canela, pimenta chinesa, limão Taiti e cardamomo e de suas nanoemulsões no controle de Clostridium sporogenes e sua influência sobre a oxidação lipídica em mortadela. A Concentração Mínima Bactericida (CMB) de cada óleo foi determinada pelo método de macrodiluição. As CMB encontradas foram: 0,10% óleo essencial de pimenta chinesa e canela e 1,00% óleo essencial de cardamomo e limão Taiti. A nanoemulsão elaborada apresentou redução significativa no número de células vegetativas de C. sporogenes na mortadela, além de ser o tratamento mais eficiente no controle da oxidação lipídica. Os resultados obtidos comprovam a ação antimicrobiana dos óleos testados, sugerindo sua possível utilização como conservantes naturais em produtos alimentícios.

Synthesis and in vitro evaluation of peracetyl and deacetyl glycosides of eugenol, isoeugenol and dihydroeugenol acting against food-contaminating bacteria.

Essential oils, as well as their separate components, have shown promise as alternatives to synthetic preservatives. Therefore, it would be interesting to optimize the effect of these compounds and to evaluate their applicability as additives in food. To this end, six peracetyl and deacetyl glycosides were synthesized from eugenol, isoeugenol and dihydroeugenol. All of the glycosides were characterized by IR and NMR. The synthesized compounds and their aglycones were evaluated to determine their minimal bactericidal concentrations (MBC) against the spoilage food bacteria Escherichia coli, Listeria monocytogenes, Staphylococcus aureus and Salmonella enteritidis. All deacetyl glycosides were about twice as active as aglycones, and the peracetyl glycosides were, in most cases, equipotent with aglycones. The deacetyl glycoside of dihydroeugenol proved to be the most active compound against the bacteria tested, with a 0.37% MBC v/v for E. coli and 0.18% v/v for the other bacteria.