Direct and indirect contamination with ochratoxin A of ripened pork products

An overview of fermentation in the food industry - looking back from a new perspective

Fermentation is thought to be born in the Fertile Crescent, and since then, almost every culture has integrated fermented foods into their dietary habits. Originally used to preserve foods, fermentation is now applied to improve their physicochemical, sensory, nutritional, and safety attributes. Fermented dairy, alcoholic beverages like wine and beer, fermented vegetables, fruits, and meats are all highly valuable due to their increased storage stability, reduced risk of food poisoning, and enhanced flavor. Over the years, scientific research has associated the consumption of fermented products with improved health status. The fermentation process helps to break down compounds into more easily digestible forms. It also helps to reduce the amount of toxins and pathogens in food. Additionally, fermented foods contain probiotics, which are beneficial bacteria that help the body to digest food and absorb nutrients. In today's world, non-communicable diseases such as cardiovascular disease, type 2 diabetes, cancer, and allergies have increased. In this regard, scientific investigations have demonstrated that shifting to a diet that contains fermented foods can reduce the risk of non-communicable diseases. Moreover, in the last decade, there has been a growing interest in fermentation technology to valorize food waste into valuable by-products. Fermentation of various food wastes has resulted in the successful production of valuable by-products, including enzymes, pigments, and biofuels.

Traditional Meat Products-A Mycotoxicological Review

Traditional meat products are commonly produced in small family businesses. However, big industries are also involved in the production of this kind of product, especially since a growing number of consumers crave the traditional taste and aromas. The popularization of original and organic products has resulted in a return to traditional production methods. Traditional meat products are produced worldwide. However, in such (domesticated) conditions there is a potential danger for mycotoxin contamination. This review aims to present the sources of mycotoxins in traditional meat products, the most common mycotoxins related to such meat products, and future prospects regarding the suppression of their occurrence. Special attention should be paid to reducing the transfer of mycotoxins via the food chain from animal feed to animals to humans (stable-to-table principle), which is also described in this review. Other sources of mycotoxins (spices, environment, etc.) should also be monitored for mycotoxins in traditional production. The importance of monitoring and regulating mycotoxins in meat products, especially in traditional meat products, is slowly being recognized by the institutions and hopefully, in the future, can deliver legally regulated limits for such products. This is especially important since meat products are available to the general population and can seriously affect human health.

The prevalence and concentration of ochratoxin A in meat and edible offal: A global systematic review and meta-analysis

The prevalence of ochratoxin A (OTA) in meat, edible offal, and meat products (MOP) was assessed through systematic review and meta-analysis. Four electronic databases were used to gather data from 1975 to September 15, 2022. Seventy-five articles comprising 8585 samples were identified and analyzed. The studies included in the analysis were conducted at a global level, with a predominant focus on Europe [72% (54/75)], Asia [13.33% (10/75)], Africa [13.33% (10/75)], and North America [1.33% (1/75)]. The overall prevalence of OTA in MOP was 39%. The highest and lowest prevalence percentages were recorded in Iraq (77%) and the USA (3%), respectively. Concerning food type, OTA prevalence was highest in the poultry gizzard (66%) and lowest in the cow liver (2%). The overall concentration of OTA in the MOP was 1.789 μg/kg. Poultry kidneys had the highest concentration of OTA (0.880-22.984 μg/kg), while pork had the lowest concentration (0.127-0.824 μg/kg). Conspicuous amounts of OTA contamination have been reported in fermented sausages. The lowest OTA concentration was found in Belgium (0.220 μg/kg) and the highest in Denmark (60.527μg/kg). These results can help food authorities minimize and control OTA in the MOP.

