Amedeo Reyneri

Nutritional and technological quality of bread enriched with an intermediated pearled wheat fraction

A strategy to maximise the health benefits of wheat-based products enriched with refined flour and selected fractions of kernel, obtained by sequential pearling, has been tested. Five mixtures of refined commercial flour with an increasing replacement of a pearled wheat fraction were used to prepare bread and were compared with a control for the dough rheological properties (Mixolab® parameters), the bioactive compound content, deoxynivalenol (DON) contamination and the physical properties (volume, crust colour, instrumental crunchiness and crumb texture profile analysis parameters). The antioxidant and dietary fibre contents increased linearly as the flour was enriched with the pearled fraction. The dietary fibre, β-glucan, total phenolic, alkylresorcinol content and the antioxidant activity increased significantly at a replacement level of 10%, while the technological properties were not significantly different from those of the control. It has been shown that refined flour could be enriched through the addition of a selected wheat pearled fraction and the bioactive compound content of composite bread could be improved, while few rheological and technological differences could be obtained and the risk for DON contamination could be limited.

Relationships between Ostrinia nubilalis (Lepidoptera: Crambidae) feeding activity, crop technique and mycotoxin contamination of corn kernel in northwestern Italy

Abstract The relationships between the feeding activity of Ostrinia nubilalis (Hübner), crop technique (i.e., planting date, nitrogen fertilization, irrigation, and use of deltamethrin), and mycotoxin contamination of kernels were studied in Italian corn crop systems. Field sampling was conducted to determine the incidence of first- and second-generation larvae for each crop technique. At harvest, kernel contamination by fumonisins and zearalenon was measured and related to the number and position of tunnels on corn ears. The number of corn plants injured from second-generation larvae was partially reduced by using deltamethrin (−35%) and by bringing forward planting (−12%), whereas differences in nitrogen and water supply had little effect. The abundance of the first generation was, on average, low. The amount of fumonisin was generally one scale point higher in injured ears, and was positively related to ear tunnelling: tunnels in the apex seem to increase the amount of contamination. No links were detected between O. nubilalis presence and zearalenon contamination.

Influence of agricultural practices on Fusarium infection, fumonisin and deoxynivalenol contamination of maize kernels

Mycotoxins in cereals are an economic and health problem. They are mainly produced in the field and are influenced by environmental conditions during ripening and by agricultural practices. The aim of this research was to evaluate the effect of combined agronomic techniques on fumonisins and deoxynivalenol contamination in maize kernels. Six experimental fields were prepared in North Italy from 2005 to 2007. Two hybrids with different maturity times and 6 different combinations of agricultural practices (sowing time, plant density, N fertilisation and European corn borer (ECB) control with insecticide) were compared for ECB incidence and severity, Fusarium ear rot incidence and severity, F. verticillioides and F. graminearum kernel infection and fumonisin and deoxynivalenol contamination. In temperate climates, where ECB attack is consistent, the production of maize kernels with a low fumonisin content can be enhanced by a correct insecticide application against second-generation ECB larvae and by an earl...

Impact of insecticide treatments on Ostrinia nubilalis (Hübner) (Lepidoptera: Crambidae) and their influence on the mycotoxin contamination of maize kernels.

BACKGROUND European corn borer (ECB), Ostrinia nubilalis (Hübner), is the main maize pest in Central and Southern Europe and promotes the infection of maize with Fusarium spp., which produce mycotoxins. The objective of this study was to determine the effect of insecticide treatments on ECB damage, Fusarium infection and mycotoxin contamination. The field experiments were performed from 2000 to 2006 in three locations in north-western Italy. At harvest, ears were rated for the incidence and severity of ECB damage and Fusarium ear rot symptoms, and the harvested kernels were analysed for fumonisins and zearalenone. RESULTS In all the years except 2003, the chemical treatment had a significant effect on ECB incidence and severity. The ear damage was reduced, on average, by 44.1%. Fusarium ear rot and fumonisin contamination were affected by ECB control. The occurrence of the mycotoxin was significantly reduced, on average by 68%. The differences between the treatments were less clear in the year with highest ECB pressure. No significant difference was observed between the different insecticide classes. No relations were detected between the ECB activity and the occurrence of zearalenone. CONCLUSION This research indicates that the production of kernels with low fumonisin content may be enhanced by an insecticide treatment against the second ECB generation.

