Biogenic amines are compounds that play several crucial roles in the human body but can also cause serious health problems when present at high concentrations in foodstuffs. Therefore, it is important to develop rapid, simple, cost-effective, and reliable analytical techniques for their monitoring, acting as indicators of food quality and preventing potential risks. In this sense, carbon dots and 3-mercaptopropionic acid (MPA)-capped AgInS2 (AIS) quantum dots were used as fluorescent probes to implement a ratiometric sensing platform, coupled to chemometrics, for the kinetic fluorometric determination of histamine in foodstuffs using second-order data. The obtained data were analysed through unfolded partial least squares (U-PLS) and N-way partial least squares (N-PLS). The model optimization revealed that the application of N-PLS yielded the best results and that a kinetic spectral acquisition for 5 min was enough to ensure reliable measurements. The developed method was evaluated using spiked samples of different complex matrices (tuna, tomato and hake fish), at different concentration levels, and the obtained results, in terms of figures of merit, confirmed its suitability, accuracy and effectiveness. In fact, a relative percentage error below 10%, with a coefficient of determination for the prediction higher than 0.9, was obtained, together with a LOD and LOQ of 1.26 and 3.80 mg L−1, respectively, which are much lower than the maximum threshold value established by European Union legislation for histamine in fishery products (200 mg kg−1). These results were obtained with samples containing uncalibrated species and without using toxic reagents, which attest the suitability of the procedure. Globally, the developed methodology proved to be accurate and much simpler and faster than the reference procedures.

This study was performed to screen and select biogenic amine (BA)-degrading Bacillus strains originating from Cheonggukjang and to examine the practical effects of the Bacillus strains on BA reduction during Cheonggukjang fermentation in the presence or absence of Enterococcus faecium known to be the principal species of tyramine production. Out of a total of 327 strains isolated, three BA-degrading and low BA-producing strains were selected through in vitro tests and were identified as B. licheniformis CH7P22, B. haynesii CH7P24, and B. velezensis CH7P28. The selected strains were used for the fermentation of Cheonggukjang with or without E. faecium inoculation. During fermentation, the sample inoculated with B. licheniformis CH7P22 showed the largest reduction in tyramine (43.25–91.50%) and spermine contents (40.35–69.93%) compared to the negative controls (samples inoculated with non-BA-producing Bacillus strains) and positive control (sample inoculated with a prolific tyramine-producing Bacillus strain). This sample also showed the largest reduction in histamine content (100.00%) compared to the blank sample (sample prepared without an inoculum). In the fermentation of Cheonggukjang in which a prolific tyramine-producing strain of E. faecium was inoculated, the sample inoculated with B. licheniformis CH7P22 exhibited a reduction in tyramine content (17.02–63.26%) compared to the controls, as well as in histamine (100%) and spermine content (59.32%) compared to the blank sample. The findings of this study indicate that B. licheniformis CH7P22 could be applied to Cheonggukjang as a starter and/or protective culture to reduce food safety risks associated with BAs, regardless of Enterococcus contamination.

Fresh trout (Oncorhynchus mykiss) is a healthy and nutritious food which can be used for formulating ready-to-cook fish preparations, such as trout burgers. To investigate the impact of processing and the use of an acetate-based preservative on the spoilage microbiota and storage life of burgers, the dynamics of microbial communities were examined by using a combination of culture-dependent/independent techniques, Monte Carlo simulation, and PICRUSt2 analysis. Results of the microbial community analyses showed that most of the taxa of trout were lost during processing into burgers. Along the processing steps, an increase of contamination, with Flavobacterium and Pseudomonas becoming the most relative abundant genera in pulp and burgers, respectively, was observed. The Pseudomonas dynamic pattern was supported by the Monte Carlo simulation, which gave a picture of the bacterial transfer. Verdad® N6, which is a commercially available acetate-rich fermentate, was evaluated as preservative treatment for burgers during their storage life. Pseudomonas dominated the microbial community of stored burgers, irrespective of the treatment. However, their levels were lower in the fermentate-treated samples, which presented Lactobacillus as the second most relative abundant genus. PICRUSt2 analysis showed that Pseudomonas-correlated metabolic pathways of hexitol fermentation were significantly lower at the end of the storage period in burgers supplemented with the fermentate, corroborating Pseudomonas minor contribution to the metabolic activity. In summary, Verdad® N6, through its inhibiting effects on spoilage bacteria is an option for producing burgers with increased storage life.