Ochratoxin A in Dry-Cured Ham: OTA-Producing Fungi, Prevalence, Detection Methods, and Biocontrol Strategies-A Review

Traditional dry-cured hams are easily contaminated by toxigenic fungi during the fermentation and ripening stages. The detection and positive rates of ochratoxin A (OTA) are the highest among mycotoxins detected in traditional dry-cured hams, indicating that OTA in hams is a potential safety hazard to human health. This review addresses the mycotoxin-producing fungal species, the toxigenic conditions causing OTA contamination worldwide, the prevalence of OTA contamination in dry-cured hams, and the detection methods applied in OTA analysis. Additionally, this study introduces methods to prevent and control OTA in traditional dry-cured hams. The growth of common mycotoxin-producing fungi and the accumulation of mycotoxins in dry-cured ham can be controlled by a microbial starter. This review provides an important theoretical foundation for the research and control of OTA in traditional dry-cured hams.

Investigation of ochratoxin A in commercial cheeses and pork meat products by liquid chromatography-tandem mass spectrometry

Ochratoxin A (OTA) is a mycotoxin produced by several species of Aspergillus and Penicillium and commonly detected in a wide range of foodstuffs. The purpose of this work was to monitor the presence of OTA in cheeses and pork meat products. A simple and accurate "dilute and shoot" method with no need of immunoaffinity column and isotopic labeled internal standard, by liquid chromatography-tandem mass spectrometry, was validated in accordance with the criteria set out in Commission Regulation (EC) No. 401/2006. The method showed good linearity in solvent and in matrix (R²  ≥ 0.995), limit of detection was 0.2 µg/kg for cheese and 0.3 µg/kg for pork meat products, limit of quantification was fixed at 1 µg/kg, and recovery was estimated at two different concentration levels (1 and 5 µg/kg) and ranged from 75% to 101%. The interday and intraday laboratory precisions were lower than 7%. The matrix effect, the recovery of the extraction process, and the overall process efficiency were evaluated. No significant ME was observed in the two matrices considered. This method was applied to the analysis of 75 samples, coming from official controls implemented by the Lazio Region (Central Italy). In one sample of dry-cured ham, the concentration found (69.3 µg/kg) was well above the guidance value recommended by the Italian Ministry of Health (1 µg/kg). These data together with the detection of OTA in three grated cheeses suggest the importance of monitoring these products. Considering the high dietary intake of these matrices, especially among vulnerable populations, further research should be devoted to estimate exposure and risk assessment for OTA.

The Occurrence of Five Unregulated Mycotoxins Most Important for Traditional Dry-Cured Meat Products

This study investigated the occurrence of 5 unregulated mycotoxins in a total of 250 traditional dry-cured meat products sampled in 2020 and 2021 in five Croatian regions (eastern, northern, central, western, and southern). Aflatoxin B₁ (AFB₁), ochratoxin A (OTA), sterigmatocystin (STC), citrinin (CIT), and cyclopiazonic acid (CPA) concentrations were related to the geographical region of the product’s origin and to local weather. The results revealed the contamination of 27% of samples, namely, STC in 4% of samples in concentrations of up to 3.93 µg/kg, OTA in 10% of samples in concentrations of up to 4.81 µg/kg, and CPA in 13% of samples in concentrations of up to 335.5 µg/kg. No AFB₁ or CIT contamination was seen. Although no statistically significant differences in concentrations of individual mycotoxins across the production regions were found, differences in mycotoxin occurrence were revealed. The eastern and western regions, with moderate climate, delivered the largest number of contaminated samples, while the southern region, often compared with subtropics, delivered the smallest, so that the determined mycotoxins were probably mainly produced by the Penicillium rather than the Aspergillus species. Due to the interaction of various factors that may affect mycotoxin biosynthesis during production, the detected concentrations cannot be related solely to the weather.

