Effect of debranning process on deoxynivalenol content in whole‐wheat flours

Wheat debranning: effects on mycotoxins, phenolic content, and antioxidant activity

The debranning process, at an industrial scale, was applied to grains of two wheat cultivars to determine its effect on Fusarium mycotoxin content and antioxidant activity. Grain samples from the BRS Marcante and BRS Reponte wheat cultivars, naturally contaminated by Fusarium, were used in the study. The dry wheat samples were processed on the polisher once or twice and evaluated by hardness index, chemical composition (moisture, protein, and ash), deoxynivalenol (DON) and zearalenone (ZON) levels, phenolic content, and antioxidant activity. In the BRS Marcante cultivar, the debranning process only slightly reduced the DON and ZON contents in whole-wheat flours compared with the previous cleaning treatment (no-debranned). In the BRS Reponte cultivar, the DON concentration decreased by 36% at a debranning ratio of 5%, obtained by polishing, compared with prior cleaning treatment (no-debranned). In addition, the polishing reduced the ZON level by 56% compared with the cleaned wheat. The debranning process did not reduce the antioxidant capacity. Therefore, debranning is a suitable technology to obtain safer and healthier food by minimizing the mycotoxin content and retaining antioxidant capacity.

Lipid Process Markers of Durum Wheat Debranning Fractions

At present, whole grains are usually obtained by adding bran and middlings to refined flours, and this recombination leads to certain variations in the ratio of endosperm, bran and germ, resulting in flours with very different compositional characteristics and rheological properties. Therefore, this study focuses on the identification of specific lipid markers in different debranning fractions of Italian and Canadian durum wheat blends. The by-products obtained from five different debranning levels (3, 6, 9, 12 and 15%) had a high content of monounsaturated fatty acids and a higher concentration of tocopherols and sterols than the corresponding debranned grains. The Italian and Canadian durum wheat samples did not show significant differences in the content of these bioactive lipid compounds. In particular, palmitic acid, oleic acid, tocopherol isomers and total sterols could be useful biomarkers for evaluating the grain-to-tissue ratio in recombined flours.

Use of Air-Classification Technology to Manage Mycotoxin and Arsenic Contaminations in Durum Wheat-Derived Products

Mycotoxins are the most common natural contaminants and include different types of organic compounds, such as deoxynivalenol (DON) and T-2 and HT-2 toxins. The major toxic inorganic elements include those commonly known as heavy metals, such as cadmium, nickel, and lead, and other minerals such as arsenic. In this study, micronisation and air classification technologies were applied to durum wheat (Triticum turgidum ssp. durum L.) samples to mitigate inorganic (arsenic) and organic contaminants in unrefined milling fractions and final products (pasta). The results showed the suitability of milling plants, providing less refined milling products for lowering amounts of mycotoxins (DON and the sum of T-2 and HT-2 toxins) and toxic inorganic elements (As, Cd, Ni, and Pb). The results showed an As content (in end products) similar to that obtained using semolina as raw material. In samples showing high organic contamination, the contamination rate detected in the more bran-enriched fractions ranged from 74% to 150% (DON) and from 119% to 151% (sum of T2 and HT-2 toxins) as compared to the micronised samples. Therefore, this technology may be useful for manufacturing unrefined products with reduced levels of organic and inorganic contaminants, minimising the health risk to consumers.

Traditional and Non-Conventional Pasta-Making Processes: Effect on In Vitro Starch Digestibility

Pasta is a carbohydrate-rich food with a low glycemic index (GI) and is one of the main sources of slowly digestible starch (SDS). The presence of bran fractions (BFs) in pasta may enhance its health potential, owing to the content of fiber, micronutrients, and bioactive compounds; however, at the same time, BF may affect starch digestibility. In this study, the bioaccessibility of starch in pasta made with BF-enriched semolina (BF pasta), or only with micronized debranned kernel (DK pasta), and a control pasta made with traditional semolina was evaluated by applying two different in vitro models. The control pasta showed a percentage of SDS about four-fold higher than that of the BF pasta and 1.5-fold higher than that of the DK pasta (p < 0.05). The amount of starch released during simulated gastrointestinal digestion was slightly lower, but not significantly different, for the control pasta than for both the BF and DK pasta. These results suggest that the presence of a higher amount of dietary fiber in BF pasta can affect the structure of the food matrix, interfering with the formation of the gluten network, water absorption, and starch granule accessibility, while micronization could enhance starch digestibility due to starch gelatinization. These findings emphasize the need to optimize the process for producing fiber-rich pasta without affecting its low starch digestibility and, consequently, its GI.