Food safety challenges associated with traditional foods in German-speaking regions

The “German-speaking region” in Central Europe is characterized by a large variety of regional food specialities and long tradition in craftsman's skills and experience in safe small-scale food processing and preservation. There is also increasing interest in these traditional products in other countries. Hence, this paper discusses the properties of characteristic food products, and outlines the steps critical for their safety. Such foods include fermented milk products (in particular cheeses), meat and fish products, fermented vegetables, and baked goods such as sourdough breads and spiced cookies. Data analysed show, among others, that (1) hard cheeses made from raw milk are regarded as safe, due to effective hurdles which eliminate foodborne pathogens during production and ripening, and semi-hard cheeses made from raw milk – which are generally ripened for more than 60 days – exhibit only a low health risk if Good Manufacturing Practice (including mastitis control) and effective HACCP systems (e.g. control of starter activity) are implemented; (2) Listeria monocytogenes is not a hazard specific to products from raw milk since it may grow on the surface of smear- and mold ripened cheeses after recontamination, and can be effectively controlled by monitoring systems including environmental samples; (3) semi-dry and dry sausages have a favourable record of safety whereas, in the manufacture of some undried, spreadable types, salmonellae (especially in pork sausages) and Shiga toxin-producing Escherichia coli (STEC; especially in sausages containing meat from ruminants) are frequently reduced only by one log cycle or less. Hence, the safety of these products critically depends on the quality of the raw material. This stresses the need of implementing Good Manufacturing Practice also in traditional processes.     

Irradiation: a critical control point in ensuring the microbiological safety of raw foods

The widespread and increasing incidence of foodborne diseases and the resultant social and economic impact on the human population have brought food safety to the forefront of public health concerns. This has prompted public health authorities worldwide to reassess their methods of food safety assurance, and to resort to a more cost-effective, preventive method that is known as hazard analysis and critical control point (HACCP). Ensuring food safety depends on effective control measures, i.e., methods to prevent food contamination and, when necessary, decontamination. Present production methods cannot totally prevent food contamination, and the complexity of food handling and processing provides ample opportunity for contamination as well as survival and growth of pathogenic organisms. It is also unlikely that the methods of production can ensure foods totally free from in the near future, for many pathogens are part of the normal flora of the environment. The application of an HACCP-based approach as a method for the management of hazards of the food chain demonstrates the need for applying a cold decontamination treatment as a control measure in the production of foods which are to be marketed raw or minimally processed. Irradiation (increasingly referred to as “cold pasteurization”) is such a control measure in the production of several types of raw or minimally processed foods such as poultry, meat and meat products, fish, seafood, and fruits and vegetables. In the production of these foodstuffs, irradiation may thus be a critical control point (CCP). It has the potential to eliminate vegetative forms of bacterial pathogens as well as parasites. Moreover, irradiation fulfils other criteria for a CCP, i.e., critical limits (minimum and maximum doses) can be established and monitored, and process control is well known. Corrective actions can also be taken when necessary. Irradiation is a safe technology and has been recognized as such by the FAO/WHO Codex Alimentarius Commission. It certainly merits the attention of industry and public health authorities. Today, 40 countries permit the irradiation of one or more foodstuffs: 12 countries have approved its use for pathogen control in poultry, 8 other for use in meats, and 13 in fish and seafood.     

Relevance and challenges in monitoring marine biotoxins in non-bivalve vectors

Seafood poisoning outbreaks can be caused by marine biotoxins which are naturally produced by harmful algal blooms. To minimize the risk of acute intoxications due to consumption of contaminated seafood a proper monitoring program must be in place. In recent decades several directives have been laid down by the European Commission to regulate known toxins, reassess their regulatory limits and update their reference detection methods. However, a revision of the seafood organisms that can act as toxin vectors has not been carried out. The control system has been designed based on physiological specificities of live bivalve mollusks. Although the prescribed controls in EC regulation 854/2004 apply to echinoderms, tunicates and marine gastropods, several difficulties are posed to a cost-effective monitoring program for these quite diverse and non-analogous groups of seafood organisms. Echinoderms, tunicates and marine gastropods are frequently secondary target species for toxins surveillance. In this study, the potential of non-bivalve organisms as toxin vectors and their threat for public health is evaluated based on their feeding behavior (i.e. filter-feeders, herbivores, predators), growth and metabolic rates, motile capacity and dynamics of toxin accumulation/elimination. A summary of previous reports on toxin accumulation and human incidents is presented to highlight the seafood species of higher risk to consumers, including crustaceans that are not listed in the EU directives for toxins monitoring and should be strongly considered as potent vectors of biotoxins to humans. Finally, the challenges in terms of sampling efforts and analytical determination for the regular surveillance of biotoxins in non-bivalve vectors are discussed.     

