The aim of the study was to investigate which routines preschools had regarding food processing and if the routines were sufficient in order to the regulation. The aim was also to investigate if there were some difference in food processing depending on the employee´s education. The method used was an interview study of 20 preschools. The results indicated that the majority of the preschools had sufficient routines regarding temperature control of hot and cold lunches. Regarding measurement on deviant temperature, half of the preschools routines were sufficient. 55 % of the preschools had insufficient routines for temperature control in cold storage. Results indicate that it was differences in how often the employee´s control the temperature in food depended on the employee´s education. The conclusion is that a number of preschools had a capacity for improvement of their routines. The preschools have to work with prevention measures to create routines which is sufficient in order to the regulation.

Revised 06/2015; Originally published: 07/2006 / 3 pp. / Nutritious food is an important part of individual health and wellness. One way to ensure food is nutritious is to check the date on packages. The date is a guideline to help consumers use food when it is at its peak quality or before spoilage begins. Proper storage conditions and times are also essential in keeping healthy food safe to consume.

Salmonella enterica is a foodborne pathogen of major significance, and as such it has been extensively studied by researchers around the world. However, despite the numerous scientific publications on Salmonella, there are still many gaps in our understanding of its biology. One such gap is in the bacteria's interactions with invertebrate hosts, and in particular, oysters. Nearly 70 million pounds of oysters are consumed in the United States each year, and previous work in the Joens' laboratory found Salmonella in roughly 7% of the market oysters they sampled, with the majority of the isolates being the Newport serovar. The majority of oysters are consumed raw, which makes the presence of Salmonella within oysters a potentially significant food safety problem.To more closely examine the interactions between Salmonella and oysters, the Present Study developed a method to consistently and reproducibly raise oysters in a controlled laboratory environment in order to systematically expose them to enteric bacteria and quantify the amount of surviving bacteria at various time points after the initial exposure. Use of this model system throughout the Present Study led to four main conclusions.The first is that Salmonella enterica serovar Newport is capable of surviving in oysters for at least 60 days, from an average concentration of 3.7x103 CFU/g of oyster meat after 10 days, to over 102 CFU/g of oyster meat after 60 days. The second main conclusion is that the Newport serovar of Salmonella, which was found in such predominance in the earlier Joens' laboratory study, does not appear to have any special adaptations for survival within oysters, as other strains of Newport and other serovars of Salmonella survived equally well within our model. The third main conclusion, based on the results of immunohistochemistry, is that the relationship between Salmonella and oysters is not a transient interaction that is limited to the outside of the oyster's gut epithelium, but involves a long-term colonization inside the oysters' connective tissues. Because the survival of Salmonella in oysters could be of a pathogenic nature, the Present Study knocked out two key type III secretion systems (T3SS) found in two distinct Salmonella pathogenicity islands (SPI-1 and SPI-2) known to be critical for pathogenesis in mammalian hosts and examined their role in the bacteria's ability to survive within oysters. The results revealed that neither the SPI-1 nor the SPI-2 T3SS were necessary for Salmonella's survival in oysters, which led to the final conclusion of the Present Study that the nature of Salmonella's infection of oysters is fundamentally different than the pathogenesis that occurs in mammalian hosts and that further study of the mechanisms of the survival of Salmonella in oysters is needed to better understand the important and interesting relationship between a significant source of food and this common, and occasionally deadly, foodborne pathogen.

This study examined some of the environmental, physiological, and genetic factors or mechanisms which contribute to L. monocytogenes’ desiccation survival under food processing conditions. Desiccation experiments were carried out on stainless steel coupons stored at 43% RH, 15°C. The level of initial contamination had no impact (p>0.05), whereas the presence of a mature biofilm, prior osmoadaptation, and the presence of salt (5%) and lard (20-60%) on the SS coupons significantly (p<0.05) increased the bacterium’s desiccation survival. An Lm568 transposon mutant library was constructed to screen for novel genes involved in desiccation survival. Fifteen tolerant and 16 sensitive desiccation mutants were sequenced. Interrupted genes involved in motility and FA membrane modification were the most common in tolerant mutants whereas energy and membrane transport related genes were the most recognized in sensitive mutants. Lastly, a spontaneous desiccation resistant Lm568 variant was isolated, emphasizing the importance of understanding desiccation tolerance for food safety.

