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BACKGROUND AND OBJECTIVES: Lentil (Lens culinaris M.) is a high value, highly nutritional grain which originated in Middle‐East. More recently lentil has gained favor in Western countries due to the high value in production and the benefits they provide agronomically; however, growing lentil in countries such as Australia, Canada, and the United States is not without its challenges. One is the high probability of damage due to radiant frost either before flowering or during pod‐filling. The effects of which is most noticeable in the appearance of the seed reduce the value and usability of crops. On the other hand, a generation of well informed, health‐conscious, and environmentally concerned consumers has driven the demand for affordable and healthy food alternatives. Such demand has resulted in a growing industry for protein extraction and novel food production. If used for protein extraction or novel food production, the visual appearance of seeds is no longer an important quality trait. Lentil seeds damaged through frost that still retain a high nutritional composition may be the perfect candidate for a low‐cost substrate in novel food production while improving the outcomes for growers and industry alike. FINDINGS: This study used as a model extrusion technology to investigate the use of flour derived from Grade 1 (premium quality) and downgraded frost‐damaged lentil and to monitor compositional changes during extrusion. The study concentrated on how total protein, individual carbohydrates, and phenolic acids changed through high‐temperature, high‐pressure extrusion. Overall flours made from composite lentil–wheat flour had significantly higher concentrations of protein and carbohydrates than the base wheat flour. No significant differences were observed for total protein or carbohydrates between Grade 1 and frost‐damaged flours; however, extrusion significantly reduced total protein concentration as well as maltose and glucose concentration but did not alter th

The effects of elevated concentrations of atmospheric CO₂ (e[CO₂]) on the nutritive value of wheat vegetative matter and grain as a feedstock for ruminants were investigated in a study undertaken at the Australian grains free‐air CO₂ enrichment (AGFACE) facility. The study included two commercial wheat cultivars (Janz and Yitpi) and two genetic selections from a Seri/Babex population (SB003 and SB062) which had previously been characterised for low and high water‐soluble carbohydrate accumulation efficiency. The trial was grown under ambient (~390 µmol/mol) and elevated (~550 µmol/mol) CO₂ conditions, and plants harvested at tillering, anthesis and physiological maturity. Composition analyses to determine the nutritive value for ruminant feed were undertaken on stems, leaves and grain. Plant and grain nitrogen were reduced in the e[CO₂] treatments, and as expected, the water‐soluble carbohydrates increased. All genotypes responded to e[CO₂] with the effects of altered composition evident within 60 days of sowing. Determinants of ruminant feed quality such as neutral and acid detergent fibre and estimated in vitro metabolisable energy were not significantly affected. The reduced plant and grain N will impact on the nutritive value and supplementation may be required. The impact of e[CO₂] on chemical composition of wheat plants may be greater if the predicted climate change is associated with concomitant abiotic stress such as high ambient temperature or low soil moisture.

Post-harvest change in the colour of green field pea (Pisum sativum L.) is undesirable as this impacts the visual quality and market value of the seed. To date, there is no standard, objective method to determine bleaching. Therefore, the aim of this study was to develop an objective method for scoring bleaching based on colour reflectance spectra, measured both by spectrophotometer and multispectral Image Analysis (IA). Green field pea seeds were sorted into samples of uniform colour and these were used to train the model. Spectra calculated from multispectral images (with colour bands at 405,470,530,590,660 and 850nm) were matched to the spectrophotometer output through multiple linear regression. All spectra were transformed to emphasize the wavelength regions most impacted during bleaching, following which two critical reflectance values were scaled to a single bleaching score. The bleaching assessment method was tested in a time-course experiment comprising seeds from five green-pea genotypes stored for six months. Each sample was divided into two so that half of the seeds were stored in the dark and the remainder were exposed to controlled light to exaggerate bleaching. Throughout this period, the samples were imaged at six-weekly intervals. Assessment of bleaching by the IA method agreed well with spectrophotometer measurements, achieving a Lin's concordance statistic of 0.99 and 0.96 for the calibration and time-course samples respectively. The IA method proved more versatile because assessments could be made on individual seeds enabling the computation of bleaching uniformity within each sample. This method captured differences between genotypes in the extent, rate and uniformity of bleaching. All genotypes exhibited susceptibility to bleaching when stored under the controlled light conditions. Excell was observed to be the most susceptible genotype with the greatest bleaching-rate and OZB1308 displayed the most colour-stability.

