Food safety hazards associated with consumption of raw milk.

Department of Animal Science, The University of Tennessee, Knoxville, Tennessee 37996, USA.
Foodborne Pathogens and Disease (Impact Factor: 2.09). 10/2009; 6(7):793-806. DOI: 10.1089/fpd.2009.0302
Source: PubMed

ABSTRACT An increasing number of people are consuming raw unpasteurized milk. Enhanced nutritional qualities, taste, and health benefits have all been advocated as reasons for increased interest in raw milk consumption. However, science-based data to substantiate these claims are limited. People continue to consume raw milk even though numerous epidemiological studies have shown clearly that raw milk can be contaminated by a variety of pathogens, some of which are associated with human illness and disease. Several documented milkborne disease outbreaks occurred from 2000-2008 and were traced back to consumption of raw unpasteurized milk. Numerous people were found to have infections, some were hospitalized, and a few died. In the majority of these outbreaks, the organism associated with the milkborne outbreak was isolated from the implicated product(s) or from subsequent products made at the suspected dairy or source. In contrast, fewer milkborne disease outbreaks were associated with consumption of pasteurized milk during this same time period. Twenty nine states allow the sale of raw milk by some means. Direct purchase, cow-share or leasing programs, and the sale of raw milk as pet food have been used as means for consumers to obtain raw milk. Where raw milk is offered for sale, strategies to reduce risks associated with raw milk and products made from raw milk are needed. Developing uniform regulations including microbial standards for raw milk to be sold for human consumption, labeling of raw milk, improving sanitation during milking, and enhancing and targeting educational efforts are potential approaches to this issue. Development of pre- and postharvest control measures to effectively reduce contamination is critical to the control of pathogens in raw milk. One sure way to prevent raw milk-associated foodborne illness is for consumers to refrain from drinking raw milk and from consuming dairy products manufactured using raw milk.

