Temperature increase of foods in car trunk and the potential hazard for microbial growth

Predictive modeling of Salmonella spp. growth behavior in cooked and raw chicken samples: Real-time PCR quantification approach and model assessment in different handling scenarios

The increasing prevalence of Salmonella contamination in poultry meat emphasizes the importance of suitable predictive microbiological models for estimating Salmonella growth behavior. This study was conducted to evaluate the potential of chicken juice as a model system to predict the behavior of Salmonella spp. in cooked and raw chicken products and to assess its ability to predict cross-contamination scenarios. A cocktail of four Salmonella serovars was inoculated into chicken juice, sliced chicken, ground chicken, and chicken patties, with subsequent incubation at 10, 15, 20, and 25°C for 39 h. The number of Salmonella spp. in each sample was determined using real-time polymerase chain reaction. Growth curves were fitted into the primary Baranyi and Roberts model to obtain growth parameters. Interactions between temperature and growth parameters were described using the secondary Ratkowsky's square root model. The predictive results generated by the chicken juice model were compared with those obtained from other chicken meat models. Furthermore, the parameters of the chicken juice model were used to predict Salmonella spp. numbers in six worst-case cross-contamination scenarios. Performance of the chicken juice model was evaluated using the acceptable prediction zone from -1.0 (fail-safe) to 0.5 (fail-dangerous) log. Chicken juice model accurately predicted all observed data points within the acceptable range, with the distribution of residuals being wider near the fail-safe zone (75%) than near the fail-dangerous zone (25%). This study offers valuable insights into a novel approach for modeling Salmonella growth in chicken meat products, with implications for food safety through the development of strategic interventions. PRACTICAL APPLICATION: The findings of this study have important implications in the food industry, as chicken juice could be a useful tool for predicting Salmonella behavior in different chicken products and thus reducing the risk of foodborne illnesses through the development of strategic interventions. However, it is important to recognize that some modifications to the chicken juice model will be necessary to accurately mimic all real-life conditions, as multiple factors particularly those related to food processing can vary between different products.

Salmonella spp. in poultry production-A review of the role of interventions along the production continuum

Salmonella is a significant pathogen of human and animal health and poultry are one of the most common sources linked with foodborne illness worldwide. Global production of poultry meat and products has increased significantly over the last decade or more as a result of consumer demand and the changing demographics of the world's population, where poultry meat forms a greater part of the diet. In addition, the relatively fast growth rate of birds which is significantly higher than other meat species also plays a role in how poultry production has intensified. In an effort to meet the greater demand for poultry meat and products, modern poultry production and processing practices have changed and practices to target control and reduction of foodborne pathogens such as Salmonella have been implemented. These strategies are implemented along the continuum from parent and grandparent flocks to breeders, the farm and finished broilers to transport and processing and finally from retail to the consumer. This review focuses on common practices, interventions and strategies that have potential impact for the control of Salmonella along the poultry production continuum from farm to plate.

Beef Handling Practices Among Consumers in the U.S. Virgin Islands

U.S. Virgin Islands (USVI) imports more than 95% of its food. Transportation limitations throughout the territory's supply chain can make temperature control of protein foods challenging for consumers. This study aimed to characterize the beef handling practices used by consumers in USVI to determine any educational needs. Printed and online surveys (n = 620 total) were disseminated in USVI through extension agents and local media sources. Three hundred and thirty-four consumers completed a 30-question food handling questionnaire on consumption patterns and food handling from purchasing to their kitchen. Frequencies and Pearson chi-square tests of independence were performed. Beef ranked second among the different meat types consumed, 92% of consumers bought beef from grocery stores, and 55% removed beef from shelves immediately after entering the store. When shopping, 59.1% of respondents always checked the use-by/freeze-by dates of beef, 46.3% always separated beef from other foods, but only 27.5% always used insulated bags. Eighty-three percent of consumers returned home within 1 h of shopping, 92% took less than 30 min to store groceries in either a freezer or refrigerator (98%) and during power outages, 45.1% maintained cold temperatures of beef. Seventy-two percent of consumers washed their hands for more than 10 s, but 33% of those from households with a vulnerable person did not use soap to wash their hands and dried them with reusable towels. When cooking, 44.6% of consumers thawed beef within the temperature danger zone, 80.1% did not check the temperature of beef for doneness, and 34 respondents cooked hamburgers below 160°F. Future consumer food safety education initiatives in the USVI should address hand hygiene among food preparers in homes with vulnerable persons, temperature control practices by promoting the use of insulated bags, safe meat thawing techniques, and the use of thermometers during cooking.

