Title
Quantitative risk assessment of Listeria monocytogenes in traditional Minas cheeses: The cases of artisanal semi-hard and fresh soft cheeses
Date Issued
01 October 2018
Access level
open access
Resource Type
journal article
Author(s)
Campagnollo F.
Pilão Cadavez V.
Sant'Ana A.
Schaffner D.
School of Agriculture
Abstract
This study estimated the risk of listeriosis from Brazilian cheese consumption using quantitative microbial risk assessment (QMRA). Risks associated to consumption of two cheese types were assessed: artisanal ripened semi-hard cheese (produced with raw milk) and refrigerated fresh soft cheese (produced with pasteurized milk). The semi-hard cheese model predicted Listeria monocytogenes growth or decline during ripening, while the soft cheese model predicted pathogen growth during refrigerated storage. Semi-hard cheese modeling scenarios considered L. monocytogenes starting concentration from −2.4 to 6 log CFU/mL in raw milk and three ripening times (4, 22 and 60 days). Soft cheese modeling scenarios considered L. monocytogenes starting concentration from −2.4 to 4 log CFU/mL in milk. The inclusion of anti-listerial lactic acid bacteria (LAB) in cheeses was also examined. Risk of listeriosis due to consumption of soft cheese was 6000 and 190 times greater than that of semi-hard cheese, for general and vulnerable populations, respectively. Aging semi-hard cheese reduced risk, and risk was influenced by L. monocytogenes starting concentration. Aging cheese with inhibitory LAB for 22 days reduced risk over 4 million-fold when L. monocytogenes was assumed to be 6 log CFU/mL in raw milk. The inclusion of inhibitory LAB also reduced risk of listeriosis due to soft cheese consumption, but not as much as for semi-hard cheese. QMRA results predicted that consumption of contaminated cheeses can carry a high risk of listeriosis, especially for vulnerable populations. Scenario analyses indicated that aging of semi-hard cheese and inclusion of antimicrobial LAB mix in semi-hard and soft cheeses are effective risk mitigation measures.
Start page
370
End page
379
Volume
92
OCDE Knowledge area
Alimentos y bebidas Epidemiología
Scopus EID
2-s2.0-85048499856
Source
Food Control
ISSN of the container
09567135
Sponsor(s)
The authors thank to Fundação de Amparo à Pesquisa do Estado de São Paulo for the financial support (Grants 2014/14891-7 and 2016/09346-5 ) and to Conselho Nacional de Desenvolvimento Científico e Tecnológico (Grant # 302763/2014-7 and # 305804/2017-0 ), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (Grant # 33003017027P1 ). Dr. Gonzales-Barron wishes to acknowledge the financial support provided by the Portuguese Foundation for Science and Technology (FCT) through the award of a five-year Investigator Fellowship (IF) in the mode of Development Grants ( IF/00570 ).
Sources of information: Directorio de Producción Científica Scopus