An assessment of the hygiene status and incidence of foodborne pathogens on food contact surfaces in the food preparation facilities of schools

Identification of Salmonella Enteritidis, Salmonella Typhimurium, Bacillus cereus, Bacillus subtilis, and Clostridium perfringens in hospital food

Despite conducting studies to investigate food contamination in hospitals in different parts of Iran in recent years, there have been no reliable studies to identify Salmonella Enteritidis, Salmonella Typhimurium, Bacillus cereus, Bacillus subtilis, and Clostridium perfringens in hospital food in Mashhad. Therefore, this study was conducted with the aim of investigating some major foodborne pathogens in hospital food. In this study, 360 food samples were randomly selected from 12 different menus from 13 hospitals affiliated with Mashhad University of Medical Sciences, Mashhad, Iran. Microbial culture methods for the recovery/isolation or enumeration of Salmonella spp., Bacillus spp. and C. perfringens as well as toxinotyping of C. perfringens using the PCR method were performed. B. cereus and C. perfringens were detected in 4 out of 360 food samples, 2 (0.55%) of which were B. cereus and, the remaining 2 (0.55%) were C. perfringens; B. subtilis was not detected in any of the food samples. Furthermore, Salmonella was found in 21 (5.82%) food samples, 12 (3.33%) of which were S. Typhimurium, 4 (1.11%) were S. Enteritidis, and 5 (1.38%) belonged to other Salmonella species. The most contaminated foods were salad, kebab, and rice samples, which accounted for 36%, 16%, and 12% of the contaminated foods, respectively. In our study, two strains of S. Typhimurium and S. Enteritidis, were the primary causative agents of food contamination among the investigated pathogens. More stringent control measures should be implemented in hospital catering, particularly for unprocessed foods such as salads.

Optical detection and enumeration of Escherichia coli and Salmonella enterica using a low-magnification light microscope

A rapid and cost-effective method for detecting bacterial cells from surfaces is critical to food safety, clinical hygiene, and pharmacy quality. Herein, we established an optical detection method based on a gold chip coating with 3-mercaptophenylboronic acid (3-MPBA) to capture bacterial cells, which allows for the detection and quantification of bacterial cells with a standard light microscope under low-magnification (10×) objective lens. Then, integrate the developed optical detection method with swab sampling to detect bacterial cells loading on stainless-steel surfaces. Using Salmonella enterica (SE1045) and Escherichia coli (E. coli OP50) as model bacterial cells, we achieved a capture efficiency of up to 76.0 ± 2.0 % for SE1045 cells and 81.1 ± 3.3 % for E. coli OP50 cells at 103 CFU/mL upon the optimized conditions, which slightly decreased with the increasing bacterial concentrations. Our assay showed good linear relationships between the concentrations of bacterial cells with the cell counting in images in the range of 103 -107 CFU/mL for SE1045, and 103 -108 CFU/mL for E. coli OP50 cells. The limit of detection (LOD) was 103 CFU/mL for both SE1045 and E. coli OP50 cells. A further increase in sensitivity in detecting E. coli OP50 cells was achieved through a heat treatment, enabling the LOD to be reduced as low as 102 CFU/mL. Furthermore, a preliminary application succeeded in assessing bacterial contamination on stainless-steel surfaces following integration with the approximately 40 % recovery rate, suggesting prospects for evaluating the bacteria from surfaces. The entire process was completed within around 2 h, costing merely a few dollars per sample. Considering the low cost of standard light microscopes, our method holds significant potential for practical industrial applications in bacterial contamination control on surfaces, especially in low-resource settings.