Investigation of ochratoxin a in blood sausages in the Czech Republic: Comparison with data over Europe

Blood sausages consisting of groats, pork, porcine offal, fat, blood, and spices are very popular in the Czech Republic. All these ingredients are potential sources of dietary exposure to ochratoxin A (OTA). OTA has a strong affinity to serum proteins in porcine blood. Thus, the contamination of blood sausages with OTA can be expected. This study aims to evaluate OTA in 200 samples of porcine blood sausages purchased at the Czech market during 2020-2021. The analytical method high-performance liquid chromatography coupled with fluorescence detection with pre-treatment using immunoaffinity columns was employed to determine OTA. The limit of detection was 0.03 ng/g and the limit of quantification 0.10 ng/g. Recovery was 71.6 %. All samples were positive at contents ranging from 0.15 to 5.68 ng/g with a mean of 1.47 ng/g, and a median of 1.26 ng/g. A total of 66% of these samples contained OTA content exceeding the maximum limit of 1 ng/g set in Italy. This study demonstrates that the Czech population is exposed to OTA from blood sausages. The proposed preliminary action limit for OTA in blood sausages should be set at 1 ng/g. No regulatory limits for OTA in blood sausages have been established yet in the European Union legislation. To protect human health, further monitoring of OTA in these products is necessary.

Ochratoxin A: Occurrence and recent advances in detoxification

Ochratoxin A (OTA), one of the most important mycotoxins, is mainly produced by fungi in the genera Aspergillus and Penicillium, and commonly found in food and agricultural products. In addition to causing significant economic losses, the occurrence of OTA in foods poses a serious threat to human health. Therefore, it is very important to develop approaches to control or detoxify OTA contamination and thus ensure food safety. In this paper, we review the source and occurrence of OTA in food and agricultural products and the latest achievements in the removal and detoxification of OTA using physical, chemical, and biological methods, with specific attention to influencing factors and mechanisms related to the biodetoxification of OTA. Moreover, the advantages and disadvantages of these methods and their potential application prospect were also discussed.

Ochratoxin A in Slaughtered Pigs and Pork Products

Ochratoxin A (OTA) is a mycotoxin that is produced after the growth of several Aspergillus and Penicillium spp. in feeds or foods. OTA has been proved to possess nephrotoxic, hepatotoxic, teratogenic, neurotoxic, genotoxic, carcinogenic and immunotoxic effects in animals and humans. OTA has been classified as possibly carcinogenic to humans (Group 2B) by the IARC in 2016. OTA can be mainly found in animals as a result of indirect transmission from naturally contaminated feed. OTA found in feed can also contaminate pigs and produced pork products. Additionally, the presence of OTA in pork meat products could be derived from the direct growth of OTA-producing fungi or the addition of contaminated materials such as contaminated spices. Studies accomplished in various countries have revealed that pork meat and pork meat products are important sources of chronic dietary exposure to OTA in humans. Various levels of OTA have been found in pork meat from slaughtered pigs in many countries, while OTA levels were particularly high in the blood serum and kidneys of pigs. Pork products made from pig blood or organs such as the kidney or liver have been often found to becontaminated with OTA. The European Union (EU) has established maximum levels (ML) for OTA in a variety of foods since 2006, but not for meat or pork products. However, the establishement of an ML for OTA in pork meat and meat by-products is necessary to protect human health.

Pathways of Mycotoxin Occurrence in Meat Products: A Review

Documented cases of mycotoxin occurrence in meat products call for further research into potential contamination sources, especially given an ever more increasing consumption of these nutritionally rich products. These foodstuffs can be contaminated with mycotoxins through three pathways: contaminated spices and other raw materials, mycotoxin-producing moulds present on the surface of dry-cured meat products, and carry-over effect from farm animals exposed to contaminated feed. In order to establish meat products’ mycotoxin contamination more precisely, the concentrations of all mycotoxins of relevance for these products should be determined. This manuscript reviews data on major mycotoxins present in different types of meat products, and discusses the contamination pathways, contamination levels and control & preventative measures.