Assessing the Risk of Seasonal Effects of Campylobacter Contaminated Broiler Meat Prepared In-Home in the United States

Campylobacter has consistently posed a food safety issue in broiler meat. This study aimed to create a quantitative microbial risk assessment model from retail to consumption, designed to evaluate the seasonal risk of campylobacteriosis associated with broiler meat consumption in the United States. To achieve this, data was gathered to build distributions that would enable us to predict the growth of Campylobacter during various stages such as retail storage, transit, and home storage. The model also included potential fluctuations in concentration during food preparation and potential cross-contamination scenarios. A Monte Carlo simulation with 100,000 iterations was used to estimate the risk of infection per serving and the number of infections in the United States by season. In the summer, chicken meat was estimated to have a median risk of infection per serving of 9.22 × 10^-7 and cause an average of about 27,058,680 infections. During the winter months, the median risk of infection per serving was estimated to be 4.06 × 10^-7 and cause an average of about 12,085,638 infections. The risk assessment model provides information about the risk of broiler meat to public health by season. These results will help understand the most important steps to reduce the food safety risks from contaminated chicken products.

Practical in-storage interventions to control foodborne pathogens on fresh produce

Although tremendous efforts have been made to ensure fresh produce safety, various foodborne outbreaks and recalls occur annually. Most of the current intervention strategies are evaluated within a short timeframe (less than 1 h), leaving the behavior of the remaining pathogens unknown during subsequent storages. This review summarized outbreak and recall surveillance data from 2009 to 2018 obtained from government agencies in the United States to identify major safety concerns associated with fresh produce, discussed the postharvest handling of fresh produce and the limitations of current antimicrobial interventions, and reviewed the intervention strategies that have the potential to be applied in each storage stage at the commercial scale. One long-term (up to 12 months) prepacking storage (apples, pears, citrus among others) and three short-term (up to 3 months) postpacking storages were identified. During the prepacking storage, continuous application of gaseous ozone at low doses (≤1 ppm) is a feasible option. Proper concentration, adequate circulation, as well as excess gas destruction and ventilation systems are essential to commercial application. At the postpacking storage stages, continuous inhibition can be achieved through controlled release of gaseous chlorine dioxide in packaging, antimicrobial edible coatings, and biocontrol agents. During commercialization, factors that need to be taken into consideration include physicochemical properties of antimicrobials, impacts on fresh produce quality and sensory attributes, recontamination and cross-contamination, cost, and feasibility of large-scale production. To improve fresh produce safety and quality during storage, the collaboration between researchers and the fresh produce industry needs to be improved.

Changes in Consumers' Food Purchase and Transport Behaviors over a Decade (2010 to 2019) Following Health and Convenience Food Trends

Although consumers’ food purchase/transport have been reported as causes of food safety risks, there is a lack of empirical data that are feasible to identify persistent and emerging risky behaviors of consumers. This longitudinal trend study consists of individual consumer surveys in 2010 (n = 609) and 2019 (n = 605) to analyze changes in risky behaviors linked to food purchase/transport over a decade. Overall, the results identified purchase/transport time and purchase order as the emerging and unchanged risk factors, respectively. Consumers’ preferences into channels for purchase (large discount stores rather than small/traditional markets) and transport (using cars or delivery) implied the convenience as the noticeable trend. Whereas, unexpected increases in purchase/transport time highlighted the underestimated risks in long-term exposure of foods under inadequate temperature. Food should not be exposed to danger zones > 1–2 h, but consumers might be unaware of the risk especially for preferred channels (e.g., 77 and 36 min. are required for purchase and transport from large discount stores, respectively). In the case of unchanged risky behavior, more than half of consumers in both surveys did not follow proper purchasing orders. Our findings highlight the necessity for novel countermeasures and the improvement of current consumer guidelines against emerging and unchanged risky behaviors, respectively.