Risk identification in food safety: Strategy and outcomes of the EFSA emerging risks exchange network (EREN), 2010–2014

The European Food Safety Authority (EFSA) established an Emerging Risks Exchange Network (EREN) to exchange information between EFSA and the Member states (MSs) on possible emerging risks for food and feed safety in 2010. The Network is composed of delegates from MSs and Norway designated through the Advisory Forum of EFSA and observers from the European Commission, EU pre-accession countries, the Food and Drug Administration of the USA and the Food and Agricultural Organisation of the United Nations. Through 2010 to 2014, the EREN met 12 times. The EREN discussed a total of 63 signals of potential emerging issues that were presented and assessed using a standard template developed by the Emerging Risks unit of EFSA (EMRISK). Out of these signals, 39 originated from EFSA, 24 from MSs. The issues discussed were mainly microbiological and chemical hazards, but also food safety issues as result of illegal activity, new consumer consumption trends, biotoxins, new technologies and processes, allergens, animal health, environmental pollution, new analytical methods, new food packaging technology and unknown hazards were on the agenda. Based on the available evidence, EREN recommended whether an issue should be considered emerging or not, and if it merited further consideration, such as generating data on the issue, starting a full risk assessment and/or consultation of other bodies. According to the emerging risks identification process set in place at EFSA, the issues discussed and found of relevance by EREN were sent to the EFSA's Scientific Committee Standing Working Group on Emerging Risks for final evaluation. With four case studies, i.e the zoonotic potential of Usutu virus, risk of ciguatera fish poisoning in EU, zoonotic aspects of illegally imported wildlife products and benefits and risks of 3D food printing, the method developed to preliminary assess signals of potential emerging issues is presented and discussed.     

Detection of anisakids in fish and seafood products by real-time PCR

Anisakids are a group of widely distributed nematodes which have acquired high social relevance due to their involvement in foodborne infections caused by consumption of raw or undercooked seafood. A TaqMan^®-LNA probe real-time assay targeting the cytochrome oxidase subunit I (COI) was developed allowing the simultaneous detection of the most important anisakids species present in fish and seafood products.The determination of the detection limit in terms of ppm was 1 ppmFor the validation of method developed, twenty fish and cephalopod samples were experimentally contaminated with anisakid. It was checked that in cases in any anisakids species was present, it was detected because the Ct was always less than 35 and did not produce any case false negatives. The main novelty of this work lies in the fact that it can be applied to all kinds of processed products, including those undergoing intensive processes of transformation, as for instance canned foods. The proposed methodology is rapid, robust, highly sensitive and readily adaptable in routine molecular diagnostic laboratories, and can be employed as molecular screening method in order to assess the food security.     

HACCP development and regulatory assessment in the United States of America

Hazard Analysis Critical Control Point (HACCP) is internationally recognized as the best method of assuring product safety by controlling foodborne safety hazards. Currently, within the USA, the FDA has mandated HACCP for fish and fishery products and is proposing mandating HACCP for fruit and vegetable juices. The USDA has mandated Pathogen Reduction/HACCP requirements for meat and poultry processing, and the NMFS Seafood Inspection Program operates a voluntary HACCP program for seafood plants. The requirements for mandatory implementation and proposed regulations represent a significant change in the manner in which foods are regulated for food safety and necessitate a new understanding of the different roles and responsibilities between the food industries and the regulatory agencies within the USA. Each agency will approach the evaluation process differently given their unique legislative authorities and programmatic operations. Nevertheless, each agency agrees that HACCP is the best food control system of choice and is committed to improve food safety requirements.     

