Durum wheat (Triticum turgidum ssp. durum) is typically used to produce pasta. In some parts of the world, it is used to make bread but with inferior loaf volume and texture compared with common wheat bread. This study describes the effect on technological properties of pasta and bread made from durum wheat cv. Svevo (recurrent parent (S), HMW-GS null, 7+8) and two isogenic genotypes carrying pairs of additional subunits 5+10 (S 5+10) or 2+12 (S 2+12), normally present at the Glu-D1 locus in bread wheat. The semolina was re-ground to flour, mixed in various proportions with bakers flour and used to prepare loaves. The dough properties of the S 5+10 line were markedly different from Svevo, having over-strong, stable dough, low wet gluten and elasticity; S 2+12 also displayed stronger dough. Pasta prepared from these genotypes showed lower cooked firmness (adjusted for protein differences), ranked Svevo > S 5+10 = S 2+12. There were no other differences in pasta cooking quality. Bread loaf volume and loaf score decreased as more bakers flour was replaced by durum flour, but the decline varied with the genetic material and dosage. The greatest reduction in loaf volume occurred using S 5+10 and the least with S 2+12, which was similar to Svevo. Bake score was reduced with S 5+10 only. The best loaf was made using Svevo. This work shows that it is possible to manipulate the processing properties of pasta and durum–bread-wheat blends by altering the glutenin subunit composition. This represents an efficient tool to finely manipulate gluten quality in durum wheat.

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Background and objectives Durum wheat is used to make leavened bread; however, durum bread has inferior loaf volume, structure, and texture compared to bread made from common wheat. One approach to overcome this is to transfer key storage protein genes present at the Glu‐D1 locus from bread wheat into durum. Durum wheat Svevo missing Glu‐B1subunits 7 + 8 and Lira biotypes with low molecular weight glutenin subunits types 1 and 2 were evaluated for their breadmaking potential with and without high molecular weight glutenin subunits 2 + 12 or 5 + 10. Findings Bread made from blends of durum and a commercial baker's flour (10%, 25%, 50% w/w) assessed over two seasons in 10 different genotypes showed that as more durum was included in the mixture, loaf volume and texture score declined. Incorporation of the 2 + 12 subunit pair in the genotypes Lira42 and Lira45 improved bread quality but not in Svevo, whereas including 5 + 10 improved bread quality of Lira42 had no effect on Lira45 but reduced quality of Svevo. Low amylose Svevo had similar loaf quality to Svevo while adding 5 + 10 had minimal impact except at 50% with a small improvement in loaf quality. Bread stored up to 7 days became firmer partly due to increased starch retrogradation, and loaves were similar to bread made from baker's flour. Low amylose Svevo kept the loaf fresher but only up to 3 days of storage. Subunit pair 5 + 10 made the loaf firmer after 7 days compared to control. Conclusions Addition of the 2 + 12 or 5 + 10 benefited the weaker type gluten as found in Lira 42 (LMW‐1, HMW 20) but not with stronger dough in Svevo even in the absence of HMW 7 + 8. It appears that while Glu‐D1 subunits are critical for good breadmaking in hexaploid wheat, they appear to have limited value in improving loaf volume and structure in durum bread. Significance and novelty Some improvements in bread quality can be obtained by introducing genes coding for Glu‐D1subunits 2 + 12 and 5 + 10 in durum wheat depending on the genotype, especially weak dough types, and the results presented comprise the first report of such effect.

We report the isolation of a pure form of cell walls from wheat endosperm 'popped' out from the whole, enzyme deactivated and soaked grain, and compare them with cell walls isolated from milled flours of extraction rates from 45% to 75%, at physiological (37 °C) and elevated (70 °C) temperatures. Cell walls isolated from flours all contained non-endosperm walls whereas walls from popped endosperm were apparently pure. The monosaccharide composition of 'popped' cell walls was different to that of cell walls isolated from flour, particularly glucose and mannose contents (34 and 7 % for 'popped' cf 29 and 3% for flour respectively) and arabinose to xylose ratios (0.45 for 'popped' cf 0.58 for flour). Total phenolic content of popped endosperm cell walls were three to four times lower than for cell walls from flour. Elevated isolation temperature also had a solubilising effect, altering the cell wall composition. This study provides a novel method of isolating pure wheat endosperm cell walls, and demonstrates how contaminating (thick cell walled) nonendospermic material in milled flours can have a major influence on cell wall compositional analyses.