BACKGROUND AND OBJECTIVES: The nutritional benefits of Lentil (Lens culinaris Medik.) have been widely acknowledged. Enriching wheat flour using pulses such as lentil flour is a way of increasing both the nutritional and functional content of wheat‐based foods. The properties of lentil that may have specific health benefits to the individual are also widely acknowledged. Functional compounds from plant‐based foods are commonly attributed to polyphenols, inhibitors, vitamins, and soluble and insoluble fiber. Water‐soluble carbohydrates, (WSCs) consisting predominantly of oligosaccharides, make up part of total dietary fiber. The beneficial role of oligosaccharides promoting probiotic health is widely acknowledged. Equally, it is recognized that oligosaccharides cause irritable bowel syndrome limiting the ability for some individuals in consuming pulses. FINDINGS: We investigated changes in water‐soluble carbohydrate (WSC) composition during the dough fermentation phase of bread making and quantified the residual WSC in the bread. As expected, the addition of lentil flour increased the WSC profile of the resulting composite flours which included raffinose, stachyose, ciceritol, and verbascose. A threefold decrease was observed only for verbascose during the dough mixing phase; however, during fermentation, raffinose and stachyose decreased, but ciceritol was not affected. CONCLUSIONS: The baking process may reduce the effects of IBS suffered by some individuals who consume lentil products prepared by traditional methods. Our study concluded that bread prepared from wheat–lentil flour results in a more complex carbohydrate profile and may potentially enhance the prebiotic functionality compared with bread made from wheat alone. SIGNIFICANCE AND NOVELTY: It is now recognized that alternate sources of protein can be gained using plant‐based constituents. The functional properties of plant‐based compounds are also widely accepted. Processing, such as fermentation and baki

BACKGROUND AND OBJECTIVES: Lentil (Lens Culinaris. Medik) is a highly nutritious food staple widely consumed within India subcontinent and the Mediterranean region. Although gaining popularity in western diets, wheat will continue to be a major crop as it can be used to manufacture a wide range of products. The nutritional benefits of lentils are acknowledged, particularly as a source of high protein so the incorporation of lentil flour into wheat‐based foods has the potential to improve the nutritive value of range food products. Twelve blended flours were made using different concentrations of red lentil cotyledon, wheat, and additional gluten. A blending study was undertaken to access yeast vitality, rheological properties of dough and baking characteristic of resulting bread. FINDINGS: High ratio blends of lentil flour had no negative effect on yeast vitality even at the highest concentration of 40%. Increasing substitution of lentil flour was highly correlated to increased protein (r = 0.98) and ash (r = 0.95) and a concomitant decrease in dough strength but not extensibility. Loaf volume and baking quality were also compromised at higher concentrations. At a concentration of 5% lentil flour, there were no deleterious effects on dough quality traits or on baking quality. The addition of bakers’ gluten 0.1 g/gram flour had a restorative effect on the rheological and baking characteristics of wheat–lentil composites at higher concentrations of up to 20%. CONCLUSIONS: Our results show that optimal baking quality of wheat–lentil flour can be achieved using either low concentrations of up to 5% lentil flour or up to 20% lentil flour with the addition of gluten which maintained a superior loaf and crumb quality. SIGNIFICANCE AND NOVELTY: The protein and ash content of baked breads significantly increased when wheat was partially substituted with lentil flour. The concentration of lentil flour decreased dough strength and dough development time and decreased loaf volu

The determination of water‐soluble carbohydrate (WSC) concentrations in forages is important for quantifying forage feed quality as WSC is not only a major source of energy but is also associated with the grazing preferences of forages and subsequent intake by livestock. This study describes a high‐throughput ultra‐performance liquid chromatography (UPLC) method to analyse WSC concentrations of various forage samples. The application of the new method is demonstrated by investigating the WSC concentrations in (i) temperate forages at different tiller heights, and (ii) summer forage crops grown under rain‐fed and irrigated conditions. The UPLC method provided a more descriptive, specific and precise analysis of WSC concentration compared to the colorimetric method. Grass tiller height had a significant effect on total WSC concentration and individual sugar. With increasing tiller height, sucrose concentration increased and fructan and total WSC concentrations decreased. While irrigation treatment increased the dry‐matter yield of all nine summer forage crops analysed, there was no consistent effect of irrigation on WSC concentration.