Virulence factors of Vibrio metschnikovii strains isolated from fish in Brazil

Vibrio metschnikovii is a natural inhabitant of the aquatic environment and has been isolated from seafood, and associated with disease in humans. This study presents results for virulence factors produced by V. metschnikovii strains isolated from fish. Results for virulence factors demonstrated that 38.5%, 92.3% and 100% of the strains were hemolytic on sheep, rabbit, and human blood agar, respectively. Verotoxin was produced by 100% of the strains tested and 76.9% were skin test positive. We concluded that potentially pathogenic Vibrio species, including V. metschnikovii, must be considered when investigating food borne diseases related to consumption of raw or undercooked seafood, mainly fish.     

Effectiveness and performance of HACCP-based programs

Since the early 1990’s, HACCP-based programs are being implemented as a means of preventing food hazards in fish and seafood products. From an engineering perspective, a system designed to control a manufacturing process is expected to result in final product that consistently meet requirements. Although audits are used to verify program implementation, there is a need for some product monitoring to measure the effectiveness and performance of the control systems. This paper discusses the need to monitor final product in seafood HACCP-based programs to measure effectiveness from a systems approach. Information time series of audits and inspections conducted are shown to be more indicative of program performance than snapshot inspections of the final product.     

The analysis of food safety incidents in South Korea, 1998–2016

This study uses media reports to analyze food safety incidents in South Korea that occurred between January 1998 and March 2016. The total number of incidents during this period was 975, with an average of 51.3 per year and 4.3 per month. The top five types of food involved were fruits and vegetables, fish and fish products, meat and meat products, beverages, and confectionery. Of the 975 incidents, 406 (41.6%) were related to chemical hazards—such as food additives and pesticides—221 (22.7%) were due to biological hazards, and 199 (20.4%) were due to physical hazards. Through analysis, this study determines at what stage a breakdown in food safety is likely to occur: primary production is the most common stage with 615 (63.1%) incidents, followed by incidents during the handling and distribution stages, at 240 (24.6%) and 65 (6.7%), respectively. The results of this study can be used as data for risk analysis or food safety strategies.     

Detection and identification of anisakids in seafood by fragment length polymorphism analysis and PCR–RFLP of ITS-1 region

Anisakids are a group of widely distributed nematodes which have acquired high social relevance due to their involvement in foodborne infections caused by consumption of raw or undercooked seafood. The current study has been focused on the development of a rapid and sensitive method for the detection of anisakids in seafood based on the polymerase chain reaction. The molecular marker studied has been the Internal Transcribed Spacer 1. The analytical strategy consists of two steps. The first step is based on specific primers and the length polymorphism of the amplified PCR product. This first probe allows detecting the presence of anisakids in fish, and in some cases determining the particular anisakid species. When the first step is not conclusive as to the exact anisakid species present in the sample, the restriction fragment length polymorphism analysis was carried out, allowing to assign the resulting profile to different anisakid species.The main novelty of this work lies is in the fact that it allows the simultaneous detection and identification of the most important anisakid species present in fish products. Also, two methodological alternatives were developed to adapt this method to different laboratories depending on the availability of equipment, one performed with simple instrumentation (agarose gels), and the other with more sophisticated instrumentation (Genetic Analyzer). Both can be applied to all kinds of processed products, including those undergoing intensive processes of transformation, as for instance canned foods. The proposed methodologies are rapid, robust, highly sensitive and readily adaptable in routine molecular diagnostic laboratories.     

Labelling accuracy in Tasmanian seafood: An investigation using DNA barcoding

Mislabelling of seafood products has been documented in numerous countries for over three-quarters of a century. With a trend towards increased consumption of seafood, the informed consumer demands accurately labelled products that provide full disclosure of composition. DNA barcoding can be used to accurately identify a seafood product to species based on its genetic signature, and so provides a means to test the authenticity and accuracy of seafood labelling. This can be especially useful for products such as fillets which have few or no unambiguous identifying characters, and can easily be mislabelled. We investigated labelling accuracy in seafood retailers in Tasmania, Australia. Thirty-eight seafood products were obtained from seafood retailers, sequenced for the barcoding gene region cytochrome oxidase subunit 1(CO1), and subsequently identified to species level by querying GenBank and Barcode of Life Data Systems (BOLD) DNA sequence records. Results were compared with standard fish names (SFN) prescribed under the Australian Fish Names Standard (AFNS) and FishBase. Of the 38 samples, none were deemed to have been mislabelled under Australian regulation, although in some cases naming discrepancies and ambiguity may cause confusion for some consumers. Our work, while reflecting high standards in Tasmanian seafood, highlights the need for mandatory standard labelling across all seafood products so as to eliminate any possible misrepresentation.     