Lactic acid-injured foodborne pathogens and spoilage bacteria may regain their full viability when transferred to favorable environments, posing a potential threat to human health or foods. However, such bacteria fail to form colonies on selective media and consequently evade detection, resulting in the underestimation of detected bacterium on one hand. Meanwhile, viable cells or even some early-recovered cells may multiply before ∼100% recovery of the lactic acid-induced sublethal injuries, leading to the overestimation of detected organisms on the other hand. To address this dilemma, here we developed a completely novel Escherichia coli-repair broth (ERB) containing (w/v): 15% of the pH-neutralized lysis from Spirulina platensis after 36 h proteolytic action by the secretory enzymes of Bacillus subtilis, potassium phosphate (0.04 M, pH 8.0), 1% glucose and 0.5% Tween 80. We showed that ERB rapidly repaired ∼100% of lactic acid-induced E. coli K-12 and O157:H7 in 20 min, whereas trypticase soy broth, the best repair broth currently, only repaired ∼37.68% and ∼38.74% respectively. More importantly, no apparent multiplication occurred in ERB amid the recovery. Taken together, ERB has a prominent ability to precisely enumerate all harmful (sublethally injured plus uninjured) E. coli. We hope that ERB will become the first choice in microbiological analysis of E. coli for food safety in the future.

Fish gelatin films containing lauroyl arginate ethyl (LAE) at different loading amount (0.5, 1, 1.5 and 2%, w/w) were successfully fabricated by electrospinning. Fourier transform infrared spectroscopy results indicated that LAE was encapsulated in electrospun fish gelatin films, and there was hydrogen bond between LAE and fish gelatin. Scanning electron microscopy observation demonstrated that the electrospun fibers were uniform and the fiber diameters ranged from 164 to 193 nm. Meanwhile, thermogravimetric analysis showed that all the electrospun films exhibited high thermal stability. It was observed that the LAE loaded films had good antibacterial activity against Staphylococcus aureus and Escherichia coli. Furthermore, the effect of LAE (2%, w/w) loaded electrospun films on fish preservation was investigated by comparing with other packaging methods. The electrospun fish gelatin films could absorb water on the surface of fish fillets and transform into hydrogel coating. Results suggest that the LAE loaded hydrogel coating could delay decay of large yellow croaker (Pseudosciaena crocea) fillets and extend the refrigerated shelf life by about three days. In conclusion, the electrospun fish gelatin films containing LAE have potential use for antibacterial food packaging.

Digital technologies offer unprecedented opportunities to modernize official food safety control. Shift from paper- to digital-based systems enable recording and reporting data directly in digital format and further analyze and disclose inspection data. Further to this, digital technologies enable the automatization of processes through rule-based instructions, a fact that could positively influence the consistency of official control. Nevertheless, the extent of the use of digital technologies during official food safety control inspections by competent authorities (CAs) of European Union (EU) countries is not known. For this reason, the aim of this study was to assess the level of use of a digital environment during inspections at retail establishments. This was performed by administering a questionnaire to CAs from EU countries. A total of 88 national, regional or local CAs from 15 EU countries responded to the questionnaire. Of them, 62.5% (55/88) used a digital environment during inspections, the majority to standardize data collection and reporting. CAs autotomize processes through digital technologies related to the management of official control and generation of inspection results, but to a lesser extent to automatize decision-making during inspections. Of the CAs not using a digital environment (37.5%; 33/88), technological constraints and lack of economic resources were the two most prevalent reasons for not using such an environment. The use of digital technologies as decision support tools to standardize official controls and improve consistency and efficiency should be enhanced for the benefit of society.