Mycobiota and Mycotoxin Contamination of Traditional and Industrial Dry-Fermented Sausage Kulen

The aim of this study was to identify and compare surface mycobiota of traditional and industrial Croatian dry-fermented sausage Kulen, especially toxicogenic species, and to detect contamination with mycotoxins recognized as the most important for meat products. Identification of mould species was performed by sequence analysis of beta- tubulin and calmodulin gene, while the determination of mycotoxins aflatoxin B₁ (AFB₁), ochratoxin A (OTA), and cyclopiazonic acid (CPA) was carried out using the LC-MS/MS (liquid chromatography-tandem mass spectrometry) method. The results showed a significantly higher number of mould isolates and greater species (including of those mycotoxigenic) diversity in traditional Kulen samples in comparison with the industrial ones. P. commune, as a potential CPA-producer, was the most represented in traditional Kulen (19.0%), followed by P. solitum (16.6%), which was the most represented in industrial Kulen samples (23.8%). The results also showed that 69% of the traditional sausage samples were contaminated with either CPA or OTA in concentrations of up to 13.35 µg/kg and 6.95 µg/kg, respectively, while in the industrial samples only OTA was detected (in a single sample in the concentration of 0.42 µg/kg). Mycotoxin AFB₁ and its producers were not detected in any of the analysed samples (<LOD).

Potential of Near Infrared Spectroscopy as a Rapid Method to Discriminate OTA and Non-OTA-Producing Mould Species in a Dry-Cured Ham Model System

The ripening process of dry-cured meat products is characterised by the development of fungi on the product's surface. This population plays a beneficial role, but, uncontrolled moulds represent a health risk, since some of them may produce mycotoxins, such as ochratoxin A (OTA). The aim of the present work is to assess the potential of near-infrared spectroscopy (NIRS) for the detection of OTA-producing mould species on dry-cured ham-based agar. The collected spectra were used to develop Support Vector Machines-Discriminant Analysis (SVM-DA) models by a hierarchical approach. Firstly, an SVM-DA model was tested to discriminate OTA and non-OTA producers; then, two models were tested to discriminate species among the OTA producers and the non-OTA producers. OTA and non-OTA-producing moulds were discriminated with 85% sensitivity and 86% specificity in the prediction. Furthermore, the SVM-DA model could differentiate non-OTA-producing species with a 95% sensitivity and specificity. Promising results were obtained for the prediction of the four OTA-producing species tested, with a 69% and 90% sensitivity and specificity, respectively. The preliminary approach demonstrated the high potential of NIR spectroscopy, coupled with Chemometrics, to be used as a real-time automated routine monitorization of dry-cured ham surfaces.

Antioxidative Effects of Curcumin on the Hepatotoxicity Induced by Ochratoxin A in Rats

Ochratoxin A (OTA) is a powerful mycotoxin found in various foods and feedstuff, responsible for subchronic and chronic toxicity, such as nephrotoxicity, hepatotoxicity, teratogenicity, and immunotoxicity to both humans and several animal species. The severity of the liver damage caused depends on both dose and duration of exposure. Several studies have suggested that oxidative stress might contribute to increasing the hepatotoxicity of OTA, and several antioxidants, including curcumin (CURC), have been tested to counteract the toxic hepatic action of OTA in various classes of animals. Therefore, the present study was designed to evaluate the protective effect of CURC, a bioactive compound with different therapeutic properties on hepatic injuries caused by OTA in rat animal models. CURC effects were examined in Sprague Dawley rats treated with CURC (100 mg/kg), alone or in combination with OTA (0.5 mg/kg), by gavage daily for 14 days. At the end of the experiment, rats treated with OTA showed alterations in biochemical parameters and oxidative stress in the liver. CURC dosing significantly attenuated oxidative stress and lipid peroxidation versus the OTA group. Furthermore, liver histological tests showed that CURC reduced the multifocal lymphoplasmacellular hepatitis, the periportal fibrosis, and the necrosis observed in the OTA group. This study provides evidence that CURC can preserve OTA-induced oxidative damage in the liver of rats.

