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Farmers, cereal suppliers and processors demand rapid techniques for the assessment of mould-associated contamination. Deoxynivalenol (DON) is among the most important Fusariumtoxins and related to human and animal diseases besides causing significant economic losses. Routine analytical techniques for the analysis of DON are either based on chromatographic or immunoanalytical techniques, which are time-consuming and frequently rely on hazardous consumables. The present study evaluates the feasibility of infrared attenuated total reflection spectroscopy (IR-ATR) for the analysis of maize extracts viadifferent solvents optimized for the determination of DON contamination along the regulatory requirements by the European Union (EU) for unprocessed maize (1750 μg kg−1). Reference analysis was done by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). The studied maize samples were either naturally infected or had been artificially inoculated in the field with Fusarium graminearum, Fusarium culmorumor Fusarium verticillioides. Principal component analysis demonstrated that water and methanol–water (70 : 30% v) were optimum solvents for differentiating DON contamination levels. Supervised partial least squares discriminant analysis resulted in excellent classification accuracies of 86.7% and 90.8% for water and methanol–water extracts, respectively. The IR spectra of samples with fungal infection and high DON contamination had distinct spectral features, which could be related to carbohydrates, proteins and lipid content within the investigated extracts.

•Monitoring of biomarkers reveal the exposure to AF, OTA and DON, mainly.•Biomarkers results in blood and urine give complementary exposure information.•Improved instrumental techniques enable multimycotoxin detection.•Few studies deal with simultaneous exposure to mycotoxins and other chemical hazards.•There is a need to include the mycotoxins in exposome approaches.

Fungal pathogens cause surface contamination and potential premature fruit spoilage of bambinella, a fruit endemic to the Maltese islands, leading to the loss of fruit during the postharvest phase. The objective of this study was to isolate, quantify, and characterize fungal contaminants of the small Maltese June Pear and describe their growth kinetics. In total, 284 fungicide-free fruits were collected over three consecutive summers (2014, 2015, 2016). The isolated fungi were identified by using forward and reverse colonial morphology. Species identification was determined using PCR-based methods. The number of CFU per square centimeter of bambinella outer skin was calculated. Mycelium diameter growth rate studies of the isolates were also carried out at seven different temperatures, ranging from 5 to 35°C. Fungi isolated from bambinella included Cladosporium ramotenellum, Alternaria arborescens, Penicillium lanosum, Penicillium expansum,and Aspergillus sydowii,listed from the most abundant to the least abundant. The Rosso model was fitted to the growth kinetic data and showed that the optimal temperatures for growth of all five fungi were in the range of 20 to 22°C, whereas growth was slower at temperatures below 10°C and above 30°C. As observed in the diameter studies, the order of highest to lowest germination rate was found to be P. expansum, A. sydowii, P. lanosum, C. ramotenellum,and A. arborescens. Germination studies showed that the highest germination rate was observed for P. lanosum,followed by A. arborescens, C. ramotenellum, P. expansum,and A. sydowii,in descending order. The highest germination lag time was observed for A. arborescens,followed by C. ramotenellum, P. expansum, P. lanosum,and A. sydowii,in ascending order.

•Postharvest mycotoxins contamination represents a worldwide problem.•Predictive models on mycotoxin production in foods are scarce.•Luedeking-Piret, Baranyi, polynomial and logistic models are the main mathematical approaches.•A number of challenges need to be solved before they are applied in food safety management.

•Deoxynivalenol is not completely removed through wheat processing.•Milling and ozonation are the food processes with the highest deoxynivalenol reduction.•Deoxynivalenol can increase during breadmaking process, due to release from flour.•There is a high increase of deoxynivalenol-3-glucoside during breadmaking process.•More information about deoxynivalenol degradation products is necessary.

The aim of this work was to use probability models for the prediction of growth and aflatoxin production by Aspergillus flavusas a strategy to mitigate the aflatoxin presence in pistachio nuts during postharvest. Logistic models, with temperature and time as explanatory variables, were fitted to the probability of growth and aflatoxin B1(AFB1) production under constant temperature levels, afterwards they were used to predict probabilities under non-isothermal scenarios. The models obtained showed levels of concordance from 80 to 100% in most of the cases. Moreover, the presence of AFB1 in pistachio nuts could be correctly predicted through AFB1 models developed in agar medium or through growth models in pistachio nuts. These findings can support decision making, at transport and storage level, and could be used by producers and processors to predict the time for AFB1 production by A. flavusin pistachio nuts in postharvest.