Increasing the stringency of microbiological criteria is a risk management measure that can improve food safety and hygiene, but its adoption by governments around the globe is limited. In 2018, a hygiene criterion for Campylobacter in broilers was originally set by the European Commission, which intended to progressively increase its stringency in 2020 and in 2025. In this study, the effects of this regulation on the level of (non-)compliance were estimated based on baseline data on Campylobacter for the different European Union (EU) Member States and associated countries in 2008. Qualitative and quantitative baseline data were used to estimate concentration distributions, from which the levels of compliance with the legal limits were determined, making use of the ICMSF sampling plan spreadsheet and considering different batch properties (i.e., standard distributions of microorganism) and different non-compliance detection probability values. Based on the 2008 baseline data, the performance of the criterion is estimated to target the reduction of the mean log contamination level to about 0.25 and 0.5 log (factor 2 and 3 in arithmetic concentration) and to about 0.5 and 1.1 log (factor 4 and 12 in arithmetic concentration) in case the c-value decreases from 20 to 15 and from 20 to 10, respectively. Assuming a compliance level in practice of at least 98%, more and more food business operators in EU Member States would fail to meet this level as a consequence of the increasingly stringent criterion. This analysis clearly shows that a timewise push to further improve hygiene standards will be needed in various countries for their food businesses to be able to achieve a high level of compliance with the progressively stringent EU Campylobacter process hygiene criterion.

Radio frequency (RF) has found its potential in ensuring the safety of packaged powdered infant formula milk (PIFM). PIFM was processed by RF at different temperature-holding time treatments (70ºC-115 min, 75ºC-50 min, 80ºC-25 min, 85ºC-10 min, and 90ºC-5 min) to obtain 5-log reduction of Cronobacter sakazakii, and its physicochemical characteristics were investigated. Various RF treatments possessed insignificant effects on color difference (ΔE 99%), crystallinity (∼5%), surface chemical composition (>30% fat, 15%–20% protein, and 45%–50% lactose), and microstructure of PIFM. Lower temperature-longer holding time treatment as 70ºC-115 min caused 51% reduction in water activity and 71% reduction in moisture content, thereby considerably increasing the glass transition temperature of PIFM from 60.3 °C to 78.4 °C. Protein secondary structures were preserved; however, 75ºC-50 min and 80ºC-25 min treatments significantly (P < 0.05) decreased the α-helix structure. All RF heating conditions significantly (P < 0.05) altered the concentration of volatile organic compounds in PIFM and increased the relative abundance of lipid oxidation substances such as (E)-2-heptenal, 2-heptanone, and n-nonanal. PIFM can be treated at 90 °C for 5 min for better quality and processing efficiency.

Population growth, international market expansion, and climate change have caused changes in agricultural practices, including increased use of phytosanitary products to control pests and diseases in food production. The European Union aims to achieve sustainable and high-quality food, with the priority of reducing pesticide use. Determining the content of these substances in food is crucial to ensure consumers are not excessively exposed to them. Based on that, in this study, 174 pesticides, including acaricides, fungicides, herbicides, insecticides, nematicides, plant growth regulators, among others, were analysed in 152 wine samples commercialised in the Canary Islands (111 white wine and 41 red wine samples) between 2017 and 2019, including local wines and imported from other locations of Spain. For this purpose, the QuEChERS method combined with liquid chromatography and gas chromatography-tandem mass spectrometry were used. The methodology was successfully validated in terms linearity (R2 ≥ 0.9901), trueness (recovery of 46–133%), precision (relative standard deviation < 20%) and sensitivity (complies with maximum residue limits). A wide variety of pesticides were found, highlighting the presence of fungicides as expected, since these substances are widely used in the treatment of wine grapes against fungi diseases. Likewise, a low rate of exceedances of the maximum residue levels was found. Finally, a non-cumulative toxicological study was carried out based on the Margin of Safety Approach, using a conservative screening. Results shown maximum values of 7.4% of the health-based guidance values, indicating that the consumption of Spanish wines marketed in the Canary Islands is safe in the short and long term.

