Science Direct
Campylobacteriosis is an emerging foodborne illness of high relevance and implication for public health and is frequently linked to the consumption of inadequately prepared poultry. Despite extensive scientific efforts to find possibilities to eradicate the bacteria at the production stage and particular measures currently implemented, it has not been possible to provide Campylobacter-free poultry to the consumer. Therefore, it is important to inform consumers about the risk and appropriate mitigation measures. The primary goal of this study was to investigate Swiss consumers’ knowledge of pathogenic bacteria and mitigation measures and domestic food safety behaviour. Thus, the relevant information that should be included in risk communications could be identified. The secondary goal was to identify target groups for risk communication who exhibit particularly unsafe behaviour when preparing poultry. These research questions were investigated in a mixed-method study, combining findings from a qualitative pre-study with the quantitative findings from a survey administered to a large sample of people who occasionally cook poultry (N = 465). The core of the questionnaire was behaviour and knowledge scales, as well as variables assessing risk perception and cooking experiences. Despite a high overall level of knowledge about pathogenic bacteria in poultry and mitigation measures, prevalent misconceptions and knowledge gaps were uncovered. Major violations of food safety behaviour were reported related to avoiding cross-contamination. Lack of specific knowledge and personal risk perception were estimated to be central reasons for violations of food safety behaviour during poultry preparation. Three different consumer groups were identified and analysed according to socio-demographics and socio-psychological variables: unsafe cooks, who reported overall unsafe behaviour, intermediate cooks, who reported some unsafe behaviour, and safe cooks, who reported only little food safety violations. As a last step, the study’s findings were discussed in terms of implications for further research and risk communication practice by isolating the most important knowledge and behaviour aspects. Furthermore, targeted risk communication strategies are considered for the three different target groups.
Science Direct
The purpose of this study was to investigate the effectiveness of ultraviolet-C (UV-C) light inactivation as affected by the location of pathogens on the surface and at stem scars of whole grape tomatoes. A mixed bacterial cocktail containing a three strain mixture of Escherichia coli O157:H7 (C9490, E02128 and F00475) and a three serotype mixture of Salmonella enterica (S. Montevideo G4639, S. Newport H1275, and S. Stanley H0558) were used. Tomatoes were spot inoculated using approximately 100 μL of inocula to achieve a population of about 107±1 CFU/tomato. Additionally, the effects of treatment on color, texture, lycopene content, and background microbial loads during post UV-C storage at 4 °C for 21 days were determined. Results showed that UV-C doses of 0.60–6.0 kJ/m2 resulted in 2.3–3.5 log CFU per fruit reduction of E. coli O157:H7 compared to 2.15–3.1 log CFU per fruit reduction for Salmonella on the surfaces. Under the same conditions, log reductions achieved at stem scar were 1.7–3.2 logs CFU for E. coli O157:H7 and 1.9–2.8 logs CFU for Salmonella. The treatment was effective in controlling native microbial loads during storage at 4 °C as the total aerobic mesophilic organisms (PCA) and anaerobic lactic acid bacteria (LAB) counts of treated tomatoes were significantly (p < 0.05) lower during storage compared to the control group and the yeast and mold populations were reduced significantly below the detection limit. Furthermore, the firmness of tomato and its color was not affected by the UV-C doses during storage. UV-C radiation could potentially be used for sanitizing fresh tomatoes and extending shelf-life. The results of this study indicate that the specific location of pathogens on the produce influences the effectiveness of UV-C treatment, which should be taken into consideration for the design of UV-C systems for produce sanitization.
ESA
Stormwater and agricultural runoff frequently contain agrochemicals, fecal indicator bacteria (FIB) and zoonotic pathogens. Entry of such contaminants into aquatic ecosystems may affect ecology and human health. This study tested the hypothesis that the herbicide atrazine and the fungicide chlorothalonil indirectly affect the survival of FIB (Escherichia coli and Enterococcus faecalis) and a pathogen (E. coli O157:H7) by altering densities of protozoan predators or by altering competition from autochthonous bacteria. Streptomycin-resistant E.coli, Ent. faecalis, and E. coli O157:H7 were added to microcosms composed of Florida river water containing natural protozoan and bacterial populations. FIB, pathogen, and protozoan densities were monitored over six days. Known metabolic inhibitors cycloheximide and streptomycin were used to inhibit autochthonous protozoa or bacteria, respectively. The inhibitors made it possible to isolate the effects of predation or competition on survival of allochthonous bacteria, and each treatment increased the survival of FIB and pathogens. Chlorothalonil’s effect was similar to that of cycloheximide, significantly reducing protozoan densities and elevating densities of FIB and pathogens relative to the control. Atrazine treatment did not affect protozoan densities, but, through an effect on competition, resulted in significantly greater densities of Ent. faecalis and E. coli O157:H7. Hence, by reducing predaceous protozoa and bacterial competitors that facilitate purifying waterbodies of FIBs and human pathogens, chlorothalonil and atrazine indirectly diminished an ecosystem service of freshwater.
FoodWorld 