Survey on the occurrence of allergens on food-contact surfaces from school canteen kitchens

An expanded framework for Swab Touch Spray-Mass Spectrometry towards the detection of allergenic protein residues on food preparation surfaces

BACKGROUND

Ambient Mass Spectrometry (AMS) encompasses a group of techniques that have emerged as powerful strategies for direct, in-situ and high-throughput analysis, also in compliance with the principles of green analytical chemistry. Swab Touch Spray-Mass Spectrometry (Swab TS-MS) is a home-made AMS technique that involves the use of a medical swab as sampling tool and electrospray probe. To date, Swab TS-MS has been applied only for the analysis of small molecules, especially in forensic and medical fields, leaving the analysis of peptides and proteins still unexplored.

RESULTS

In the present study, the application framework of Swab TS-MS was expanded towards the detection of proteins, focusing on residues of allergenic ingredients as contaminants of food preparation surfaces. Lysozyme from chicken egg white was selected as case study of allergenic protein. Since none of the experimental conditions explored allowed the detection of intact lysozyme, a bottom-up procedure based on tryptic digestion for lysozyme detection by Swab TS-MS, operating in MS/high resolution (HR)MS tandem mode, was investigated. In parallel, liquid chromatography-tandem mass spectrometry was used to develop and characterize an in-situ digestion/swabbing strategy, allowing to reach a LOD value of 0.003 μg/cm2 of egg white powder consistent with that of lateral flow immunoassay technique. Finally, the developed in-situ digestion/swabbing procedure was coupled to the Swab TS-MS/HRMS method, permitting the direct analysis of egg white powder residues on stainless steel surfaces, reaching a LOD of 68 μg/cm2 egg white powder, corresponding to 2.4 μg/cm2 of lysozyme.

SIGNIFICANCE

This study should be intended as a first step for the application of Swab TS-MS technique in protein analysis: the developed in-situ digestion and sampling strategy suitable for Swab TS-MS direct analysis of food allergen has a valuable impact towards the availability of MS-based multiplexed detection tool useful for the development of efficient surface cleaning procedures.

Celiac Disease: Risks of Cross-Contamination and Strategies for Gluten Removal in Food Environments

Celiac disease (CD) is the chronic immune-mediated enteropathy of the small bowel, manifesting when exposure to gluten occurs in genetically predisposed individuals. Nowadays, the only treatment considered safe for CD is a gluten-free diet (GFD). However, one of the problems faced by celiac patients is the cross-contamination of gluten-free food when preparing meals, in addition to utensils, surfaces and equipment. This study aimed to evaluate cross-contamination in gluten-free products and strategies for removing gluten from cross-contamination in cooking environments. The selection of papers for this integrative review was carried out by searching different databases. Gluten cross-contamination is a global concern for celiac patients in food environments. Although some practices are positive, such as gluten labeling on processed food in several countries, it is crucial to promote good practices in food services around the world. Only a few studies showed effective results in removing gluten from surfaces and utensils; furthermore, sampling was limited, making it difficult to identify appropriate procedures to reduce cross-contamination. The variation in contamination in different kitchen environments also highlighted that celiac patients must continue paying attention to the methods used to prepare gluten-free food. More research is needed, especially into methods of removing gluten from surfaces and utensils, to ensure food safety for celiac patients in many food environments.

A spotlight on analytical prospects in food allergens: From emerging allergens and novel foods to bioplastics and plant-based sustainable food contact materials

The present review throws a spotlight on new and emerging food safety concerns in view of a well-established food allergen risk arising from global socio-economic changes, international trade, circular economy, environmental sustainability, and upcycling. Food culture globalization needs harmonization of regulations, technical specifications, and reference materials towards mutually recognised results. In parallel, routine laboratories require high-throughput reliable analytical strategies, even in-situ testing devices, to test both food products and food contact surfaces for residual allergens. Finally, the currently neglected safety issues associated to possible allergen exposure due to the newly proposed bio- and plant-based sustainable food contact materials require an in-depth investigation.

SANITASI ALERGEN PADA PROSES PRODUKSI BISKUIT DALAM UPAYA MENGURANGI RESIDU ALERGEN TELUR

Food allergy is a hypersensitive response to food, generally protein, triggered by body immune system. These responses can be mild, however in very rare cases may cause severe reactions and life threatening known as called anaphylaxis. Food allergy has been one of the main factors for product recall. It can happen due to many reasons, such as product package labeling fault, raw material labeling fault and cross contamination. Validation of the effectiveness of cleaning and sanitation process become a critical point to minimize cross contamination. This study aimed to determine the optimum chemical concentration and contact time to eliminate egg residue in biscuit production cleaning process, obtain valid and verified cleaning procedures, and produce cleaning procedures that can be implemented in a production line. The result showed that physical cleaning/pre-cleaning for 30 minute and using 1% (v/v) concentration of caustic based polybrite chemical cleaning for 3-minute contact time can effectively eliminate the egg residue on stainless steel and polyurethane surface equipment. Food contact surface material and product characteristics (wet dough, dry biscuit) affected the number of egg residue on the equipment. Packing area with food contact surface equipment made from stainless steel is not considered critical area for allergen sanitation. It is shown that prior to sanitation process, analysis of egg allergen residue has already given negative result. Validation process can prove the effectiveness of allergen sanitation process to prevent potential egg allergen cross contamination in biscuit production.