Best practices have previously been developed for beef slaughter and further processing operations with input from academic and industry leaders. Best practices for pork processors have not been developed, and those developed for the beef industry may not always be applicable to the operations of Small and Very Small establishments. Small and Very Small establishments warrant unique consideration in terms of financial and technological capabilities. While larger processors utilize multiple capital-intensive microbial interventions, smaller establishments often must rely on sanitary practices and more traditional interventions. In order to develop best practices for Small and Very Small pork slaughter and further processing establishments, a survey instrument seeking information on establishment and facility characteristics as well as current sanitary practices was distributed to Small and Very Small establishments in the Southwest region. Additionally, microbiological baselines were established for six Small and Very Small pork slaughter and/or further processing establishments to allow the efficacy of best practices to be assessed following implementation in each of the six plants. Survey responses revealed areas where best practice recommendation efforts may be focused, and microbiological baseline data provided insight to the condition of carcasses and environmental surfaces using current sanitary practices. Combined, the data reveal the opportunities for improvement in the food safety systems of Small and Very Small pork processing establishments.

No description available.

With a primary focus on Health Canada (HC) and the Canadian Food Inspection Agency (CFIA), this thesis describes the state of microbial related public involvement and risk communication undertakings. The findings show that HC engages with experts to a far greater extent than with the lay public and that HC has not upheld its stated commitment to transparency. Furthermore, both HC’s and the CFIA´s approach to risk communication is overly general, has failed to provide opportunities for dialogue with vulnerable groups and is not rooted in foodborne surveillance data. Public involvement in food safety governance would be improved if HC provided the lay public with a seat on advisory committees and improved its reporting methods. HC and the CFIA could also make improvements by creating opportunities for dialogue between officials and the general public, and by exploring the potential use of alternative risk communication vehicles, such as food labels.

Four focus groups were conducted in Kentucky to evaluate differences in the participants knowledge of safe food handling practices, where they obtained their knowledge, which source(s) they trusted to provide accurate food safety messages and the effectiveness of messages from three different sources. The sources of food safety messages compared by the focus groups were the Partnership for Food Safety Educations FightBAC! material, food safety materials developed by the American Dietetic Association and funded by ConAgra Foundation and food safety materials developed by the University of Kentucky. Each focus group represented a specific population, (A) limited resource parents (Louisville); (B) married males (Lexington); (C) mothers of young children (Danville); and, (D) females of varied age with background of Cooperative Extension Service sponsored consumer education in food preparation (Lexington). Follow up interviews were conducted through a telephone survey to inquire as to whether any food safety practices had been implemented since participation in the focus groups. The results of the interview revealed that participants expressed varying familiarity with safe food handling practices, varying understanding of the food safety messages and diverse acceptance and preference for the delivery mechanisms.

This thesis describes the results of three studies that used different measures of bacterial numbers in retail ground beef (n=309) collected across different locations in Saskatchewan within a one-year period (May 2011 – May 2012). The measurements were compared among three sample categories: 1 - ground beef displaying government inspection information on the label legend (n=126), 2 - originating from facilities licensed by local health regions and thus not subjected to government inspection (n=80), or 3 - processed and repackaged at the retail level thus carrying no government inspection information on the label (n=103). The first study reports baseline levels of bacteria in Saskatchewan retail ground beef as measured by traditional (total aerobic plate count (TAPC) and total E. coli plate count (TEPC)) and culture-independent methods (estimate of total bacterial load (TBL) by real-time quantitative polymerase chain reaction). After accounting for season and whether the samples were fresh or frozen at purchase, the lowest TAPC (log10 4.9 culture forming units per gram (cfu/g); 95% CI log10 4.7 to log10 5.1 cfu/g), TEPC (log10 0.58 cfu/g; 95% CI log10 0.39 to log10 0.77 cfu/g), and TBL in frozen ground beef (log10 4.5 target copies per gram (tc/g); 95% CI log10 4.0 to log10 4.9 tc/g) were observed in samples originating from federally regulated or provincially licensed facilities. In the second study, presence of known Enterobacteriaceae virulence factors (stx1, stx2, and eae) was detected by polymerase chain reaction (PCR) and compared between samples originating from three different regulatory and inspection environments as well as collected during different seasons of the year, and purchased fresh or frozen. One hundred and twelve out of all tested samples (n=308) were positive for the presence of at least one virulence marker with stx1 identified in 107 samples, stx2 - in 8, and eae - in 26. No significant associations were found between the virulence markers presence and sample category, state or season of purchase. The third study investigates the presence and diversity of Campylobacter spp. organisms in the same pool of 309 retail beef samples as detected by molecular methods. Fifty samples (16.2%) tested positive for Campylobacter genus-specific DNA in conventional PCR and 49 samples (15.9%) tested positive for at least one Campylobacter species DNA presence in real-time qPCR, but the crude agreement between the two methods was less than 50%. C. coli DNA presence was observed in 14 samples (4.5%), C. curvus – in 11 (3.6%), C. fetus – in 6 (1.9%), C. hyointestinalis – in 24 (7.8%), C. jejuni – in 12 (3.9%), C. rectus – in 6 (1.9%), and C. upsaliensis – in 9 (2.9%). There was no difference in the frequency of Campylobacter identified among the three sample categories, fresh and frozen, or samples purchased during the cold or warm season. These studies provide data on prevalence of bacteria in retail ground beef offered for sale in Saskatchewan and compare differences between samples presented to the consumer as originating from federally regulated or provincially licensed facilities, locally licensed facilities, or repackaged and processed directly at a retail outlet. The information on baseline levels of bacteria in retail ground beef and the comparisons among different categories can be used in prioritising food safety improvement efforts in Saskatchewan.