Consumers’ perception toward quality and safety of fishery products,Beijing, China

Consumers around the world increased consumption of fish and fish products in recent years due to recognition of their nutritional value. Frequent occurrences of food safety scares heightened public awareness causing significant reduction in the consumption of the affected products. Many countries, including China, implemented a traceability system to increase vertical coordination and guarantee safety in fish products. This paper aims to provide information on consumers’ awareness to quality and safety of fish products, purchasing behavior, and willingness to pay (WTP) for safe fish products in Beijing, China, based on a survey of consumers. The results show a shortage of safety knowledge among customers concerning fish products, including processing, storage, and the traceability system. The age of consumers, educational level, the perception safety and the average price, are the main determinants of Beijing consumer’s WTP for the traceable products. On average, consumers are willing to pay a 6% premium for safe, traceable fish products over the price of non-traced products of uncertain safety.     

Detection and quantification of pathogenic Vibrio parahaemolyticus in shellfish by using multiplex PCR and loop-mediated isothermal amplification assay

Vibrio parahaemolyticus is a halophilic bacterium that commonly inhabits the marine and estuarine environments. This organism is also one of the leading causative pathogen of gastroenteritis often related to consumption of raw or undercooked seafood. In this study, molluscan shellfish (bloody clams and surf clams) and crustaceans (shrimps) were monitored in wet markets and hypermarkets. Two molecular methods were employed and compared to detect total and pathogenic V. parahaemolyticus in MPN enrichments: multiplex PCR and LAMP assay. The multiplex PCR was optimized to detect the total (toxR+), tdh+ and trh+ V. parahaemolyticus. On the other hand, the LAMP assay was employed to target the pathogenic strains only, the tdh+ and trh+, respectively. Out of 232 samples examined, 229 (98.7%) were positive for V. parahaemolyticus with counts ranging from 30 to >110, 000 MPN/g. Positive samples for tdh+ V. parahaemolyticus were obtained in 77 out of 232 (33.1%) samples ranging from 30 to >110, 000 MPN/g. Meanwhile, positive samples for trh+ were identified in 16 out of 232 (6.9%) samples examined ranging from 30 to 9600 MPN/g. Detection of samples with presence of tdh+ genes did not vary between methods, but a significant difference was observed when the LAMP assay was compared to PCR to detect trh+ V. parahaemolyticus. Therefore, on occasions where the density of the targeted genes is low, the LAMP assay serves as a better alternative. Nonetheless, this study constitutes an assessment of presence of total and potentially pathogenic V. parahaemolyticus in shellfishes for domestic consumption revealing the potential risk of contracting vibriosis if precautions and safety measures are not properly managed.     

Validation of real-time PCR for detection of six major pathogens in seafood products

Seafood can pose a public health concern to consumers. It is often consumed raw and may be contaminated with several foodborne pathogens. In order to guarantee the safety of seafood, real-time polymerase chain reaction (PCR) protocols may be used as these enable results to be provided within 24 h.The first goal of our work was to develop real-time PCR protocols enabling the detection of six foodborne pathogens that may be present in seafood products (Campylobacter jejuni, Campylobacter coli, enterohemorrhagic Escherichia coli, Salmonella spp., Vibrio parahaemolyticus, and Vibrio vulnificus). The corresponding gene targets were: 50S/VS1, rfbE, ttr, tlh, and vvp. A multiplex PCR was also developed to detect the virulence genes of V. parahaemolyticus: tdh and trh. A total of 420 bacterial strains belonging to four different genera/strains were used in this study. Sensitivity and specificity were always 100%, except in the case of Salmonella spp., where three strains were not detected by our PCR protocols.The second objective of our work was to assess the detection limit of our real-time PCR protocols on artificially contaminated seafood products (raw shrimps, cooked shrimps, and raw mussels), purchased in public stores. Six different levels of contamination were assayed in four replicates for each matrix. The real-time PCR protocols enabled a better level of detection than the ISO methods, except for Salmonella in raw shrimps and for V. vulnificus in shrimps (raw and cooked). The estimated level of detection was between 1 and 47 cfu/25 g sample for the ISO norms and between 1 and 315 cfu/25 g sample for the real-time PCR protocols tailored in our work.The real-time PCRs developed in our work allowed for good selectivity, sensitivity, and specificity. The sensitivity on seafood products was estimated at a level of 100%, except for Salmonella (97%). In the spiking assays, the levels of detection were lower with the real-time PCR protocol than those obtained with the ISO method. This was not the case for V. vulnificus in raw and cooked shrimps and for Salmonella in raw shrimps.These real-time PCR protocols appear to be good alternative methods for surveillance of seafood products to ensure the absence of foodborne pathogens.One additional conclusion is that laboratories have to use enrichment media that are compatible with those recommended by ISO standards. This may facilitate the isolation of the pathogen if the real-time PCR protocol gives a suspect positive signal during the first step of the seafood analysis.     