Biogenic amines are naturally present as hazardous, low-molecular organic basic compounds in various foods. Lactic acid bacteria show excellent potential to prevent biogenic amines accumulation. In this study, the amine-reducing mechanism of Lactiplantibacillus planatraum JB1, a strain isolated from fermented sausages, was explored according to its genome, and its ability to degrade biogenic amines was also evaluated in culture medium and dry sausage. The results showed that L. plantarum JB1 possessed a myriad of desirable properties, including tolerance to harsh environments and safety for assessment in vitro. Its genome contained genes encoding transport proteins and multicopper oxidase, which may be involved in biogenic amine degradation. In PBS and MRS medium, L. plantarum JB1 could degrade eight biogenic amines with high degradation rates for tyramine and putrescine. By inoculating sausages with L. plantarum JB1, the total content of biogenic amine was decreased by 32.84% after preparation and 32.07% after storage. Due to its good adaptability, security and amine-reducing capacity, L. plantarum JB1 could be considered a starter culture to ensure the safety of meat products.

The growing concern and demand for food safety in society dictate the necessity of developing intelligent portable devices for monitoring the whole food process from production to table. The development of flexible printed electronics provides one of the most promising paths for this challenge, as this technology brings together the unique advantages of various important technologies. Today, various specific products based on flexible printed electronics have been successfully developed, such as flexible printed sensors and radio frequency identification systems, which are excitingly able to meet various requirements for food safety, including ingredient detection, environmental monitoring, logistics tracking, and anti-counterfeiting and anti-theft. However, the current flexible printed electronics technology is still not mature enough. This review comprehensively introduces the different kinds of flexible substrates, printable conductive materials, and printing technologies involved in flexible printed electronics technology with their respective advantages and limitations, and then focuses on the application of flexible printed electronics technology in food quality monitoring and intelligent food packaging in recent years, intending to provide the latest reference for the development of intelligent food safety control.

The COVID-19 pandemic reshaped every aspect of life, including food safety. Understanding food safety behaviour at home is necessary for developing effective strategies to mitigate foodborne disease during and after this pandemic. This study administered a cross-sectional survey among 503 domestic food handlers to examine the food handlers’ food safety concerns during the pandemic and pandemic-related knowledge and hygiene behaviour (PRKHB) in Bangladesh. The results found that only 35.8% of respondents in this study were more concerned about food safety because of the COVID-19 pandemic. Although the results found a good PRKHB among 95.8% of urban food handlers, overall, 62% showed a poor level of PRKHB. Only 38.8% reported washing their hands after returning home or preparing meals every time. The regression model found that food safety concerns positively related to the PRKHB, and participants who lived in rural areas had a negative association with the PRKHB. The study also explored sociodemographic variations and significant differences observed between urban and rural areas. Meticulous educational campaigns and targeted messages to the food handlers on food safety risks, food handling practices and hand hygiene are necessary to minimise the foodborne disease burden in this region.

Lipid oxidation is the main cause of meat deterioration. Hyperspectral imaging (HSI) technique has attracted attention as a non-destructive testing method. However, the complexity and overlap of the pork hyperspectral data lead to difficult band interpretation and computational overload. In this paper, a lightweight three-dimensional convolutional neural network (3D-CNN) model combined with two-dimensional correlation spectroscopy (2D-COS) analysis was proposed to monitor the lipid oxidation of frozen pork. Through the generalized 2D-COS analysis, the band interpretation of visible near-infrared (vis-NIR) HSI was established and the sequence of event changes caused by pork deterioration was monitored. It was found that sulfmyoglobin and oxymyoglobin were prone to change, and the decomposition of sulfmyoglobin and metmyoglobin occurred before the formation of oxymyoglobin. Moreover, the hetero 2D-COS analysis was used for the first time to correlate vis-NIR with fluorescence spectra to analyze more feature bands of vis-NIR HSI. A lightweight 3D-CNN regression model was developed for hyperspectral images of feature bands to quantitatively predict TBARS. It was found that 10 feature bands were obtained by integrating bands identified by generalized and hetero 2D-COS. The 3D-CNN model of these feature bands has yielded good results in predicting TBARS with R2p of 0.9214 and RMSEP of 0.0364 mg kg−1. Overall, this study provided a method for band assignment and interpretation of vis-NIR HSI and an end-to-end new approach for rapid and non-destructive monitoring of pork oxidative damage.