Ochratoxin A contamination of the casing and the edible portion of artisan salamis produced in two Italian regions

The purpose of this study was to provide data on the presence of ochratoxin A (OTA) in artisan salamis produced in the Campania and Marche regions (Italy). For this aim, 96 different salamis were purchased from farms and small salami factories. Analysis were carried out firstly on the casings of all samples, and in a second step, in the outer and inner edible parts of those samples whose casings were found positive for OTA at concentration levels above the Italian guideline value established for OTA in pork meat (1 μg/kg). The analytical method, based on a sample preparation procedure with immunoaffinity columns, together with analysis by LC-MS/MS, has guaranteed average recoveries between 79.4 and 89.0%, limits of detection (LOD) and quantification (LOQ) of 0.10 and 0.25 μg/kg, respectively. OTA was detected in 25.0% of the analysed casings (24 samples) at concentration ranging from 0.25 to 98.52 μg/kg. Ten of these samples were from the same production plant in which an additional sampling was carried out, and where a problem of environmental contamination by ochratoxigenic moulds probably exists. The edible parts were mostly uncontaminated, except in 3 samples, 2 of which showed OTA contamination levels above 1 μg/kg. The presence of OTA on the casing does not seem to be cause for alarm about the safety of this type of product but it should in any case be monitored. Before slicing the meat for consumption, it is always good practice to peel the casing even if reported as edible on salami label.

Selection and Evaluation of Staphylococcus xylosus as a Biocontrol Agent against Toxigenic Moulds in a Dry-Cured Ham Model System

Toxigenic moulds can develop on the surface of dry-cured meat products during ripening due to their ecological conditions, which constitutes a risk for consumers. A promising strategy to control this hazard is the use of antifungal microorganisms usually found in these foods. However, to date, the effectiveness of gram-positive catalase-positive cocci (GCC+) has not been explored. The aim of this work was to select GCC+ isolates with antifungal activity to study its effectiveness in a dry-cured ham model system at the environmental conditions reached during the ripening. Forty-five strains of GCC+ were evaluated and the isolate Staphylococcus xylosus Sx8 was selected to assess its efficacy at two different concentrations (106 and 104 cfu/mL) against Penicillium nordicum, Aspergillus flavus, Aspergillus parasiticus, and Penicillium griseofulvum at 15, 20, and 25 °C. The results showed that the inoculation of 106 cfu/mL of S. xylosus completely inhibited the growth of most fungi. In addition, in the presence of this strain at 104 cfu/mL, a significant reduction in fungal growth and mycotoxins production was observed at the three temperatures studied. In conclusion, S. xylosus Sx8 possesses great potential as a biological agent to control toxigenic moulds in dry-cured meat products.

Risk assessment of ochratoxin A in food

The European Commission asked EFSA to update their 2006 opinion on ochratoxin A (OTA) in food. OTA is produced by fungi of the genus Aspergillus and Penicillium and found as a contaminant in various foods. OTA causes kidney toxicity in different animal species and kidney tumours in rodents. OTA is genotoxic both in vitro and in vivo; however, the mechanisms of genotoxicity are unclear. Direct and indirect genotoxic and non-genotoxic modes of action might each contribute to tumour formation. Since recent studies have raised uncertainty regarding the mode of action for kidney carcinogenicity, it is inappropriate to establish a health-based guidance value (HBGV) and a margin of exposure (MOE) approach was applied. For the characterisation of non-neoplastic effects, a BMDL 10 of 4.73 μg/kg body weight (bw) per day was calculated from kidney lesions observed in pigs. For characterisation of neoplastic effects, a BMDL 10 of 14.5 μg/kg bw per day was calculated from kidney tumours seen in rats. The estimation of chronic dietary exposure resulted in mean and 95th percentile levels ranging from 0.6 to 17.8 and from 2.4 to 51.7 ng/kg bw per day, respectively. Median OTA exposures in breastfed infants ranged from 1.7 to 2.6 ng/kg bw per day, 95th percentile exposures from 5.6 to 8.5 ng/kg bw per day in average/high breast milk consuming infants, respectively. Comparison of exposures with the BMDL 10 based on the non-neoplastic endpoint resulted in MOEs of more than 200 in most consumer groups, indicating a low health concern with the exception of MOEs for high consumers in the younger age groups, indicating a possible health concern. When compared with the BMDL 10 based on the neoplastic endpoint, MOEs were lower than 10,000 for almost all exposure scenarios, including breastfed infants. This would indicate a possible health concern if genotoxicity is direct. Uncertainty in this assessment is high and risk may be overestimated.

