Revista de Salud Animal
versão ISSN 0253-570X
ARMENTEROS, Mabelin et al. RISK ANALYSIS OF THE EXACERBATION OF FOODBORNE PATHOGENS IN RAW MILK ACTIVATED WITH THE LACTOPEROXIDASE SYSTEM. Rev Salud Anim. [online]. 2007, vol.29, n.3, pp. 176-181. ISSN 0253-570X.
One of the most studied systems in the last 20 years. The lactoperoxidase-thiocyanate-hydrogen peroxide system (LP System) is due to its potential possibilities to avoid raw milk deterioration against undesirable microorganisms. There are experimental and practical evidences demonstrating that the use of this method is innocuous. That is why, the Committee of Experts for Food Additives (JECFA) has pointed out that it is acceptable from the toxicological point of view. However, CODEX guidelines have identified the need of having greater information about the risk of exacerbation of pathogen bacteria present in milk because of the inhibition of the natural flora present in raw milk. The objective of the present study consisted on evaluating the effect of the LPs activation on the exacerbation of several foodborne pathogens: Salmonella spp., Staphylococcus coagulase-positive, Escherichia coli 0157:H7, Listeria monocytogenes and Bacillus cereus in raw milk. The experiment was carried out at the Venizie Institute in Italy. The raw milk, used in the three replicas for each microorganism studied, had good quality and it was free of microbial growth inhibitor substances. Later, foodborne pathogens were inoculated with charges 102-104 CFU/mL. The analyses used were those techniques established for the detection and/or enumeration of these pathogens. As a carrier of the LPs active principles, a product named STABILAK was used, bringing an equivalent quantity of 9 mg/L of sodium thiocyanate and 34 mg/L of sodium percarbonate. Test times per each replica in milk treated with the product (activated milk) and control milk were 0, 4, 8 and 12 hours. The LPs effects observed at 12 hours, according to the total bacterial count, showed a highly significant reduction (P<0.01) of the counting in activated milk with respect to the control; for Staphylococcus coagulase-positive, Bacillus cereus and Listeria monocytogenes, though there were no significant differences, but the control sample showed a higher growth than the activated milk. In the cases of Salmonella spp. and Escherichia coli O 157:H7, there was a similar trend between both samples without significant differences. The general behavior indicates that there was no exacerbation of the pathogens studied. Thus there is not any microbiological risk for the consumer, associated to the use of this preservation method.
Palavras-chave : LP system; foodborne pathogens; risk analysis; milk.