Flexible sensing technology for food quality control has received some attention in recent years. The aim of this research was to develop a novel flexible sensor to assess the freshness of lamb meat, replacing the traditional rigid sensor and lamb quality indicator testing method. Firstly, a low-cost, high-performance flexible impedance-temperature electrode was prepared based on laser direct writing technology, and a complete flexible temperature-impedance measurement system was built in combination with an STM32 microcontroller. Then, a wireless sensor network (WSN) based micro-environment monitoring platform was developed to measure the quality index of lamb, collect gas information, and impedance information under three temperatures of 0 °C, 4 °C, and 8 °C. As the storage time of lamb increases, its biological tissue structure and intracellular ionic conductive properties change, which can be reflected by the impedance amplitude and phase angle. A machine learning prediction model is established with bio-impedance as the input and freshness as the output. The research found that the variation of lamb freshness was influenced by the storage temperature, and that the impedance mode of the flexible system was able to instantly detect the freshness of lamb with an average prediction accuracy of 91.63% when combined with machine learning algorithms. This is higher than the accuracy of the traditional Arrhenius equation method (83.70%) and comparable to the prediction accuracy of gas information (93.24%). Additionally, the temperature mode of the flexible system was able to continuously monitor temperature changes on the surface of lamb, compensating for the inability of traditional impedance sensors to do so, and providing unique insights into accurate monitoring of lamb temperature changes. This research provides a new solution for improving food quality control during the chilled meat cold chain.

Bivalve molluscs have for many years been used as indicator organisms for environmental pollution with various chemical substances. However, limited information is available on the levels of chemical contaminants in mussels and oysters intended for human consumption. Polycyclic aromatic hydrocarbons (PAHs) and toxic metals, such as cadmium (Cd), mercury (Hg) and lead (Pb) have been analysed in edible bivalve samples and the present study provides the results from samples collected in Danish waters from 2005 to 2019. Principal Component Analysis (PCA) and Pattern Recognition Neural Network (PRNN) analysis were applied to data to identify any differences according to organism, locality, and contaminant levels. Differences were confirmed for Pb concentrations being generally higher in mussels than oysters. Based on toxic metals results, the PCA and PRNN analyses made it possible to categorise samples as a mussel or an oyster, as well as make decisions on the origin of a specific sample. All concentrations in mussels and oysters were below the current European Union maximum levels for the contaminants.

Tetracycline (TC) is an essential class of wide-spectrum antibiotics with one of the highest applications (e.g., bacterial infectious diseases and growth-promoting additives). However, TC can cause antibiotic resistance, allergic reactions, and other adverse effects in non-target organisms. Because of its recalcitrant nature, foods and water might be contaminated with trace quantities of TC. Owing to the complexity of food samples, the construction of selective and sensitive TC sensors has attracted considerable attention. Therefore, the focus of this review article is on the application of metal-organic frameworks (MOFs) for detecting TCs in food and water samples. Different detection methods of MOF-based TC sensors (e.g. optical, electrochemical, or colorimetric) are discussed. In addition, the approaches to enhance the sensor performance of MOF-based TC sensors (e.g., incorporation with other functional materials) is discussed. In the final section, the limitations of MOFs for the development of TC sensors and future prospects are discussed to help researchers of various realms develop effective and sensitive MOF-based TC sensors.

Fatty acids are a key index for measuring wheat storage quality. This study provides a quantitative method for determining fatty acids in stored wheat using an olfactory sensor technique. A 4 × 3 olfactory sensor array was prepared using 12 chemical dyes (porphyrins) to collect volatile odor information from stored wheat. A dung beetle optimizer (DBO) algorithm was used to determine the best characteristic color variable combination for the olfactory sensor, and a wheat fatty acid value detection model based on support vector regression (SVR) was established. The results showed that the DBO algorithm can effectively screen out characteristic color variables that are closely related to the wheat fatty acid value. The SVR detection model built on the 11 characteristic color variables selected by the DBO algorithm exhibited the best performance. The root mean square error of prediction was 3.0384 mg/100 g, and the coefficient of correlation (RP) was 0.9413. These results demonstrate that the olfactory sensor prepared by our team has a promising application potential in the quality inspection of stored grains.

