Effects of environmental conditions and substrate on growth and ochratoxin A production by "Penicillium verrucosum" and "Penicillium nordicum": Relative risk assessment of OTA in dry-cured meat products.

Abstract

En este trabajo se estudió la influencia de la actividad del agua, la temperatura y la composición del sustrato sobre el crecimiento fúngico y la producción de OTA por Penicillium nordicum y Penicillium verrucosum aislados de productos cárnicos curado-madurados. Además, se evaluó el riesgo relativo de la presencia de OTA en productos cárnicos curado-madurados utilizando el software Risk Ranger. El crecimiento de los mohos se observó en el rango habitual del procesado de estos alimentos (0,99 a 0,90 de actividad de agua y 15 a 25 °C). P. nordicum y P. verrucosum pudieron producir OTA en todos los sustratos en estos rangos de actividad de agua y temperatura. La producción de OTA por P. verrucosum estuvo influenciada principalmente por la temperatura y la composición del medio. Sin embargo, P. nordicum se ve afectado principalmente por el sustrato o la temperatura dependiendo de la cepa estudiada. Ambas especies producen una gran cantidad de OTA en el jamón curado y en el salchichón en condiciones ambientales que suelen encontrarse durante la maduración de estos productos. El software Risk Ranger revela que el riesgo relativo de OTA en productos cárnicos curados-madurados es del 75%. Por lo tanto, se deben establecer medidas de control durante el procesamiento de productos cárnicos curados-madurados para prevenir el riesgo de OTA.

Ecological conditions during ripening of dry-cured meat products favour the growth of an uncontrolled mould population that could suppose a risk of ochratoxin A (OTA) production. In this work the influence of water activity (aw), temperature and substrate composition on fungal growth and OTA production by Penicillium nordicum and Penicillium verrucosum isolated from dry-cured meat products have been studied. In addition, the relative risk of OTA presence on dry-cured meat products has been evaluated using the Risk Ranger software. Fungal growth was observed in the range of 0.99–0.90 aw and 15–25 °C being mainly temperature-dependent. P. nordicum and P. verrucosum were able to produce OTA in every substrate in these ranges of aw and temperature. The production of OTA by P. verrucosum was mainly influenced by temperature and media composition. However, P. nordicum it is affected mainly by substrate or temperature depending on the strain studied. Both species produce a large amount of OTA on dry-cured ham and on dry-cured fermented sausage “salchichón” in environmental conditions usually found throughout the ripening of these products. The Risk Ranger software reveals that the relative risk of OTA on dry-cured meat products is 75%. Thus, control measures during dry-cured meat products processing to prevent OTA risk should be established.