Effects of Curcumin on the Renal Toxicity Induced by Ochratoxin A in Rats

Ochratoxin A (OTA) is a powerful nephrotoxin and the severity of its damage to kidneys depends on both the dose and duration of exposure. According to the scientific data currently available, the mechanism of action still is not completely clarified, but it is supposed that oxidative stress is responsible for OTA-induced nephrotoxicity. Bioactive compound use has emerged as a potential approach to reduce chronic renal failure. Therefore, curcumin (CURC), due to its therapeutic effects, has been chosen for our study to reduce the toxic renal effects induced by OTA. CURC effects are examined in Sprague Dawley rats treated with CURC (100 mg/kg), alone or in combination with OTA (0.5 mg/kg), by gavage daily for 14 days. The end result of the experiment finds rats treated with OTA show alterations in biochemical and oxidative stress parameters in the kidney, related to a decrease in the Glomerular Filtration Rate (GFR). Conversely, the administration of CURC attenuates oxidative stress and prevents glomerular hyperfiltration versus the OTA group. Furthermore, kidney histological tests show a reduction in glomerular and tubular damage, inflammation and tubulointerstitial fibrosis. This study shows that CURC can mitigate OTA-induced oxidative damage in the kidneys of rats.

Effects of environmental conditions and substrate on growth and ochratoxin A production by Penicillium verrucosum and Penicillium nordicum: Relative risk assessment of OTA in dry-cured meat products

Ecological conditions during ripening of dry-cured meat products favour the growth of an uncontrolled mould population that could suppose a risk of ochratoxin A (OTA) production. In this work the influence of water activity (a_w), temperature and substrate composition on fungal growth and OTA production by Penicillium nordicum and Penicillium verrucosum isolated from dry-cured meat products have been studied. In addition, the relative risk of OTA presence on dry-cured meat products has been evaluated using the Risk Ranger software. Fungal growth was observed in the range of 0.99-0.90 a_w and 15-25 °C being mainly temperature-dependent. P. nordicum and P. verrucosum were able to produce OTA in every substrate in these ranges of a_w and temperature. The production of OTA by P. verrucosum was mainly influenced by temperature and media composition. However, P. nordicum it is affected mainly by substrate or temperature depending on the strain studied. Both species produce a large amount of OTA on dry-cured ham and on dry-cured fermented sausage "salchichón" in environmental conditions usually found throughout the ripening of these products. The Risk Ranger software reveals that the relative risk of OTA on dry-cured meat products is 75%. Thus, control measures during dry-cured meat products processing to prevent OTA risk should be established.

Occurrence of ochratoxin A in typical salami produced in different regions of Italy

A total of 172 different salamis were purchased from farms and small salami factories located in four Italian regions (Piedmont, Veneto, Calabria, and Sicily) and analyzed for the presence of ochratoxin A (OTA). Analysis was performed by high-performance liquid chromatography coupled to a fluorimetric detector (HPLC-FLD). The detection limit (LOD) for the method used was 0.05 μg/kg, while the quantitation limit (LOQ) was 0.20 μg/kg; the average recovery rate was 89.1%. OTA was detected in 22 salamis, and 3 samples exceeded the Italian guidance value for OTA in pork meat (1 μg/kg). In particular, what emerges from this research is the high percentage of spicy salamis among positive samples (68.2%, 15 out of 22), although spicy salamis are only 27.3% of the total number of samples collected and analyzed. Red chili pepper contaminated by OTA could be responsible for the presence of the mycotoxin in these spicy salamis. It follow that, also the control of some ingredients used in the manufacture of these meat products, like spices, should not be neglected.