One of the major hazards in cured meat is the ochratoxin A (OTA) accumulation, being the main producer Penicillum nordicum. Plant extracts can be used as biopreservative agents to its minimisation. The aim of this work was to evaluate the activity of essential oils from rosemary (REO), thyme (TEO) and oregano (OEO), and an acorn extract (AE) against three P. nordicum strains by analysing their inhibitory capacity on their growth and OTA biosynthesis in a dry-cured sausage-based agar. When evaluating their effect on the mould growth, the essential oils showed different antifungal activity, being concentration dependent. Concretely, the TEO and OEO activity was greater than that of REO, with a loss of activity throughout the incubation. As incubation time progressed, the plant extract ability to reduce the OTA content decreased. Additionally, differences at strain level were noticed depending on the plant extract, since some of them were able to trigger an overproduction of OTA. REO 500 μL/mL and OEO 50 μL/mL reduced the OTA production up to 93 and 98%, respectively, showing the best outcomes to be further explored as effective strategy to control the presence of OTA due to P. nordicum in dry-cured sausages.

Fresh root vegetables are one of the main causes of viral foodborne diseases; however, the associated risk has not been fully considered. Therefore, the prevalence of five foodborne viruses including norovirus (NoV), hepatitis A virus (HAV), rotavirus (RotaV), adenovirus (AdV), and astrovirus (AstroV) in pre- and post-washed root vegetables (potato, carrot, sweet potato, and radish) were investigated by RT-qPCR or qPCR, nested RT-PCR, and sequencing. AdV and NoV GII were only detected in pre-washed samples. NoV GII was found in 1% and 2% of the potatoes and carrots, respectively and AdV in 4% and 10% of the potatoes and radishes, respectively. HAV was detected in 5.8% and 1.3% of the pre-and post-washed sweet potatoes, respectively and in 8% and 2% of the post-washed carrots and radishes, respectively. NoV GI and AstroV was not detected in any of the root vegetables. Sequencing and phylogenetic analysis revealed that the genotypes of AdV, NoV, and HAV were belonged to human AdV 41, NoV GII.3, and HAV IA and IB, respectively. This molecular surveillance study clearly demonstrated that human pathogenic viruses are found in root vegetables, and it is possible that they may serve as a potential reservoir for such viruses. Therefore, further research is necessary to confirm this hypothesis. Nevertheless, washing produce can lower the risks of contracting diseases due to certain root vegetables.

A novel fluorescent immunochromatographic assay (ICA) with excellent specificity and sensitivity for evaluating trace residues of zearalenone (ZEN) in cereal samples was successfully developed. La3+-doped upconversion nanoparticles (UCNPs) were assessed as antibody labels, following optimization of doping ratios. Our results indicated that 20% La3+-doped UCNPs had superior morphological structure and fluorescence characteristics, making them the optimal UCNPs. After labeling 20% La3+-doped UCNPs with ZEN monoclonal antibodies (mAbs), optimal polyacrylic acid amount, coupled mAbs amount, detection time, and fluorescent immunoprobe concentrations were determined as 2.0 mL, 20 μg, 10 min, and 8 mg/mL, respectively. Under optimized detection conditions, the limit of detection (LOD) for ZEN standard solutions was 0.25 ng/mL with coefficients of variation (CVs) ＜ 8.67% and a high linear correlation (R2 = 0.9944). Furthermore, specificity analysis demonstrated that prepared test strips were highly specific for the target mycotoxin. The LODs of ZEN in wheat and maize were both 0.5 μg/kg in spiking recovery experiments, and the recoveries were 87.65%–99.26% and 84.12%–95.12% with the CVs being 1.29%–7.14% and 4.03%–9.01%, respectively, confirming that the optimal UCNPs-ICA was efficient, straightforward, and suitable for rapid on-site screening of ZEN in cereals.