Sequential pyrolysis and catalytic low temperature reforming of wheat straw

Aim of the work is the implementation of a low temperature reforming (LT reforming) unit downstream the Haloclean pyrolyser in order to enhance the heating value of the pyrolysis gas. Outside the focus of this work was to gain a synthesis gas quality for further use. Temperatures between 400 °C and 500 °C were applied. A commercial pre-reforming catalyst on a nickel basis from Südchemie was chosen for LT reforming. As biogenic feedstock wheat straw has been used. Pyrolysis of wheat straw at 450 °C by means of Haloclean pyrolysis leads to 28% of char, 50% of condensate and 22% of gas. The condensate separates in a water phase and an organic phase. The organic phase is liquid, but contains viscous compounds. These compounds could underlay aging and could lead to solid tars which can cause post processing problems. Therefore, the implementation of a catalytic reformer is not only of interest from an energetic point of view, it is generally interesting for tar conversion purposes after pyrolysis applications. By using a fixed bed reforming unit at 450–490 °C and space velocities about 3000 l/h the pyrolysis gas volume flow could be increased to about 58%. This corresponds to a decrease of the yields of condensates by means of catalysis up to 17%, the yield of char remains unchanged, since pyrolysis conditions are the same. The heating value in the pyrolysis gas could be increased by the factor of 1.64. Hydrogen concentrations up to 14% could be realised.

Application of mint and cinamon against Fusarium disease of winter wheat

In our study the application of mint species (spearmint, peppermint ‘Mitcham’ and peppermint ‘Mexian’) and cinnamon was investigated against Fusarium head blight of winter wheat in vitro and in vivo. The effect of crude drugs and the aqueous extract of mint, and the effect of essential oils of mint and cinnamon on mycelial growth were evaluated in lab. On artificial media the crude drug showed higher inhibition than aqueous plant extracts. Cinnamon and spearmint oils e.ectively inhibited mycelia growth. In field trial artificially inoculated winter wheat was treated with the in vitro effective oils under small-plot conditions. The disease incidence was most inhibited by cinnamon oil, applied curative. According to our results the essential oil of cinnamon can be an appropriate candidate for the research of alternative disease control.

Wheat bran promotes enrichment within the human colonic microbiota of butyrate-producing bacteria that release ferulic acid

This article is protected by copyright. All rights reserved. Acknowledgements: The authors acknowledge support from the Scottish Government Food Land and People programme (RESAS). We would like to thank Lorraine Scobbie and Gary Duncan for technical support. Funding for JP, AWW and 454 pyrosequencing was provided by the Wellcome Trust (grant number 098051).

Availability and dose response of phytophenols from a wheat bran-rich cereal product in healthy human volunteers

Funding: Kellogg’s and the Scottish Government Food Land and People Programme.

Fundamental studies of the application of wheat for malting and brewing

Wheat (Triticum aestivum L.) has a long tradition as a raw material for the production of malt and beer. While breeding and cultivation efforts for barley have been highly successful in creating agronomically and brew- technical optimal specialty cultivars that have become well established as brewing barley varieties, the picture is completely different for brewing wheat. An increasing wheat beer demand results in a rising amount of raw material. Wheat has been - and still is – grown almost exclusively for the baking industry. It is this high demand that defines most of the wheat breeding objectives; and these objectives are generally not favourable in brewing industry. It is of major interest to screen wheat varieties for brewing processability and to give more focus to wheat as a brewing cereal. To obtain fast and reliable predications about the suitability of wheat cultivars a new mathematical method was developed in this work. The method allows a selection based on generally accepted quality characteristics. As selection criteria the parameters raw protein, soluble nitrogen, Kolbach index, extract and viscosity were chosen. During a triannual cultivation series, wheat varieties were evaluated on their suitability for brewing as well as stability to environmental conditions. To gain a fundamental understanding of the complex malting process, microstructural changes were evaluated and visualized by confocal laser scanning and scanning electron microscopy. Furthermore, changes observed in the micrographs were verified and endorsed by metabolic changes using established malt attributes. The degradation and formation of proteins during malting is essential for the final beer quality. To visualise fundamental protein changes taking place during malting, samples of each single process step were analysed and fractioned according their solubility. Protein fractions were analysed using a Lab-on-a-chip technique as well as OFFgel analysis. In general, a different protein distribution of wheat compared to barley or oat could be confirmed. During the malting process a degradation of proteins to small peptides and amino acids could be observed in all four Osborn fractions. Furthermore, in this study a protein profiling was performed to evaluate changes during the mashing process as well as the influence of grist composition. Differences in specific protein peaks and profile were detected for all samples during mashing. This study investigated the suitability of wheat for malting and brewing industry and closed the scientifical gap of amylolytic, cytolytic and proteolytic changes during malting and mashing.