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.

Allergen Removal and Transfer with Wiping and Cleaning Methods Used in Retail and Food Service Establishments

ABSTRACT

Preventing the transfer of allergens from one food to another via food contact surfaces in retail food environments is an important aspect of retail food safety. Existing recommendations for wiping and cleaning food contact surfaces is mainly focused on preventing microorganisms, such as bacteria and viruses, from contaminating foods. The effectiveness of these wiping and cleaning recommendations for preventing the transfer of food allergens in retail and food service establishments remains unclear. This project investigated (i) allergen removal from surfaces by wiping with paper wipes, terry cloth, and alcohol quaternary ammonium chloride (quat) sanitizing wipes; (ii) cleaning of allergen-contaminated surfaces by using a wash-rinse-sanitize-air dry procedure; and (iii) allergen transfer from contaminated wipes to multiple surfaces. Food contact surfaces (stainless steel, textured plastic, and maple wood) were contaminated with peanut-, milk- and egg-containing foods and subjected to various wiping and cleaning procedures. For transfer experiments, dry paper wipes or wet cloths contaminated with allergenic foods were wiped on four surfaces of the same composition. Allergen-specific lateral flow devices were used to detect the presence of allergen residues on wiped or cleaned surfaces. Although dry wipes and cloths were not effective for removing allergenic foods, terry cloth presoaked in water or sanitizer solution, use of multiple quat wipes, and the wash-rinse-sanitize-air dry procedure were effective in allergen removal from surfaces. Allergens present on dry wipes were transferred to wiped surfaces. In contrast, minimal or no allergen transfer to surfaces was found when allergen-contaminated terry cloth was submerged in sanitizer solution prior to wiping surfaces. The full cleaning method (wash-rinse-sanitize-air dry) and soaking the terry cloth in sanitizer solution prior to wiping were effective at allergen removal and minimizing allergen transfer.

HIGHLIGHTS

Food allergy and food intolerance knowledge of foodservice workers in Hungarian schools

To provide food for children with food allergy or food intolerances represents an increasingly important role in school catering services. The number of children with food intolerances is growing continuously; therefore, it is necessary to improve the knowledge of foodservice workers, who are responsible for food provision in school catering units in relation with food intolerances, food allergies. The main goal of our research is to assess and analyze the knowledge of food service workers and food handlers on food intolerances and to determine those factors, which may influence their knowledge. Our research was conducted by using paper and pencil questionnaires. The mean of test results was 89,16% while deviation was 12,26%. There were no correlations between the test results and respondents”™ education level, age group and the number of years working in food catering sector, and only partial correlation was detected with the job of the respondents. Based on the answers the food handling techniques of diet foods represented the poorest results. Our findings proved that the knowledge and food handling practice of food handlers regarding food intolerances and the preparation of diet meals should be improved.

Effectiveness of proteolytic enzymes to remove gluten residues and feasibility of incorporating them into cleaning products for industrial purposes

The development of protocols for efficient gluten elimination is one of the most critical aspects of any allergen management strategy in the industry. The suitability of different proteolytic enzymes to be included in a cleaning formulation that allows the effective elimination of gluten residues was studied. Alcalase (ALC), neutrase (NEUT) and flavourzyme (FLAV) were selected from in silico analysis. The presence of 1% (v/v) of linear alkylbenzene sulphonate (LAS), a common anionic detergent, improved the gluten solubility, which may favour its elimination. Chromatographic analysis showed that the three enzymes studied were able to hydrolyse gluten in the presence of LAS. The highest percentage of short peptides (< 5 kDa) was achieved with ALC, what increases the probability of reducing the gluten antigenicity. Besides, in the presence of ALC and detergent LAS have detected the lowest levels of gluten with ELISA kits. So, effective amounts of ALC and LAS were added to a cleaning formulation, where its proteolytic activity was maintained above 90% after 37 days at 4 °C and 25 °C (under dark). Preliminary validation of the effectiveness enzymatic cleaning formulation to hydrolyse gluten was performed in a ready-to-eat/frozen food company, in which previous episodes of cross-contamination with gluten have been detected. The gluten content decreased to values below 0.125 μg/100 cm² when the cleaning formulation was tested on different surfaces with different cleaning protocols, demonstrating the high suitability of the enzymatic cleaning formulation developed.