Determination of maize kernel hardness: comparison of different laboratory tests to predict dry-milling performance

BACKGROUND Numerous foods are produced from maize, and grain hardness has been described to have an impact on grain end-use value, and in particular for dry-milling performance. RESULTS Thirty-three samples of commercial hybrids have been analysed for test weight (TW), thousand-kernel weight (TKW), hard:soft endosperm ratio (H/S), milling time (MT) and total milling energy (TME) through the Stenvert hardness test, coarse:fine material ratio (C/F), break force (HF) and break energy (HWF) through the puncture test, floating test (FLT), kernel dimensions and sphericity (S), protein (PC), starch (SC), lipid (LC), ash (AC) content and amylose:amylopectin ratio (AS/AP).Total grit yield (TGY) has been obtained through a micromilling procedure and used to compare the efficiency of the tests to predict the dry-milling performance. TW, H/S, MT, TME, C/F, FLT, S, PC, SC and AS/AP were significantly correlated with each other. TW has been confirmed to be a simple estimator of grain hardness. Among the hardness tests, C/F was shown to be the best descriptor of maize milling ability, followed by FLT. A good correlation with TGY has also been observed with H/S, MT, TME and PC, while SC, S and AS/AP seem to play a minor role. The puncture test (HF and HWF) did not offer good indications on the impact of hardness on kernel grinding properties. CONCLUSION This study can be considered as a contribution towards determining kernel properties which influence maize hardness measurement in relation to the end-use processing performance.

Effect of maize crop residue density on Fusarium head blight and on deoxynivalenol contamination of common wheat grains

Fusarium head blight (FHB) of small grain cereals is a worldwide disease that reduces yield and causes deoxynivalenol (DON) contamination in grains. Non-decomposed residues from the previous crop present on the soil surface are considered the principal inoculum sources for Fusarium graminearum and F. culmorum, the most important Fusarium species that cause FHB in Europe. The objective of this study was to investigate the effect of the amount of previous residues on the FHB disease under natural conditions and on DON contamination in soft wheat following grain maize. Field experiments were conducted in two cropping seasons and two sites to compare four maize residue densities on the soil surface and in the first 10 cm of soil in tilled and non-tilled fields. Ploughing to a 30 cmdepth significantly reduced FHB severity (by 63%) and DON occurrence (by 80%) in each year and site. FHB severity and DON contamination significantly increased with the density of the residues left by the preceding crop. This study confirms that conservation tillage may increase DON concentration in wheat grain compared to ploughing which buries residues. This increase varies to a great extent not only because of the annual weather conditions and the nature of the preceding crop, but also because of the amount of infected crop residues remaining on the soil surface, which depends on the soil tillage methods and the preceding crop.

Progressive Pearling of Barley Kernel: Chemical Characterization of Pearling Fractions and Effect of Their Inclusion on the Nutritional and Technological Properties of Wheat Bread

Two hulled barley varieties have been sequentially pearled for one to eight cycles, each with 5% removal. The derived fractions were analyzed for their bioactive compound content. The dietary fiber (DF) decreased from the external to the internal layers, whereas β-glucans showed an inverse trend. Deoxynivalenol contamination was concentrated in the outer layers. The total antioxidant activity (TAA) was higher in the 15-25% fractions, which were used to prepare bread. Five mixtures of refined wheat flour, with an increasing replacement of this pearled barley fraction, were compared with a control for the bioactive compound content, as well as for the rheological and physical bread properties. The inclusion of pearled fractions with up to a 10% substitution leads to a clear enhancement of the DF and TAA, with only minor detrimental effects on the physical parameters. Selected byproducts of barley pearling could be proposed as functional ingredients for bakery products rich in DF and TAA.