Antibacterial Activity of Oregano (Origanum vulgare L.) Essential Oil Vapors against Microbial Contaminants of Food-Contact Surfaces

The antimicrobial effect of eight essential oils' vapors against pathogens and spoilage bacteria was assayed. Oreganum vulgare L. essential oil (OVO) showed a broad antibacterial effect, with Minimum Inhibitory Concentration (MIC) values ranging from 94 to 754 µg cm-3 air, depending on the bacterial species. Then, gaseous OVO was used for the treatment of stainless steel, polypropylene, and glass surfaces contaminated with four bacterial pathogens at 6-7 log cfu coupon-1. No viable cells were found after OVO treatment on all food-contact surfaces contaminated with all pathogens, with the exception of Sta. aureus DSM 799 on the glass surface. The antimicrobial activity of OVO after the addition of beef extract as a soiling agent reduced the Sta. aureus DSM 799 viable cell count by more than 5 log cfu coupon-1 on polypropylene and glass, while no viable cells were found in the case of stainless steel. HS-GC-MS analysis of the headspace of the boxes used for the antibacterial assay revealed 14 different volatile compounds with α-Pinene (62-63%), and p-Cymene (21%) as the main terpenes. In conclusion, gaseous OVO could be used for the microbial decontamination of food-contact surfaces, although its efficacy needs to be evaluated since it depends on several parameters such as target microorganisms, food-contact material, temperature, time of contact, and relative humidity.

"Blockchain technology in food safety and traceability concern to livestock products"

Livestock products share more than fifteen percent of total agri-foods traded worldwide. A global increase in food demand has increased the risk to food safety. Improvements in food quality, cold chain transit, and preservation are required for safe livestock products. Though, the food safety and regulation authorities demand complete food traceability from farm to fork, but in traditional supply chain it is ignored by fiddling with the transit paperwork and bill invoices. The process of supply chain reformation and activities linked to food recalls during food safety issues are insanely expensive and challenging. Traceability-driven food supply chain management is likely to implement novel technologies like the Internet of Things (IoT). The capability of the Blockchain era within the food sector is emerging with use cases across different regions, as shown via the growing number of studies. Credibility, efficiency, and safety are all improved when food products can be instantly traced from their point of origin through all points of contact on their way to the consumer. Blockchain assures a tamper-proof and transparent system that allows an innovative business solution, together with smart contracts. However, there are significant difficulties with the implementation of blockchain technology for food traceability. It necessitates more and more training platforms as well as trainers, who can make understanding and operability of this technology easy among ground-level participants and food entities. For the tactical application of this technology, it is essential to comprehend the legal and regulatory framework.

Inocuidad y calidad del agua y alimentación escolar: enfoques en América Latina y el Caribe

Objetivo.

Identificar los enfoques sobre la inocuidad y calidad del agua en los documentos que describen los programas de alimentación escolar en los países de América Latina y el Caribe (ALC).

Métodos.

Estudio descriptivo, transversal y exploratorio de los documentos sobre alimentación escolar en los países y territorios de ALC. Se realizó el análisis documental y se determinaron a priori cuatro categorías: “agua para el consumo”, “agua para la higiene”, “agua para la preparación”, y “agricultura local/familiar” según el uso del agua en la alimentación escolar. Los documentos fueron buscados durante 2018-2019 en los sitios web oficiales de los países y territorios de ALC, la Organización de las Naciones Unidas para la Alimentación y Agricultura y el Programa Mundial de Alimentos. Se obtuvieron las frecuencias absolutas y relativas de los datos cuantitativos y para los datos cualitativos se aplicó el análisis de contenido del tipo temático.

Resultados.

Se analizaron 114 documentos, de los cuales 29 eran elegibles. Los enfoques de las categorías “agua para el consumo”, “agua para la higiene” y “agua para la preparación” solo atribuían al agua la característica de ser potable. En la categoría “agricultura local/familiar” no se encontraron enfoques sobre el agua para el riego.

Conclusión.

Los documentos abordan el agua, pero no se centran en su inocuidad y calidad. Los gobiernos y autoridades locales deben revisar sus documentos y garantizar la unanimidad de los enfoques a partir del apoyo y diálogo intersectorial para alcanzar las metas de los Objetivos de Desarrollo Sostenible.

Cleaning and disinfection programmes in food establishments: a literature review on verification procedures

In food establishments, cleaning and disinfection programmes contribute to provide the environmental conditions that are necessary for the production of safe and healthy food. Compliance with validated programmes is evaluated through verification activities, in order to establish, through objective evidence, if they are implemented as they were written and if they are effective, achieving continuous improvement of the sanitation programmes. In accordance with the specific guidelines of each country, food companies set up their technical specifications and develop their own cleaning and disinfection programmes. Depending on the analytical method used, one of the main challenges was to establish a reasonable limit of acceptability according to the impact that each surface has on the safety and hygiene of the food that is prepared. This review was focused on the procedures implemented to verify the cleaning and disinfection programmes in food establishments. In particular, this study examines the methodologies used (audits and analytical methods), sites for the collection of samples, acceptance criteria and main findings. The results of the analysed studies constitute a scientific basis for designing or improving sanitation procedures and their verification in food companies, and also provide relevant information for food safety authorities.