The effect of the application of two fungicides (cyprodinil alone and a mixture of cyprodinil and fludioxonil) on the mycoflora of grapes, especially ochratoxigenic fungi, was studied. Different doses and application times were analyzed. Grape mycobiota was isolated and identified, and the classification of black aspergilli was carried out. We found that 81.7% of the isolates belonged to Aspergillus nigeraggregate and 18.3% to Aspergillus carbonarius. The ability to produce ochratoxin A (OTA) was studied on Czapek yeast extract agar (CYA) medium in 238 isolates. Most A. carbonarius(97.2%) produced detectable amounts of OTA, while only 2.9% of the A. nigeraggregate were OTA producers. Most of the isolates (58%) produced less than 2.5 μg OTA per g of CYA. That, together with the highest levels of black aspergilli detected near harvest, proved the reported theory that they are primarily responsible for OTA in grapes. The fungicides studied had a significant effect on black aspergilli in three of the four vineyards sampled, as the natural increase of black aspergilli when approaching harvest was in general lower in all the fields treated with fungicides as compared to the control treatment. A mixture of cyprodinil (37.5%) and fludioxonil (25%) applied at veraison and 21 days before harvest was the most effective treatment to prevent black aspergilli in grapes, together with a single application of this mixture at veraison followed by an application of cyprodinil (50%) 21 days before harvest. No OTA was detected in musts (n= 112) produced from either the control treatment or the treated grapes.

The objective of this work was to determine the effects of extrusion cooking on the stability of ochratoxin A (OTA) in an artificially contaminated hulled barley meal (0.73-mm grain diameter) using a single screw extruder. The extrusion cooking parameters were temperature (140, 160, and 180°C), initial moisture content of barley meal (24, 27 and 30%), and residence time (30, 40, 50, 60, and 70 s). Both unextruded and extruded samples were analyzed for OTA by high-performance liquid chromatography. Extrusion cooking variables significantly affected the stability of OTA (P< 0.05). Greater OTA reductions were achieved at higher residence time (70 s), medium temperature level (160°C), and either high (30%) or low moisture (24%) content of samples. The amount of OTA destroyed during the extrusion process ranged from 17 to 86% depending on the studied parameters. The decrease in the amount of OTA after extrusion cooking followed first-order kinetics, showing that the fastest treatment in OTA reduction was that at 140°C and 24% of moisture content.

Forty vineyards from four wine making regions of Spain were sampled at three different growth stages in 2002 and 2003. The aim was to study the fungi associated with grapes and their ability to produce ochratoxin A (OTA) on synthetic media. Among the total mycoflora, 464 (7.7%) and 648 (10.8%) Aspergillussection Nigri(black aspergilli) strains were isolated in 2002 and 2003, respectively, and were classified into three groups: isolates with uniseriate heads, A. nigeraggregate and A. carbonarius. The latter presented the highest percentage of OTA-positive strains (82% in 2002 and 76% in 2003) and produced the highest levels of toxin (2.5–25 μg g−1). The sampling year, sampling date, the region and their interactions presented significant differences in the number of black aspergilli isolated. Most black aspergilli were found in 2003 and at harvest. A positive correlation between the number of black aspergilli found in grapes and the temperature in the field was found. Grapes from 2003, the warmest year, and from Costers del Segre, the warmest region, were significantly the most contaminated. No significant correlation between black aspergilli presence and other meteorological factors such as relative humidity or rainfall could be established. Musts from all the vineyards were also analysed in both years, although no OTA was found in either year.

This review focuses on the fumonisin-producing Fusariumspecies and the ecophysiology of these species. The effects of environmental biotic and abiotic factors on germination, growth, and fumonisin B1production by Fusarium verticillioidesand Fusarium proliferatumhave been investigated under laboratory, field, and storage conditions. An understanding of the factors involved in production of fumonisins is the first step in preventing accumulation of these toxins.

