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Summary The aim of this study was to determine wheat constituents in bread and pasta that might result in intestinal gas production. Fructans, water‐soluble arabinoxylans, arabinogalactan proteins and fermentable sugars were followed in bread and pasta made with ancient (Khorasan wheat; emmer) and modern wheats (common wheat; durum). After fermentation for 180 min, 80% of fructans were eliminated and higher levels of fructose than glucose accumulated in bread dough supplemented with sucrose. Whole‐grain Khorasan wheat and emmer flours inhibited yeast fermentative activity. Half of fructans, arabinogalactan proteins and sugars were washed out in cooking water for pasta. Water‐soluble wheat arabinoxylans increased in bread and cooked pasta. With very low levels (0.3–0.8%, dry basis), fructans in cooked pasta and, in particular, long‐fermentation bread prepared with modern or ancient wheat would unlikely act as major gas‐forming triggers of gastrointestinal discomfort associated with noncoeliac gluten sensitivity.

Persons suffering from celiac disease (CD) must avoid foods containing gluten or those contaminated with wheat, barley, or rye. This study was designed to estimate gluten contamination of cereal-based foods available in Canada, whether labelled gluten-free or not. About half of the 148 foods sampled were labelled as gluten-free. According to R5-enzyme-linked immunosorbent assay (ELISA), twenty-three cereal-based foods (or 15%) contained more than 20 mg of gluten per kg, including sixteen regular and seven gluten-free foods, the latter being the least contaminated. When used in combination with R5-ELISA, AOAC-ELISA (not detecting barley) was a simple and efficient tool to roughly estimate the nature of the gluten contamination, which was later confirmed by real-time polymerase chain reaction for barley, and wheat ⁄ barley ⁄ rice. Rice-, corn-or quinoa-based foods were the safest for celiac patients. In addition to misleading food labelling for both gluten-rich and gluten-free foods, critical issues for persons with CD included foods made with oats or buckwheat (contaminated with wheat and barley gluten) in addition to those, such as breakfast cereals, specifically enriched with barley malt ingredients.

To replace benzoyl peroxide as a bread dough‐bleaching agent, pure and commercial oxido‐reductases (peroxidases, catalases, glucose oxidases, lipoxygenase, and laccase) were screened based on degradation of β‐carotene in a liquid system (5 μg of β‐carotene/mL of 0.1M citrate phosphate buffer at pH 5.5 or 6.5) or dough. Peroxidases had the best bleaching activity; some catalases also showed bleaching potential in a liquid system but not in bread dough, suggesting that screening enzymes in liquid media has limited application for dough. In 100 g of flour, combinations of peroxidase (3,000 U), lipase (815–1,630 U), and linoleic acid (0–300 mg) completely bleached bread dough.

Summary The aim of this study was to determine the effects of wheat preharvest application of a glyphosate‐based herbicide (Roundup WeatherMax® with Transorb® 2 Technology) on whole‐grain flour composition and properties, including yeast activity. The effect of dough fermentation on the degradation of herbicide residues was also estimated. Grain samples from two hard red spring wheat varieties exceeded the maximum residue limits (5 mg kg−1) in Canada. Glyphosate had minor effects on wheat kernels composition and properties, including fructans content and yeast gassing power. No degradation of Roundup® or pure glyphosate was seen after dough fermentation for up to 4 h and baking. These results call for more scientific studies on glyphosate residues in wheat.