Application of blockchain technology in food safety control：current trends and future prospects

Blockchain technology is a distributed ledger technology and is expected to face some difficulties and challenges in various industries due to its transparency, decentralization, tamper-proof nature, and encryption security. Food safety has been paid increasing attention in recent years with economic development. Based on a systematic literature critical analysis, the causes of food safety problems and the state-of-the-art blockchain technology overview, including the definition of blockchain, development history, classification, structure, characteristics, and main applications, the feasibility and application prospects of blockchain technology in plant food safety, animal food safety, and processed food safety were proposed in this review. Finally, the challenges of the blockchain technology itself and the difficulties in the application of food safety were analyzed. This study contributes to the extant literature in the field of food safety by discovering the excellent potential of blockchain technology and its implications for food safety control. Our results indicated that blockchain is a promising technology toward a food safety control, with many ongoing initiatives in food products, but many food-related issues, barriers, and challenges still exist. Nevertheless, it is expected to provide a feasible solution for controlling food safety risks.

Modeling the elimination of mature biofilms formed by Staphylococcus aureus and Salmonella spp. Using combined ultrasound and disinfectants

Biofilm formation by foodborne pathogens on food processing surfaces has contributed to numerous disease outbreaks and food recalls. We evaluated the following strategies for elimination of mature biofilm formed by Staphylococcus aureus and Salmonella spp. on stainless steel surfaces: acidic electrolyzed water (AEW), ozone water (OW), or ultrasound (40 kHz) alone, and combinations of ultrasound and disinfectants. The dynamics of elimination by combinations were determined using the Weibull and biphasic models. Treatment with AEW alone reduced the number of biofilm cells by approximately 3.0 log cfu/cm², whereas less than 0.8 log cfu/cm² of cells reduction was observed in biofilm exposed to OW or ultrasound alone, even with treatment for 20 min. The combination of AEW and ultrasound produced an obvious synergistic effect on biofilm reduction, achieving approximately 4.8 log cfu/cm² reduction in Salmonella spp. biofilm. Interestingly, the biphasic model was a better fit than the Weibull model for the elimination process of mature biofilm formed by both pathogens and subjected to a combination of ultrasound and AEW, as determined by smaller values of the statistical parameters RMSE and AIC, although both models could evaluate the dynamic processes. Our findings indicated that a combination of ultrasound and AEW could effectively reduce the biofilm formed by pathogens on food contact surfaces, and that the biphasic model could predict the number of residual cells after biofilm exposure to this intervention approach.

A preliminary study on the quality of street vended foods around a university in Kunming, China

The street vended foods (SVF) are very popular in China, particularly in highly adolescents populated regions such as schools. Food quality is a critical global issue, but there are few studies describe the quality assessment of SVF. In this study, the quality of SVF around a university in Kunming was evaluated, including the microbial quality, proximate composition, oil quality, and heavy metal content. Microbial results showed that the aerobic plate count (APC) and Escherichia coli (E. coli) counts ranged from 1.94 to 7.43 log CFU/g or ml, and 0.53 to 1.48 log CFU/g or ml, respectively. A portion of fried snack samples exceed the standard limit of acid value (AV) and peroxide value (POV), and the same result was observed in carbonyl group value (CGV), thiobarbituric acid (TBA) value, viscosity, and conductivity. The proximate composition of the fried snack samples varied widely, while the fat content was generally higher. The heavy metal analysis showed most samples met the safety standards, with the content of 12-51, 1-19, 12-73, and 11-88 μg/kg for As, Hg, Cd, and Pb, respectively. In conclusion, although the overall results of this study were satisfying, more attention should be given to the quality of SVF. Consequently, there is a need for additional measures to protect consumers, particularly young adults in college, from foodborne disease.