The effect of cinnamon, clove, oregano, palmarosa and lemongrass oils on fumonisin B1 (FB1) accumulation by one isolate each ofFusarium verticillioidesandFusarium proliferatumin non-sterilised naturally contaminated maize grain at 0.995 and 0.950awand at 20 and 30 °C was evaluated. The concentration used was 500 mg kg-1maize. Under these conditions it was shown that antimycotoxigenic ability only took place at the higher water availabilities, and mostly at 20 °C. Only cinnamon, lemongrass and palmarosa oils were somewhat effective. Moreover, it was suggested that competing mycoflora plays an important role in FB1accumulation. It was concluded that the efficacy of essential oils in real substrates, such as cereals, may be much lower than in synthetic media; different essential oils may be found to be useful and at different concentrations. Their effectiveness is highly dependent on both abiotic and biotic factors involved.The effect of cinnamon, clove, oregano, palmarosa and lemongrass oils on fumonisin B1 (FB1) accumulation by one isolate each ofFusarium verticillioidesandFusarium proliferatumin non-sterilised naturally contaminated maize grain at 0.995 and 0.950awand at 20 and 30 °C was evaluated. The concentration used was 500 mg kg-1maize. Under these conditions it was shown that antimycotoxigenic ability only took place at the higher water availabilities, and mostly at 20 °C. Only cinnamon, lemongrass and palmarosa oils were somewhat effective. Moreover, it was suggested that competing mycoflora plays an important role in FB1accumulation. It was concluded that the efficacy of essential oils in real substrates, such as cereals, may be much lower than in synthetic media; different essential oils may be found to be useful and at different concentrations. Their effectiveness is highly dependent on both abiotic and biotic factors involved.

The effects of temperature and water availability on growth and interactions between fumonisin-producing isolates of Fusarium moniliforme and F. proliferatum and seven other fungi from maize grain were determined in vitro. The type of interaction and index of dominance (ID) between species were markedly influenced by temperature and aw. Generally, F. moniliforme and F. proliferatum were very competitive and dominant against the Penicillium spp. and A. flavus. They were in turn dominated by A. niger, but mutually antagonistic when paired with F. graminearum and A. ochraceus. Under slightly drier conditions (&lt;0·98 aw) A. ochraceus became more competitive and dominant over the fumonisin-producing species. A. flavus was dominant only at 30°C and &lt;0·96 aw. F. moniliforme and F. proliferatum demonstrated dominance against all species over a range of temperatures and 0·994 to 0·96 aw. At lower aw levels they were less competitive. The growth rate of the two fumonisin-producing species was significantly reduced by F. graminearum, regardless of aw. F. moniliforme and F. proliferatum reduced growth of Penicillium and Aspergillus spp., especially at >0·96 aw. At &lt;0·96 aw, growth of these species was unaffected. Using Biolog plates the effect of aw and temperature on utilization patterns of carbon sources in maize were evaluated for the first time. The niche overlap indices relative to F. moniliforme and F. proliferatum were determined and compared with that of each interacting species. NOIs for F. moniliforme and F. proliferatum were >0·90 at >0·96 aw and 25 and 30°, indicative of co-existence with other species. Most of species had NOIs >0·90, except in some cases when paired with F. moniliforme, where NOIs &lt;0·80 suggested the occupation of different niches. Although there was no significant correlation between the ID and NOI methods both suggested that the niche overlap between species was in a state of flux and significantly influenced by both temperature and water availability. This suggests that interpretation of ID, or NOIs carried out under one set of environmental conditions may be misleading when considering interactions between species and also where screening for biocontrol potential is being considered.

The effect of water activity (aw, 0·995–0·85) and temperature (15, 25°C) on the in vitro inter- and intra-specific interactions between thirteen fungi commonly isolated from maize grain were investigated. The fungi were paired and their interactions given a numerical score to obtain an Index of Dominance (ID) for each species. Aspergillus niger had the highest overall ID in most of the conditions tested, while the Aspergillus species tested were also quite dominant. Fusarium species appeared to be dominant only at high water availability (0·995 aw), while Eurotium species dominated at the lower aws (0·85–0·90). The relative growth rates of each fungus were also calculated under the same range of environmental conditions. In general, Aspergillus, Fusarium and Trichoderma species grew most rapidly under the combination of aw and temperature conditions in which they were able to grow, while Penicillium species had the slowest growth rates. There was a positive correlation between growth rate and ID for Trichoderma viride and three Fusarium spp. but not for Aspergillus and Penicillium and Eurotium spp. The different possible strategies in fungal competition for grain are discussed in relation to these in vitro findings.

•Predictive mycology is increasingly used for shelf life estimations in foodstuffs.•Mycotoxin risks have been calculated using probability models.•Predictive modelling is useful to evaluate the impact of climate change in mycotoxins.•Modelling of spectroscopic responses of samples is used to predict mycotoxin presence.