Wholegrain triticale sourdough: Effects of triticale:Wheat flour ratio and hydration level on bread quality.

Triticale (×Triticosecale) is a hybrid between wheat (Triticum spp.) and rye (Secale cereale), producing higher grain yields than wheat in challenging environments. Triticale grain is also highly nutritious. Thus, the potential of triticale grain for an expanded range of food applications should be explored. Sourdough bread has unique functional and nutritional properties, but understanding the effects of partial substitution of triticale for wheat flour and varying levels of dough moisture content on sourdough quality requires further research. The aim of this study was to evaluate the wholegrain flour of contrasting triticale cultivars in comparison to that of a common wheat cultivar in commercial sourdough breadmaking. Two triticale cultivars (Goanna and Hawkeye, selected from a panel of Australian genotypes) and one wheat cultivar (Scout) were grown in a field trial in northern NSW, Australia. Differences in quantitative texture and color parameters of the dough and sourdough bread resulting from (1) substitution of commercial wholemeal wheat flour with different proportions of wholegrain triticale or wholegrain wheat (Scout) flour (0%, 60%, 70%, 80%, and 90%) and (2) varying the amount of water included in the dough preparation (70%, 80%, 90%, and 100 g water/100 g flour) were determined. Replacement of wholemeal wheat flour with 60% wholegrain Goanna flour (protein content 12.76%; c.f. 11.50% for Hawkeye, 12.40% for Scout), and addition of 100 g water/100 g flour in the dough preparation gave the highest quality sourdough bread based on specific volume, texture, and color parameters and had similar properties to the control made from wheat alone.

Indigenous Australian grass seeds as grains: macrostructure, microstructure and histochemistry.

Utilization of grains of local grasses by Australia's First Nations people for food and connection to Country has largely been lost due to colonization. Native Australian grain production has the potential to deliver environmental, economic, nutritional and cultural benefits to First Nations people and the wider community. Revitalization of the native grain food system can only be achieved if relevant properties of the grains are elucidated. This study aimed to characterize the grain structure and histochemistry of four Australian native grasses: Dactyloctenium radulans (Button Grass), Astrebla lappacea (Curly Mitchell Grass), Panicum decompositum (Native Millet) and Microlaena stipoides (Weeping Grass). For these species, as well as wheat and sorghum, whole-grain images were obtained via stereo microscopy, starch and the embryo were visualized, and sections of fixed grains were imaged via bright-field and fluorescence microscopy. The shape, size and colour of the whole native grains varied between the species. The aleurone layer was one-cell thick in the native species, as in the domesticated grains, except for Weeping Grass, which had a two-cell-thick aleurone. In the native grains, endosperm cell walls appeared thinner than in wheat and sorghum. Starch granules in Button Grass, Curly Mitchell Grass and Native Millet were found mainly in the central region of the starchy endosperm, with very few granules in the sub-aleurone layer, whereas Weeping Grass had abundant starch in the sub-aleurone. Protein appeared most abundant in the aleurone and sub-aleurone layers of the native grains, although in Button Grass, the starchy endosperm was observed to be rich in protein, as in wheat and sorghum. As a proportion of the whole grain, the embryo was larger in the native species than in wheat. The differences found in the grain properties among the four native Australian species have important implications for the agri-food industry in a changing climate.

Panicum decompositum, an Australian Native Grass, Has Strong Potential as a Novel Grain in the Modern Food Market.

Native Millet (Panicum decompositum) is a native grass species that was used as a staple food by many Australian Aboriginal communities. In this study, the potential for using Native Millet (NM) as a novel flour in the modern food market was investigated. Intact grain and white and wholemeal flours from two populations of NM were compared to bread wheat cv. Spitfire (SW) using a range of physical and chemical tests. The baking properties of NM flour were assessed using basic flatbreads made with 25:75 and 50:50 (NM:SW) mixes of wholemeal flour with 100% SW wholemeal flour used as the control. The grain size of NM was found to be smaller than SW. Milling yield, defined as the proportion of flour obtained from a whole seed, for NM was 4-10% lower than SW under the same moisture conditions used for tempering (drying) wheat. The properties of wholemeal flour indicated that NM flour has lower viscosity and low flour pasting ability compared to SW. This is likely due to the low starch content and high fibre content of NM seed. Wholemeal flour derived from NM had a protein content of 13.6% compared to 12.1% for SW. Based on a sensory analysis using an untrained panel, the distinct colour and texture may negatively affect the acceptance of NM flour by the consumer, but taste and aroma was not found to differ among samples. There were strong indications that the novelty of NM flour may help outweigh any limitations to consumer acceptance, making it a valuable product in future food markets.

The genetics of vigour-related traits in chickpea (Cicer arietinum L.): insights from genomic data.

KEY MESSAGE: QTL controlling vigour and related traits were identified in a chickpea RIL population and validated in diverse sets of germplasm. Robust KASP markers were developed for marker-assisted selection. To understand the genetic constitution of vigour in chickpea (Cicer arietinum L.), genomic data from a bi-parental population and multiple diversity panels were used to identify QTL, sequence-level haplotypes and genetic markers associated with vigour-related traits in Australian environments. Using 182 Recombinant Inbred Lines (RILs) derived from a cross between two desi varieties, Rupali and Genesis836, vigour QTL independent of flowering time were identified on chromosomes (Ca) 1, 3 and 4 with genotypic variance explained (GVE) ranging from 7.1 to 28.8%. Haplotype analysis, association analysis and graphical genotyping of whole-genome re-sequencing data of two diversity panels consisting of Australian and Indian genotypes and an ICRISAT Chickpea Reference Set revealed a deletion in the FTa1-FTa2-FTc gene cluster of Ca3 significantly associated with vigour and flowering time. Across the RIL population and diversity panels, the impact of the deletion was consistent for vigour but not flowering time. Vigour-related QTL on Ca4 co-located with a QTL for seed size in Rupali/Genesis836 (GVE = 61.3%). Using SNPs from this region, we developed and validated gene-based KASP markers across different panels. Two markers were developed for a gene on Ca1, myo -inositol monophosphatase (CaIMP), previously proposed to control seed size, seed germination and seedling growth in chickpea. While associated with vigour in the diversity panels, neither the markers nor broader haplotype linked to CaIMP was polymorphic in Rupali/Genesis836. Importantly, vigour appears to be controlled by different sets of QTL across time and with components which are independent from phenology.

Characteristics of modern triticale quality: glutenin and secalin subunit composition and mixograph properties.

Triticale is a hardy, high yielding cereal crop with a reputation for poor gluten strength. The secalogluten formation capacity was investigated in 17 modern triticale cultivars by defining their HMW glutenin and 75K γ-secalin alleles and then assessing SDS-sedimentation height and mixograph parameters in a subset of cultivars. The allelic diversity was poor with only 13 alleles identified at four loci; nevertheless, sufficient variability existed to allow secalogluten improvement through crossbreeding and selection. SDS-sedimentation height of triticale (35.5 mm) and mixing time (2.7 min) was equivalent to soft wheat but significantly less than hard wheat. However, flour protein content was 16% less in triticale compared to wheat, despite similar grain protein contents, suggesting triticale stores a lower proportion of grain protein in the endosperm. The confounding factor of protein content must be considered as part of an equitable analysis of gluten quality in cultivar breeding, in the interpretation of previous triticale research, and when comparing triticale to wheat. Improved glutenin properties will expand the utility of triticale in human food products and, thus, increase potential profitability.