Listeria monocytogenes is the etiological agent of a life-threatening, opportunistic infection caused by the ingestion of contaminated foods. Although L. monocytogenes is divided into 13 serotypes, 98% of human illness is caused by serotype 1/2a, 1/2b and 4b strains, with serotype 4b accounting for almost all the major outbreaks of human listeriosis. The principle objective of this work was to develop surface-binding monoclonal antibodies (MAbs) highly specific for serotype 4b, as well as characterize their antigen targets to aid in the detection and isolation of serotype 4b strains using an antibody based procedure. To create such antibodies, mice were immunized with formalin killed whole cells of L. monocytogenes serotype 4b strain LI0521. A total of 15 MAbs reactive to serotype 4b isolates were shown to recognize a ~77 kDa surface antigen subsequently identified by mass spectrometry as surface associated autolysin, IspC. Epitope mapping experiments further revealed that each of the 15 MAbs bound to the cell wall binding GW domain of IspC and can be essentially divided into 4 major groups based on epitope localization. ELISA analysis of the reactivity of each of the MAbs with various L. monocytogenes serotypes indicated that several MAbs were 100% specific for serotype 4b isolates. Surface plasmon resonance experiments showed that the affinity constants for each of these MAbs fell within the range of 1.0 x 10-7 to 6.4 x 10-9 M. To determine whether IspC, shown to be well conserved among various serotype 4b strains, is a useful diagnostic marker with antibody-based methods, the expression of IspC was assessed in L. monocytogenes cultured under normal and stress conditions. A functional promoter directing the transcription of ispC gene was identified immediately upstream of the ispC open reading frame by constructing the promoterless lacZ gene fusion with the putative ispC promoter region and by 5'RACE analysis. Data obtained with the lacZ reporter gene system and immunofluorescent microscopy revealed that IspC is expressed on the cell surface under all growth conditions tested (temperature, osmotic stress, pH, ethanol, oxidative stress, anaerobic conditions, carbon source and enrichment media) that allow for cellular division, although the level of ispC gene expression varies. In addition, a significant effort were put into elucidating the hydrolytic bond specificity of IspC by HPLC and mass spectrometry analysis of muropeptides released from IspC-mediated hydrolysis of L. monocytogenes peptidoglycan (PG). The results demonstrated that IspC functions as an N-acetylglucosaminidase capable of cleaving the β-1,4-glycosidic bond of the PG glycan strand. Furthermore, IspC was more efficient at hydrolysing fully Nacetylated PG from a PG deacetylase gene (pgdA) deletion mutant of L. monocytogenes than partially de-N-acetylated wild-type PG, indicating that modification of PG by de-Nacetylation of GlcNAc residues renders PG resistant to IspC hydrolysis. In conclusion, the surface autolysin IspC with the N-acetylglucosaminidase activity is a novel diagnostic marker for the 4b serotype strains, which can be explored , in conjunction with specific MAbs developed here, for detection and isolation of L. monocytogenes serotype 4b strains directly from food, environmental and clinical samples with the need for minimal or no culture enrichment.