Field peas (Pisum sativum L.) are generally traded based on seed appearance, which subjectively defines broad market-grades. In this study, we developed an objective Linear Discriminant Analysis (LDA) model to classify market grades of field peas based on seed colour, shape and size traits extracted from digital images. Seeds were imaged in a high-throughput system consisting of a camera and laser positioned over a conveyor belt. Six colour intensity digital images were captured (under 405, 470, 530, 590, 660 and 850nm light) for each seed, and surface height was measured at each pixel by laser. Colour, shape and size traits were compiled across all seed in each sample to determine the median trait values. Defective and non-defective seed samples were used to calibrate and validate the model. Colour components were sufficient to correctly classify all non-defective seed samples into correct market grades. Defective samples required a combination of colour, shape and size traits to achieve 87% and 77% accuracy in market grade classification of calibration and validation sample-sets respectively. Following these results, we used the same colour, shape and size traits to develop an LDA model which correctly classified over 97% of all validation samples as defective or non-defective.

The puroindoline proteins (PINA and PINB) of wheat display lipid-binding properties which affect the grain texture, a critical parameter for wheat quality. Interestingly, the same proteins also display antibacterial and antifungal properties, attributed mainly to their Tryptophan-rich domain (TRD). Synthetic peptides based on this domain also display selectivity towards bacterial and fungal cells and do not cause haemolysis of mammalian cells. However, the mechanisms of these activities are unclear, thus limiting our understanding of the in vivo roles of PINs and development of novel applications. This study investigated the mechanisms of antimicrobial activities of synthetic peptides based on the TRD of the PINA and PINB proteins. Calcein dye leakage tests and transmission electron microscopy showed that the peptides PuroA, Pina-M and Pina-W→F selectively permeabilised the large unilamellar vesicles (LUVs) made with negatively charged phospholipids mimicking bacterial membranes, but were ineffective against LUVs made with zwitterionic phospholipids mimicking eukaryotic membranes. Propidium iodide fluorescence tests of yeast (Saccharomyces cerevisiae) cells showed the peptides were able to cause loss of membrane integrity, PuroA and Pina-M being more efficient. Scanning electron micrographs of PINA-based peptide treated yeast cells showed the formation of pits or pores in cell membranes and release of cellular contents. Gel retardation assays indicated the peptides were able to bind to DNA in vitro, and the induction of filamental growth of E. coli cells indicated in vivo inhibition of DNA synthesis. Together, the results strongly suggest that the PIN-based peptides exert their antimicrobial effects by pore formation in the cell membrane, likely by a carpet-like mechanism, followed by intracellular mechanisms of activity.

Using a barley mapping population, 'Vlamingh' × 'Buloke' (V × B), whole grain analyses were undertaken for physical seed traits and malting quality. Grain density and size were predicted by digital image analysis (DIA), while malt extract and protein content were predicted using near infrared (NIR) analysis. Validation of DIA and NIR algorithms confirmed that data for QTL analysis was highly correlated (R (2) > 0.82), with high RPD values (the ratio of the standard error of prediction to the standard deviation, 2.31-9.06). Endosperm hardness was measured on this mapping population using the single kernel characterisation system. Grain density and endosperm hardness were significantly inter-correlated in all three environments (r > 0.22, P < 0.001); however, other grain components were found to interact with the traits. QTL for these traits were also found on different genomic regions, for example, grain density QTLs were found on chromosomes 2H and 6H, whereas endosperm hardness QTLs were found on 1H, 5H, and 7H. In this study, the majority of the genomic regions associated with grain texture were also coincident with QTLs for grain size, yield, flowering date and/or plant development genes. This study highlights the complexity of genomic regions associated with the variation of endosperm hardness and grain density, and their relationships with grain size traits, agronomic-related traits, and plant development loci.