Combined influence of multiple climatic factors on the incidence of bacterial foodborne diseases

Information regarding the relationship between the incidence of foodborne diseases (FBD) and climatic factors is useful in designing preventive strategies for FBD based on anticipated future climate change. To better predict the effect of climate change on foodborne pathogens, the present study investigated the combined influence of multiple climatic factors on bacterial FBD incidence in South Korea. During 2011-2015, the relationships between 8 climatic factors and the incidences of 13 bacterial FBD, were determined based on inpatient stays, on a monthly basis using the Pearson correlation analyses, multicollinearity tests, principal component analysis (PCA), and the seasonal autoregressive integrated moving average (SARIMA) modeling. Of the 8 climatic variables, the combination of temperature, relative humidity, precipitation, insolation, and cloudiness was significantly associated with salmonellosis (P<0.01), vibriosis (P<0.05), and enterohemorrhagic Escherichia coli O157:H7 infection (P<0.01). The combined effects of snowfall, wind speed, duration of sunshine, and cloudiness were not significant for these 3 FBD. Other FBD, including campylobacteriosis, were not significantly associated with any combination of climatic factors. These findings indicate that the relationships between multiple climatic factors and bacterial FBD incidence can be valuable for the development of prediction models for future patterns of diseases in response to changes in climate.

Effects of Domestic Storage and Thawing Practices on Salmonella in Poultry-Based Meat Preparations

Among consumer food handling practices, time-temperature abuse has been reported as one of the most common contributory factors in salmonellosis outbreaks where the evidence is strong. The present study performed storage tests of burgers, sausages, and kebabs and investigated (i) the effect of refrigerator temperatures (4°C versus 8 or 12°C, which were the temperatures recorded in 33 and 3%, respectively, of domestic refrigerators in Italy), with or without prior temperature abuse (25°C for 2 h, simulating transport of meats from shop to home), and (ii) the impact of the thawing method (overnight in the refrigerator at 8°C versus on the kitchen countertop at 23°C) on the presence and numbers of Salmonella bacteria. Storage tests were carried out on naturally or artificially (Salmonella enterica serovar Typhimurium at ca. 10 CFU/g) contaminated products, while freezing-thawing tests were conducted only on artificially contaminated products (Salmonella Typhimurium at ca. 10, 100, and 1,000 CFU/g). The results from the artificially contaminated products showed significant (P < 0.05) growth of Salmonella Typhimurium at 12°C (i.e., from ca. 8 most probable number [MPN]/g to > 710 MPN/g) in kebabs after 7 and 10 days but more moderate growth in sausages (i.e., from ca. 14 MPN/g to a maximum of 96 MPN/g after 9 days of storage). Storage of naturally contaminated burgers or sausages (contamination at or below 1 MPN/g) at 4, 8, or 12°C and a short time of temperature abuse (2 h at 25°C) did not facilitate an increase in the presence and numbers of Salmonella bacteria. Thawing overnight in the refrigerator led to either a moderate reduction or no change of Salmonella Typhimurium numbers in burgers, sausages, and kebabs. Overall, this study showed that domestic storage and thawing practices can affect food safety and that time-temperature abuse can cause a substantial increase of Salmonella numbers in some types of poultry-based meat preparations, highlighting that efforts for the dissemination of consumer guidelines on the correct storage and handling of meats need to be continued.

Development of Safe Food Handling Guidelines for Korean Consumers

The purpose of this study was to develop guidelines for Korean consumers with regard to safe food handling practices at home by identifying current food handling issues. Korean consumers' behaviors regarding their safe food handling were identified via survey questionnaires that included items on individual hygiene practices, prepreparation steps when cooking, the cooking process, and the storage of leftover foods. The subjects were 417 Korean parents with elementary school children living in Seoul and Gyeonggi Province in the central area of Korea. The survey results revealed gaps between the knowledge or practices of Korean consumers and scientific evidence pertaining to safe food handling practices. Based on these findings, a leaflet on safe food handling guidelines was developed in accordance with Korean food culture. These guidelines suggest personal hygiene practices as well as fundamental principles and procedures for safe food handling from the stage of food purchase to that of keeping leftover dishes. A pilot application study with 50 consumers revealed that the guidelines effectively improved Korean consumers' safe food handling practices, suggesting that they can serve as practical educational material suitable for Korean consumers.