Background and objectives Heat stress is a major limiting factor to wheat yield that also impacts on grain quality, and its incidence is likely to increase. Thirty‐seven durum wheats were grown in irrigated replicated field trials over two seasons in Australia, normal sown (NS) or a 2‐month late sown (LS). Agronomic and technological quality traits were examined. Findings Later sowing exposed the crop to more days at temperatures of 30°C and above indicating more heat stress while the irrigation ensured no drought stress. Relative to NS, LS reduced yield, grain weight, test weight, and milling yield but grain vitreousness and hardness either increased or decreased depending on the trial. However, LS had positive effects on increasing protein content, dough quality indicators, and increased the proportion of high molecular weight gluten polymer. LS also enhanced pasta end‐use traits, increasing pasta yellowness and firmness and decreasing cooking loss. Genotypes that showed relatively stable yield and grain characteristics under LS were identified (Caparoi, Jandaroi, Kalka, Kronos, Saintly, and WID802). Conclusions These findings suggest that the heat stress experienced enhanced dough and pasta quality, despite having a negative impact on yield and physical grain characteristics. Genotypes were identified that represent potential sources of heat tolerance that could be useful in breeding to help limit the undesirable effects of heat stress on durum production. Significance and novelty Late sowing of wheat is a good strategy to obtain exposure to heat stress in the Australian environment and can be used to select genotypes with better yield and quality stability.

Lupin is an economical source of protein, fibre and bioactive compounds, and to obtain these health and nutritional benefits lupin flour has been used in bread production. However, addition of more than 10% lupin flour markedly reduces bread quality mainly due to gluten dilution. The main aim of this research was to retain lupin bread quality enriched with higher percentages of lupin flour (20%) by addition of vital gluten powder (0%, 2%, 3.5% and 5%), investigating the effects of lupin variety (Lupinus albus and L. angustifolius) and two baking systems (rapid and sponge & dough). Impact on bread staling qualities was also determined through texture analysis of samples over a 72-h storage period. Compared to lupin bread with nil gluten addition, significant improvements in loaf volume and crumb texture were observed with addition of gluten powder especially at 5% which increased loaf volume by an average of 20% across lupin sources and baking methods, and crumb softness by 30-50%. Differences were observed between the lupin flour sources. L. angustifolius had a reduced weakening effect when blended with the base flour compared with L. albus. The Sponge & Dough process was found to be more suitable to the inclusion of lupin flour than the rapid process.

Wheat bran is a conventional by-product of the wheat milling industry mainly used for animal feed. It is a rich and inexpensive source of phytonutrients, so is in demand for fibre-rich food products but creates quality issues when incorporated into bread. The purpose of this study was to characterize the physicochemical properties and phytochemical composition of different size durum bran fractions and show how they impact bread quality. Durum wheat (Triticum durum Desf.) was milled to create a coarse bran fraction (CB), which was further ground into a finer fraction (FB) which was sieved using four screens with apertures 425, 315, 250, 180, and <180 µm to create a particle size range of 1497 to 115 µm. All fractions contained phytosterol with highest in the 180 and FB, while total phenolic acids and antioxidant capacity was highest in CB and 425. Use of the fractions in a leavened common wheat (T. aestivum L.) bread formula at 10% incorporation negatively impacted bread loaf volume, colour, and texture compared to standard loaves, with CB having the least impact. Results suggest that to combine the highest phytochemical content with minimal impact on bread quality, bran particle size should be considered, with CB being the best choice.

Cereal Chem. 93(5):482-486There is no information on the effect of sulfuryl fluoride (SF) on durum wheat technological properties and products made from fumigated durum wheat. Durum wheat and semolina were exposed to a range of SF applications under conditions that might be typically encountered in bulk storage facilities used in many countries. SF greatly reduced the germination percentage of fumigated durum wheat, with increasing impact under higher SF concentration, grain moisture content, and fumigation temperature. SF greatly reduced seed germination percentage, impacting more the higher the SF concentration. SF had little to no effect on grain test weight, 1,000-grain weight, hardness, protein content, semolina ash content, and mixograph properties. At the highest SF concentration (31.25 mg/L for 48 h) there was a tendency for pasta cooking loss to be increased but still acceptable, and other pasta properties were largely unaffected. Fumigation with SF did not have any impact on the baking properties of a wholemeal durum flour-commercial flour mix. Therefore, SF is not recommended if the grains are to be used as seeds for agricultural production, but for the production of semolina, pasta, and bread, SF used under typical fumigation conditions has little to no impact on technological properties of durum wheat.