Investigation published in Journal of Food Protection

August 1^st, 1987

The susceptibility of Listeria monocytogenes to hydrogen peroxide in sterilized and raw milk was studied. In raw milk, L. monocytogenes was less susceptible to H2O2 than milk microflora. The ratio of L. monocytogenes to total milk micro-organisms (natural microflora plus added L. monocytogenes) increased when raw milk was stored at refrigeration temperature (4°C), due to a selective enrichment of Listeria present in milk. In sterilized milk, a concentration of 0.0495% H2O2 and 9 h were required to produce complete destruction of L. monocytogenes when this microorganism was in pure culture, although a reduction in listeria counts was observed at 1.5 h. When sterilized milk was simultaneously contaminated with L. monocytogenes, Staphylococcus aureus and Streptococcus faecalis, a decrease in L. monocytogenes count during the first 24 h was observed at 0.0495% H2O2. From this time L. monocytogenes recovered and multiplied reaching levels similar to the initial counts at the end of the experiment

Dominguez L., Fernandez-Garayzabal JF., Rodriguez-Ferri E., Vazquez-Boland JA., Gomez-Lucia E., Ambrosio C. and Suarez G.

Viability of Listeria monocytogenes in milk treated with hydrogen peroxide

	Departamento de Sanidad Animal. Facultad de Veterinaria. Universidad Complutense (UCM).
	Servicio de Zoonosis de Transmisión Alimentaria y Resistencia a Antimicrobianos (ZTA). Servicio de Identificación y Caracterización Microbiana (ICM). Centro de Vigilancia Sanitaria Veterinaria (VISAVET). Universidad Complutense (UCM).