Ochratoxin A Control in Meat Derivatives: Intraspecific Biocompetition betweenPenicillium nordicumStrains

APenicillium nordicumstrain previously assessed for its atoxigenicity was tested against a toxigenic strain of the same species on salami, in order to assess its effectiveness as a biocontrol agent for OTA containment. Sixtysalamiwere inoculated with different combinations ofP. nordicumOTA−/OTA+ suspensions and ripened under controlled thermohygrometric conditions. After 7, 18, 29, and 40 days, both fungal counts and chemical analyses were carried out on casings. OTA was never found insalamiused as a control, while it was occasionally detected in traces (0.08–0.76 μg/kg) insalamiinoculated with the atoxigenicP. nordicumstrain. It was otherwise detected at levels varying from 2.84 to 15.85 μg/kg in coinoculated salami and from 48.66 to 177.79 μg/kg insalamiinoculated with the toxigenicP. nordicumstrain. OTA levels detected when coinoculation occurred were 91.1%, 85.8%, and 94.2% lower than those found in samples inoculated with the toxigenic strain, respectively, after 18, 29, and 40 ripening days. Biocontrol approach using intraspecific competition proved very effective in reducing both settlement of toxigenic strains and OTA contamination and could be therefore considered an interesting strategy to avoid OTA contamination in moulded meats, if used in association with fungal commercial starters.

Effect of temperature and water activity on growth and aflatoxin production by Aspergillus flavus and Aspergillus parasiticus on cured meat model systems

Dry-cured hams may be colonised by aflatoxin-producing Aspergillus flavus and Aspergillus parasiticus during the ripening process. The objective of this study was to evaluate the interaction between non-ionic water stress and temperatures may have on lag phases prior to growth, growth rates and aflatoxin production by two strains of each A. parasiticus and A. flavus on meat matrices over a period of 12days. Results showed that A. flavus CBS 573.65 had shorter lag phases than A. parasiticus CECT 2688, however the growth rates were quite similar. For both species, no growth occurred at 10°C and all aw tested and optimum growth happened at 25°C and 0.95 aw. Similar aflatoxin B1 production profiles between both species were found, however A. flavus produced much higher concentration of such toxin than A. parasiticus. Both species produced aflatoxins when the temperature and the aw were ≥15°C and ≥0.90.

Rapid prediction of ochratoxin A-producing strains of Penicillium on dry-cured meat by MOS-based electronic nose

The availability of rapid diagnostic methods for monitoring ochratoxigenic species during the seasoning processes for dry-cured meats is crucial and constitutes a key stage in order to prevent the risk of ochratoxin A (OTA) contamination. A rapid, easy-to-perform and non-invasive method using an electronic nose (e-nose) based on metal oxide semiconductors (MOS) was developed to discriminate dry-cured meat samples in two classes based on the fungal contamination: class P (samples contaminated by OTA-producing Penicillium strains) and class NP (samples contaminated by OTA non-producing Penicillium strains). Two OTA-producing strains of Penicillium nordicum and two OTA non-producing strains of Penicillium nalgiovense and Penicillium salamii, were tested. The feasibility of this approach was initially evaluated by e-nose analysis of 480 samples of both Yeast extract sucrose (YES) and meat-based agar media inoculated with the tested Penicillium strains and incubated up to 14 days. The high recognition percentages (higher than 82%) obtained by Discriminant Function Analysis (DFA), either in calibration and cross-validation (leave-more-out approach), for both YES and meat-based samples demonstrated the validity of the used approach. The e-nose method was subsequently developed and validated for the analysis of dry-cured meat samples. A total of 240 e-nose analyses were carried out using inoculated sausages, seasoned by a laboratory-scale process and sampled at 5, 7, 10 and 14 days. DFA provided calibration models that permitted discrimination of dry-cured meat samples after only 5 days of seasoning with mean recognition percentages in calibration and cross-validation of 98 and 88%, respectively. A further validation of the developed e-nose method was performed using 60 dry-cured meat samples produced by an industrial-scale seasoning process showing a total recognition percentage of 73%. The pattern of volatile compounds of dry-cured meat samples was identified and characterized by a developed HS-SPME/GC-MS method. Seven volatile compounds (2-methyl-1-butanol, octane, 1R-α-pinene, d-limonene, undecane, tetradecanal, 9-(Z)-octadecenoic acid methyl ester) allowed discrimination between dry-cured meat samples of classes P and NP. These results demonstrate that MOS-based electronic nose can be a useful tool for a rapid screening in preventing OTA contamination in the cured meat supply chain.