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Available from: Kathryn J Boor, Jul 17, 2015
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    • "Staphylococcus aureus persistently colonizes the anterior nares of 20 to 30% of the human population (van Belkum et al., 2009), causes a multitude of infections in humans and livestock, and can be isolated from a wide range of food items (Baumgartner et al., 2014). The organism also represents a common cause of bovine mastitis and can be detected in bulk tank milk at prevalence rates of 27 to 42% (Oliver et al., 2009). On October 1, 2014, children and staff members at a Swiss boarding school consumed Tomme, a soft cheese produced from raw milk. "
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    ABSTRACT: On October 1, 2014, children and staff members at a Swiss boarding school consumed Tomme, a soft cheese produced from raw cow milk. Within the following 7 h, all 14 persons who ingested the cheese fell ill, including 10 children and 4 staff members. Symptoms included abdominal pain and violent vomiting, followed by severe diarrhea and fever. We aim to present this food poisoning outbreak and characterize the causative agent. The duration of the incubation period was dependent of the age of the patient: 2.5 h in children under 10 yr of age, 3.5 h in older children and teenagers, and 7 h in adults. The soft cheese exhibited low levels of staphylococcal enterotoxin (SE) A (>6 ng of SEA/g of cheese) and high levels of staphylococcal enterotoxin D (>200 ng of SED/g of cheese). Counts of 10(7) cfu of coagulase-positive staphylococci per gram of cheese were detected, with 3 different Staphylococcus aureus strains being present at levels >10(6) cfu/g. The 3 strains were characterized using spa typing and a DNA microarray. An enterotoxin-producing strain exhibiting sea and sed was identified as the source of the outbreak. The strain was assigned to spa type t711 and clonal complex 8, and it exhibited genetic criteria consistent with the characteristics of a genotype B strain. This genotype comprises bovine Staph. aureus strains exclusively associated with very high within-herd prevalence of mastitis and has been described as a major contaminant in Swiss raw milk cheese. It is therefore highly likely that the raw milk used for Tomme production was heavily contaminated with Staph. aureus and that levels further increased due to growth of the organism and physical concentration effects during the cheese-making process. Only a few staphylococcal food poisoning outbreaks involving raw milk products have been described. Still, in view of this outbreak and the possible occurrence of other foodborne pathogens in bovine milk, consumption of raw milk and soft cheese produced from raw milk constitutes a health risk, particularly when young children or other members of sensitive populations are involved. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
    Journal of Dairy Science 02/2015; 98(5). DOI:10.3168/jds.2014-9123 · 2.55 Impact Factor
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    • "In Italy, as well as in different industrialized countries , raw milk consumption is becoming rather popular , thanks to the current trend toward " consuming natural " and " purchasing locally. " Enhanced nutritional qualities, taste, and health benefits are advocated as reasons for the increased interest in raw milk consumption (Oliver et al., 2009). Raw milk supporters claim the suitability of unpasteurized milk for the treatment or for the prevention of some diseases, even if no scientific evidence supports this notion (Oliver et al., 2005). "
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    ABSTRACT: In Italy, the sale of raw milk from vending machines has been allowed since 2004. Boiling treatment before its use is mandatory for the consumer, because the raw milk could be an important source of foodborne pathogens. This study fits into this context with the aim to evaluate the microbiological quality of 30 raw milk samples periodically collected (March 2013 to July 2013) from 3 vending machines located in Molise, a region of southern Italy. Milk samples were stored for 72 h at 4°C and then subjected to different treatments, such as boiling and microwaving, to simulate domestic handling. The results show that all the raw milk samples examined immediately after their collection were affected by high microbial loads, with values very close to or even greater than those acceptable by Italian law. The microbial populations increased during refrigeration, reaching after 72 h values of about 8.0 log cfu/mL for Pseudomonas spp., 6.5 log cfu/mL for yeasts, and up to 4.0 log cfu/mL for Enterobacteriaceae. Boiling treatment, applied after 72 h to refrigerated milk samples, caused complete decontamination, but negatively affected the nutritional quality of the milk, as demonstrated by a drastic reduction of whey proteins. The microwave treatment at 900 W for 75 s produced microbiological decontamination similar to that of boiling, preserving the content in whey proteins of milk. The microbiological characteristics of raw milk observed in this study fully justify the obligation to boil the raw milk from vending machines before consumption. However, this study also showed that domestic boiling causes a drastic reduction in the nutritional value of milk. Microwave treatment could represent a good alternative to boiling, on the condition that the process variables are standardized for safe domestic application.
    Journal of Dairy Science 04/2014; 97(6). DOI:10.3168/jds.2013-7744 · 2.55 Impact Factor
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    • "Technology Methodology Features Planar-array technology NRL array biosensor, PASA biosensor, SPR-based biosensor Short measurement times, automation, reduced sample volumes and high sensitivity Lateral flow devices (LFDs) or dipstick assays Qualitative, semi-quantitative and to some extent quantitative monitoring in resource-poor or non-laboratory environments Suspension-array technology Flow cytometry: xMAP technology in the MAGPIX instrument Low-cost, compact, rugged Nanoparticles and quantum dots Increased sensitivity, multiplexing capabilities, reduced costs, simple handling and short assay times milk processing. Most food safety hazards are introduced into the dairy production chain at the dairy farm via feed, environment or farm conditions (Jooste & Anelich, 2008; Oliver et al., 2009 "
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    ABSTRACT: Decision support systems (DSS) for controlling multiple food safety hazards in raw milk production have not yet been developed, but the underlying components are fragmentarily available. This article presents the state-of-the-art of essential DSS elements for judging food safety compliance of raw milk. The DSS elements include data identification at critical points in the supply chain, an information management system, and data exchange. Based on these elements, a concept for further development of a DSS is presented. These elements have to be integrated in the dairy chain to prevent inefficient sampling and analysis. Such a DSS would enhance food safety.
    Trends in Food Science & Technology 10/2013; 34(2):137–145. DOI:10.1016/j.tifs.2013.10.001 · 4.65 Impact Factor
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