Reduction of salt in yeasted wheat bread: impact on bread quality and solutions using sourdough fermented by functional lactic acid bacteria strains

The dietary intake of sodium chloride has increased considerably over the last few decades due to changes in the human diet. This higher intake has been linked to a number of diseases including hypertension and other cardiovascular diseases. Numerous international health agencies, as well as the food industry, have now recommended a salt intake level of 5-6 g daily, approximately half of the average current daily intake level. Cereal products, and in particular bread, are a major source of salt in the Western diet. Therefore, any reduction in the level of salt in bread could have a major impact on global health. However, salt is a critical ingredient in bread production, and its reduction can have a deleterious effect on the production process as well as on the final bread quality characteristics such as shelf-life, bread volume and sensory characteristics, all deviating from the bakers’ and consumers’ expectations. This work addresses the feasibility of NaCl reduction in wheat bread focusing on options to compensate NaCl with the use of functional sourdoughs. Three strains were used for the application of low-salt bread; L. amylovorus DSM19280, W. cibaria MG1 and L. reuteri FF2hh2. The multifunctional strain L. reuteri FF2hh2 was tested the first time and its application could be demonstrated successfully. The functionalities were based on the production of exopolysaccharides as well as the production of antifungal compounds. While the exopolysaccharides, mainly high molecular dextrans, positively influenced mainly bread loaf volume, crumb structure and staling rate, the strains producing antifungal compounds prolonged the microbial shelf life significantly and compensated the lack of salt. The impact on the sensory characteristics of bread were evaluated by descriptive sensory evaluation. The increase in surface area as well as the presence of organic acids impacted significantly on the flavour profile of the sourdough bread samples. The flavour attribute “salt” could be enhanced by sourdough addition and increased the salty perception. Furthermore, a trained sensory panel evaluated for the first time the impact of yeast activity, based on different salt and yeast concentrations, on the volatile aroma profile of bread crumb samples. The analytical measurements using high resolution gas chromatography and proton-transfer-reaction mass spectrometry (PTR-MS) resulted in significantly different results based on different yeast activities. Nevertheless, the extent of the result could not be recognised by the sensory panel analysing the odour profile of the bread crumb samples. Hence, the consumer cannot recognised low-salt bread by its odour. The use of sourdough is a natural option to overcome the broad range of technological issues caused by salt reduction and also a more popular alternative compared to existing chemical salt replacers.

Markers for seedling and adult plant crown rot resistance in four partially resistant bread wheat sources

QTL identified for seedling and adult plant crown rot resistance in four partially resistant hexaploid wheat sources. PCR-based markers identified for use in marker-assisted selection. Crown rot, caused by Fusarium pseudograminearum, is an important disease of wheat in many wheat-growing regions globally. Complete resistance to infection by F. pseudograminearum has not been observed in a wheat host, but germplasm with partial resistance to this pathogen has been identified. The partially resistant wheat hexaploid germplasm sources 2-49, Sunco, IRN497 and CPI133817 were investigated in both seedling and adult plant field trials to identify markers associated with the resistance which could be used in marker-assisted selection programs. Thirteen different quantitative trait loci (QTL) conditioning crown rot resistance were identified in the four different sources. Some QTL were only observed in seedling trials whereas others appeared to be adult plant specific. For example while the QTL on chromosomes 1AS, 1BS, and 4BS contributed by 2-49 and on 2BS contributed by Sunco were detected in both seedling and field trials, the QTL on 1DL present in 2-49 and the QTL on 3BL in IRN497 were only detected in seedling trials. Genetic correlations between field trials of the same population were strong, as were correlations between seedling trials of the same population. Low to moderate correlations were observed between seedling and field trials. Flanking markers, most of which are less than 10 cM apart, have now been identified for each of the regions associated with crown rot resistance.