Moniliformin analysis in maize samples from North-West Italy using multifunctional clean-up columns and the LC-MS/MS detection method.

A fast clean-up method has been developed to purify maize extracts and to detect moniliformin (MON) in maize samples from North-West Italy over a four-year period (2008–2011). The method is based on the use of MycoSep® 240 Mon clean-up columns (Romer Labs®). Samples were extracted using acetonitrile/water (84:16, v/v), and the extracts were purified with previously described clean-up columns. The liquid chromatography–tandem mass spectrography (LC-MS/MS) analysis has been carried out by means of hydrophilic interaction chromatography (HILIC), combined with negative electrospray mass spectrometry. The method has a recovery of 76–91% (relative standard deviation, RSD%: 6–14%), a limit of detection (LOD) of 1 µg kg–1 and a limit of quantification (LOQ) of 4 µg kg−1. Naturally contaminated maize (108 samples) was analysed for MON content. The average percentages of positive samples was 93% with the following ranges (µg kg−1): 33–2606 (2008);

Effect of fungicide application to control Fusarium head blight and 20 Fusarium and Alternaria mycotoxins in winter wheat (Triticum aestivum L.)

Azole fungicides have been reported to be the most effective active substances in the control of Fusarium Head Blight (FHB) and in the reduction of the main mycotoxins that occur in cereal grain, such as deoxynivalenol (DON). Four field experiments have been conducted in North West Italy, over a period of 2 growing seasons, in order to evaluate the effect of azole fungicide (prothioconazole) applications on the prevalence of emerging mycotoxins in common winter wheat under naturally-infected field conditions. Wheat samples have been analysed by means of a dilute-and-shoot multi-mycotoxin LC-MS/MS method. Twenty fungal metabolites were detected: enniatins, aurofusarin, moniliformin, equisetin, DON, deoxynivalenol-3-glucoside, culmorin, bikaverin, beauvericin, fumonisins, fusaric acid, 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol, nivalenol, zearalenone, decalonectrin, butenolide, tentoxin, alternariol and alternariol methyl ether. The most abundant fungal metabolites were DON and culmorin, with an avera...

Management of fumonisin contamination in maize kernels through the timing of insecticide application against the European corn borer Ostrinia nubilalis Hübner

The European corn borer (ECB), Ostrinia nubilalis, is the principal pest of maize in Central and South Europe. It is known to promote Fusarium verticillioides infection in maize grain, a recognized producer of fumonisins. Field experiments were performed in 2006 and 2007 in two sites in NW Italy to determine the effects of the timing of insecticide application on ECB damage, fungal ear rot and fumonisin contamination under natural conditions. Different insecticide application timings were compared, from maize flowering to approximately 15 days after the flight peak of adult ECB. At harvest, the ears were rated for incidence and severity of ECB damage, fungal ear rot symptoms and fumonisin (FB1 + FB2) contamination. In all years/sites, treatments applied at the beginning of consistent ECB flight activity were most effective in controlling insect damage on ears. Fungal ear rot and fumonisin contamination were significantly affected by ECB control. The efficacy of the best timing of insecticide application in controlling fumonisin contamination was, on average, 93% compared to the untreated control. Contamination levels of these mycotoxins increased with either an earlier or later treatment. Furthermore, an earlier insecticide application showed lower fumonisin contamination than a treatment applied after the adult flight peak. Production of maize kernels and maize-based foods that do not exceed the maximum international and EU permitted levels for fumonisins could be enhanced by appropriate insecticide treatment against second generation ECB. The optimum time for insecticide application is between the beginning of consistent adult flight activity and the flight peak.