Seafood safety and quality: An analysis of the supply chain in the Sultanate of Oman

The globalization of trade in fish has created many challenges for the developing world specifically with regard to food safety and quality. International organisations have established a good basis for standards in international trade. Whilst these requirements are frequently embraced by the major importers (such as Japan, the EU and the USA), they often impose additional safety requirements and regularly identify batches which fail to meet their strict standards. Creating an effective national seafood control system which meets both the internal national needs as well the requirements for the export market can be challenging. Many countries adopt a dual system where seafood products for the major export markets are subject to tight control whilst the majority of the products (whether for the local market or for more regional trade) are less tightly controlled. With regional liberalization also occurring, deciding on appropriate controls is complex. In the Sultanate of Oman, fisheries production is one of the countries' chief sources of economic revenue after oil production and is a major source of the national food supply. In this paper the structure of the fish supply chain has been analysed and highlighted the different routes operating for the different markets. Although much of the fish are consumed within Oman, there is a major export trade to the local regional markets. Much smaller quantities meet the more stringent standards imposed by the major importing countries and exports to these are limited. The paper has considered the development of the Omani fish control system including the key legislative documents and the administrative structures that have been developed. Establishing modern controls which satisfy the demands of the major importers is possible but places additional costs on businesses. Enhanced controls such as HACCP and other management standards are required but can be difficult to justify when alternative markets do not specify these. These enhanced controls do however provide additional consumer protection and can bring benefits to local consumers. The Omani government is attempting to upgrade the system of controls and has made tremendous progress toward the implementation of HACCP and introducing enhanced management systems into its industrial sector. The existence of strengthened legislative and government support, including subsidies, has encouraged some businesses to implement HACCP. The current control systems have been reviewed and an SWOT analysis approach used to identify key factors for their future development. The study shows that seafood products in the supply chain are often exposed to lengthy handling and distribution process before reaching the consumers, a typical issue faced by many developing countries. As seafood products are often perishable, they safety is compromised if not adequately controlled. The enforcement of current food safety laws in the Sultanate of Oman is shared across various government agencies. Consequently, there is a need to harmonize all regulatory requirements, enhancing the domestic food protection and to continue to work towards a fully risk-based approach in order to compete successfully in the global market.     

Occurrence and antibiotic resistance profiles of Listeria monocytogenes isolated from seafood products and market and processing environments in Iran