Does Fumigation of Durum Wheat and Semolina with Sulfuryl Fluoride affect Quality of the Grain, Semolina and derived Spaghetti and Bread?

There 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 effects on grain test weight, 1000 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 while 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.

A review of weed management in wheat using crop competition

Wheat occupies a principal place in the diet of humans globally, contributing more to our daily calorie and protein intake than any other crop. For this reason, preventing weed induced yield losses in wheat has high significance for world food sustainability. Herbicides and tillage play an important role in weed control, but their use has often unacceptable consequences for humans and the wider environment. Additionally, the range of herbicides effective on key weeds is dwindling due to the evolution of herbicide resistance. Elevating crop competitiveness against weeds, through a combination of wheat breeding and innovative planting design (planting density, row spacing and orientation), has strong potential to reduce weed-induced yield losses in wheat. The last decade of research has provided a solid foundation for the breeding of weed suppressive wheat cultivars, and continued research in this area should be a focus for the future. In the interim, there is cause for optimism that weeds can be effectively suppressed using existing wheat varieties, through careful cultivar selection and choice of planting design. Further research is required to define the nature of relationships between cultivar traits and competitive planting strategies, across diverse weed flora in multiple countries, sites and seasons. Investment in such innovation promises to produce benefits, not only in terms of sustained wheat yields, but also in terms of human and ecosystem health, through ameliorating chemical and sediment contamination, soil degradation, and CO2 pollution.

Optimised wheat root architecture for increased yield and yield stability in the face of a changing climate.

This project provided information, selection techniques and strategies to facilitate the development of high-yielding, stay-green wheat varieties for Australian growers through: a) Improved understanding of the relationships between seminal root traits and other root- and shoot-related traits in determining high-yielding, stay-green phenotypes. b). Molecular markers and rapid phenotypic screening methods that allow selection in breeding programs and identification of genetic regions controlling favourable traits. c). Identification of traits leading to high-yielding, stay-green phenotypes for particular target populations of environments using computer simulation studies.

Herbicides cross resistance of a multiple resistant short-awn foxtail ( Alopecurus aequalis Sobol.) population in wheat field

Alopecurus aequalis Sobol. is a common grass weed, which has become increasingly troublesome to control in China wheat fields. One A. aequalis population, collected from Anhui Province China, was suspected to be resistant to fenoxaprop-P-ethyl and mesosulfuron-methyl. This study aimed to establish the cross-resistance pattern using the purified subpopulation and explore the potential targetsite and non-target-site based resistance mechanisms. Sequencing results showed that a single nucleotide change of ATT to AAT was present in acetyl-CoA carboxylase (ACCase) gene of the resistant (R) plants, resulting in an Ile2041Asn amino acid substitution. Besides, another single nucleotide change of CCC to CGC was present in acetolactate synthase (ALS) gene of the R plants, resulting in a Pro197Arg amino acid substitution. The homozygous resistant plants were isolated and the seeds were used in whole-plant herbicide bioassays. Compared with the susceptible (S) population, R population displayed high level resistance to fenoxaprop-P-ethyl and mesosulfuronmethyl. Cross resistance patterns showed that the R population was highly resistant to clodinafop-propargyl, moderately resistant to pyroxsulam and flucarbazoncsodium, lowly resistant to pinoxaden, and susceptible to tralkoxydim, sethoxydim, and isoproturon. The pretreatment of piperonyl butoxide reduced the 50% growth reduction (GR50) value of fenoxaprop-P-ethyl, suggesting that target-site resistance and non-target-site resistance mechanisms were both present in fenoxaprop- P-ethyl-resistance of A. aequalis. This is the first report of ACCase Ile2041Asn and ALS Pro197Arg mutation in A. aequalis.