Contamination of tomatoes with coliforms and Escherichia coli on farms and in markets of northwest Nigeria

Although recent reports indicated that produce contamination with foodborne pathogens is widespread in Nigeria, the sources and magnitude of microbial contamination of fruits and vegetables on farms and in markets have not been thoroughly identified. To ascertain possible pathways of contamination, the frequency and magnitude of coliform and Escherichia coli contamination of tomatoes produced in northwest Nigeria was assessed on farms and in markets. Eight hundred twenty-six tomato fruit samples and 36 irrigation water samples were collected and assessed for fecal indicator organisms. In addition, the awareness and use of food safety practices by tomato farmers and marketers were determined. Median concentration of coliforms on all field- and market-sourced tomato fruit samples, as well as in irrigation water sources, in Kaduna, Kano, and Katsina states exceeded 1,000 most probable number (MPN) per g. Median E. coli counts from 73 (17%) of 420 field samples and 231 (57%) of 406 market tomato fruit samples exceeded 100 MPN/g. Median E. coli concentrations on tomato fruits were higher (P < 0.01) in the rainy season (2.45 Log MPN/g), when irrigation was not practiced than in the dry (1.10 Log MPN/g) and early dry (0.92 Log MPN/g) seasons. Eighteen (50%) of 36 irrigation water samples had E. coli counts higher than 126 MPN/100 ml. Median E. coli contamination on market tomato fruit samples (2.66 Log MPN/g) were higher (P < 0.001) than those from tomatoes collected on farms (0.92 Log MPN/g). Farmers and marketers were generally unaware of the relationship between food safety practices and microbial contamination on fresh produce. Good agricultural practices pertaining to food safety on farms and in local markets were seldom used. Adoption of food safety practices on-farm, during transport, and during marketing could improve the microbial quality of tomatoes available to the public in this region of the world.

Acute oral safety study of sodium caseinate glycosylated via maillard reaction with galactose in rats

In order to potentially use sodium caseinate (SC) glycated with galactose (Gal) in the food industry as a new functional ingredient with proved technological and biological properties, an evaluation of oral acute toxicity has been carried out. An acute safety study with SC-Gal glycoconjugates in the Wistar rat with a single oral gavage dose of 2,000 mg/kg of body weight was conducted. The SC-Gal glycoconjugates were well tolerated; no adverse effects or mortality was observed during the 2-week observation period. No abnormal signs, behavioral changes, body weight changes, or alterations in food and water consumption occurred. After this period, no changes in hematological and serum chemistry parameters, organ weights, or gross pathology or histopathology were detected. It was concluded that SC-Gal glycoconjugates obtained via the Maillard reaction were well tolerated in rats at an acute oral dose of 2,000 mg/kg of body weight. The SC-Gal glycoconjugates have a low order of acute toxicity, and the oral 50 % lethal dose for male and female rats is in excess of 2,000 mg/kg of body weight.

Behavioral risk factors associated with listeriosis in the home: a review of consumer food safety studies

Listeria monocytogenes causes human listeriosis, which is associated with the highest hospitalization and mortality rates of all foodborne illnesses. In recent years, the incidence of listeriosis has doubled in Europe, almost exclusively among older adults (≥ 60 years of age). Food safety factors associated with increased risk of listeriosis include lack of adherence to "use by" dates and ineffective refrigerated storage of foods. Consequently, older adult consumers' implementation of safe food practices should be evaluated. This article is a review of consumer food safety cognitive and behavioral data relating to risk factors associated with listeriosis in the home as reported in 165 consumer food safety studies. Overall, only 41% of studies included assessment of consumer cognitive or behavioral data associated with listeriosis; of these studies 59% included data on safe refrigeration, 54% included data on storage time for opened ready-to-eat foods, and 49% included data on adherence to use-by dates. In most (83%) of the studies, survey-based data collection methods (questionnaires/interviews) were used; thus, the majority of findings were based on self-report (74%) and knowledge (44%). Observation (31%) and focus groups (12%) were less commonly used, resulting in a lack of actual behaviors and attitudinal data relating to listeriosis risk factors. Only 7% of studies included food safety data for older adults. Although older adults may fail to implement recommended practices, this review reveals a need for in-depth research to determine food safety attitudes and actual behaviors of older adults in conjunction with knowledge and selfreport of practices linked to increased risks of listeriosis. Such data combined with review findings would inform targeted food safety education to reduce risks associated with listeriosis in the home.