Luciana Teixeira de Siqueira Rodrigues’s research while affiliated with Universidade Federal de Lavras (UFLA) and other places

The antimicrobial activity of essential oils on C lostridium perfringens type A and the influence of such oils on mortadella quality were assessed. The anticlostridial effects of several essential oils and their combinations were identified and some essential oils and their combinations were selected for further study in mortadellas supplemented with 75 ppm sodium nitrite and inoculated with C . perfringens . The growth of C . perfringens in mortadella was not inhibited by nitrite (control treatments of 75 and 150 ppm), but the essential oils presented a significant inhibitory effect. The essential oil of Origanum vulgare presented the highest anticlostridial activity. Moreover, higher concentrations of residual nitrite were found in mortadellas containing essential oils than in controls. Practical Applications C lostridium perfringens is an anaerobic bacteria, gram‐positive and with the ability to form spores that are highly resistant to environmental conditions and causes two important human illnesses: a relatively mild, classic type A diarrhea and the more serious type C human necrotic enteritis. Approximately 75% of cases of illness due to C . perfringens are attributed to meat, meat products and poultry. Nitrite and nitrate salts are added to cooked meat products to control the growth of sporulated bacteria, however, such salts can react with amines to form N ‐nitrous compounds, particularly nitrosamines, which are mutagenic, neurotoxic, nephrotoxic and carcinogenic. The natural compounds with antimicrobial activity can be used to reduce them. As high concentration of essential oils may negatively affect the flavor of foods, several combinations of essential oils should be minimized to the concentration required. The growth of C . perfringens in mortadella was not inhibited by nitrite, but the essential oils presented a significant anticlostridial activity shown to be possible to use.