Occurrence and potential transfer of mycotoxins in gilthead sea bream and Atlantic salmon by use of novel alternative feed ingredients

Plant ingredients and processed animal proteins (PAP) are suitable alternative feedstuffs for fish feeds in aquaculture practice, although their use can introduce contaminants that are not previously associated with marine salmon and gilthead sea bream farming. Mycotoxins are well known natural contaminants in plant feed material, although they also could be present on PAPs after fungi growth during storage. The present study surveyed commercially available plant ingredients (19) and PAP (19) for a wide range of mycotoxins (18) according to the EU regulations. PAP showed only minor levels of ochratoxin A and fumonisin B1 and the mycotoxin carry-over from feeds to fillets of farmed Atlantic salmon and gilthead sea bream (two main species of European aquaculture) was performed with plant ingredient based diets. Deoxynivalenol was the most prevalent mycotoxin in wheat, wheat gluten and corn gluten cereals with levels ranging from 17 to 814 and μg kg(-1), followed by fumonisins in corn products (range 11.1-4901 μg kg(-1) for fumonisin B1+B2+B3). Overall mycotoxin levels in fish feeds reflected the feed ingredient composition and the level of contaminant in each feed ingredient. In all cases the studied ingredients and feeds showed levels of mycotoxins below maximum residue limits established by the Commission Recommendation 2006/576/EC. Following these guidelines no mycotoxin carry-over was found from feeds to edible fillets of salmonids and a typically marine fish, such as gilthead sea bream. As far we know, this is the first report of mycotoxin surveillance in farmed fish species.

Producers and important dietary sources of ochratoxin A and citrinin

Ochratoxin A (OTA) is a very important mycotoxin, and its research is focused right now on the new findings of OTA, like being a complete carcinogen, information about OTA producers and new exposure sources of OTA. Citrinin (CIT) is another important mycotoxin, too, and its research turns towards nephrotoxicity. Both additive and synergistic effects have been described in combination with OTA. OTA is produced in foodstuffs by Aspergillus Section Circumdati (Aspergillus ochraceus, A. westerdijkiae, A. steynii) and Aspergillus Section Nigri (Aspergillus carbonarius, A. foetidus, A. lacticoffeatus, A. niger, A. sclerotioniger, A. tubingensis), mostly in subtropical and tropical areas. OTA is produced in foodstuffs by Penicillium verrucosum and P. nordicum, notably in temperate and colder zones. CIT is produced in foodstuffs by Monascus species (Monascus purpureus, M. ruber) and Penicillium species (Penicillium citrinum, P. expansum, P. radicicola, P. verrucosum). OTA was frequently found in foodstuffs of both plant origin (e.g., cereal products, coffee, vegetable, liquorice, raisins, wine) and animal origin (e.g., pork/poultry). CIT was also found in foodstuffs of vegetable origin (e.g., cereals, pomaceous fruits, black olive, roasted nuts, spices), food supplements based on rice fermented with red microfungi Monascus purpureus and in foodstuffs of animal origin (e.g., cheese).