Growth and survival of Listeria monocytogenesin two traditional foods from the United Arab Emirates

Abstract

The survival ofListeria monocytogenes in two foods of Arabic origin, namely labneh and houmos, was studied. Counts ofL. monocytogenes in excess of 10000 cfu g −1from labneh (pH 3.8) were reduced to zero within 72 h at 4 and 10°C, but increased survival was noted at pH 4.5, especially in unsalted labneh; at 30°C, no organisms could be detected 24 h after inoculation. From a starting count of 27000 cfu g −1, L. monocytogenes was able to survive on houmos throughout the anticipated shelf life (3 days); when houmos was stored at 4 and 10°C under olive oil, the numbers ofListeria declined slowly over 3 days. It was concluded that care should be taken to avoid the contamination of houmos withListeria during preparation in the kitchen.