This study was designed to determine the occurrence of Listeria monocytogenes in popular seafood products and their market and processing environments. The frequency of L. monocytogenes contamination was found to be 4.83% in raw and 14.5% in RTE seafood products. In raw products, the prevalence of L. monocytogenes was significantly higher (P < 0.05) in freshwater fish (11.4%) than in seawater fish (1.80%) and shrimp (1.69%). Cold-smoked fish had the highest frequency of L. monocytogenes contamination among the RTE products. The microbial load of L. monocytogenes in seafood products was in the range of <0.3 to 1100 MPN/g; and did not exceed 100 MPN/g in most of the examined samples. The incidence of L. monocytogenes in environmental and personnel samples was 17.1% and 16.2% in markets, and 21.3% and 18.2% in processing plants, respectively. It was found that contamination of processed fish fillets and shrimp flesh with L. monocytogenes mainly originated from the processing environments, rather than the raw materials. In addition, the implemented cleaning procedures were insufficient to eliminate L. monocytogenes from the market and processing environments. Serological examinations revealed that serotype 1/2a (45.7%) was the predominant serotype of L. monocytogenes followed by 4b (40.3%), 1/2c (5.39%), 1/2b (4.68%), and 4c (3.96%). Regarding seasonal variability, 1/2a was the dominant serotype during warm seasons, whereas 4b was the most prevalent serotype during cold seasons. The isolates of L. monocytogenes were highly resistant to penicillin, ampicillin, tetracycline, and vancomycin. The results indicate that prevalence of L. monocytogenes serotypes 1/2a and 4b, which are associated with foodborne outbreaks of human listeriosis; and their resistance to commonly used antibiotics for treatment of human listeriosis could be a public health concern.     

DNA barcoding reveals a high level of mislabeling in Egyptian fish fillets

Accurate identification of seafood species in the markets is a growing concern due to the high incidence of species substitution at international level. It is a prime priority for governments to be able to identify the already processed fish products (fish fillets). In this context, DNA barcoding was applied to ascertaining species in fish fillets (tilapia, Nile perch and panga) purchased from Egyptian markets. Ninety commercial samples were analyzed. Sequencing of a short fragment of mitochondrial cytochrome oxidase I (COI) gene revealed 33.3% species substitution in the fish fillets analyzed, 50% Nile perch (Lates niloticus) and 50% basa fish (Pangasius bocourti) being replaced by imported Vietnamese tra fish (Pangasianodon hypophthalmus). These results demonstrate that DNA barcoding is a reliable tool for detecting fish products adulteration in Egypt. We recommend its use for control and law enforcement of seafood quality.     

DNA barcoding reveals substitution of Sablefish (Anoplopoma fimbria) with Patagonian and Antarctic Toothfish (Dissostichus eleginoides and Dissostichus mawsoni) in online market in China: How mislabeling opens door to IUU fishing

China’s rapid economic development has determined profound changes in seafood consumption patterns, and nowadays besides the traditional luxury seafood, high-quality marine fish are consumed. Among these is Anoplopoma fimbria (Sablefish), a highly priced species on the Chinese market. A recent molecular survey on products sold online in China found that all the analyzed products sold as Yin Xue, used to indicate A. fimbria, were instead Dissostichus spp., a genus of fish extremely vulnerable to overfishing (Xiong et al., 2016). Considering this and the lack of a standardized naming system for seafood species in China, an initial search was conducted to identify all the possible Chinese names indicating A. fimbria. The aim of the present study was to assess the challenges of the online market with regards to frauds for fish species substitution. DNA barcoding was employed to verify the identity of 42 products sold on e-commerce platforms as Sablefish. Moreover, the information reported on the webpage and on the label was analyzed according to the Chinese regulation in force. All the PCR products gave readable sequences. By using the IDs analysis on BOLD and the BLAST analysis on GenBank all the samples were unambiguously identified at the species level. Of the 42 products sold as Sablefish, only 6 (14.3%) were molecularly identified as this species, while 32 (76.2%) were identified as Dissostichus eleginoides (Patagonian Toothfish) and 4 (9.5%) as Dissostichus mawsoni (Antarctic Toothfish), highlighting an alarming overall misrepresentation rate of 85.7% and implications for the management of these species’ fisheries. The combined analysis of all the information of the webpages and the labels allowed us to hypothesize unintentional and intentional mislabeling. Our findings suggest the possible existence of a trade pattern enabling IUU fishing operators to launder illegal catches of Toothfish through mislabeling.     

Control of biological hazards in cold smoked salmon production

An outline of the common processing technology for cold smoked salmon in Denmark is presented. The safety hazards related to pathogenic bacteria, parasites and biogenic amines are discussed with special emphasis on hazards related to Clostridium botulinum and Listeria monocytogenes. Critical control points are identified for all hazards except growth of L. monocytogenes. For this reason a limitation of shelf life to three weeks at + 5 °C for cold smoked vacuum-packed salmon having ≥3% water phase salt is recommended.