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Citrulline is a non-protein building amino acid that plays important roles in nitric oxide production, vasodilation and ammonia detoxification. It is structurally related to arginine and is most abundant in melons and other cucurbit species. Most current methods for the quantification of citrulline and arginine require time-consuming chemical derivatization steps, and often use more expensive detection methods such as fluorescence detection. Hence, this study aimed to develop a simple and rapid reversed-phase high-performance liquid chromatography method using ultraviolet detection (RP-HPLC–UV), without requiring any analyte derivatization. The method was used to quantify the citrulline and arginine content of 13 Australian fruit and vegetable cultivars, comprising 11 species from 7 genera and 5 families. The highest citrulline contents were found in mature citron melon (Citrullus lanatus var. citroides) fruit (39.2 mg/g dry weight basis), which also had the highest citrulline: arginine ratio of 17.8. Red watermelon (Citrullus lanatus) flesh also contained high levels of citrulline (22.9 mg/g), with lower concentrations in other melons, pumpkin and squash (1–3 mg/g). Arginine levels were highest in red watermelon flesh (8.1 mg/g). This extraction protocol and HPLC method may be suitable for screening large number of samples for citrulline and arginine contents.

Helicoverpa armigera Hubner (Lepidoptera: Noctuidae) is one of the most damaging insect pests globally, causing estimated global economic losses of over 3 billion US dollars annually. Crops most affected include cotton, tomato, soybean, grain crops such as corn and sorghum, chickpea and other pulses. Adults of this species possess strong migratory abilities (>2000 km), high fecundity and rapid reproductive rates; completing 4–6 generations per year in most cropping regions. Furthermore, the larvae are polyphagous, with a wide and diverse host range and possess the ability to enter diapause in order to survive adverse climatic conditions. At present, it is distributed across most of Oceania, Asia, Africa and southern Europe and has recently spread to South America. Various control measures have been trialled or proposed for the treatment of this pest, including synthetic insecticides, phytopesticides, microbial pesticides, macro‐biocontrol agents (both parasitoids and predators) and the development of genetically modified crops (e.g. Bt cotton). Successful control necessitates the use of an integrated pest management (IPM) approach, wherein biological, chemical and physical control measures are combined for the greatest control efficacy.

While plums are widely touted for their health benefits, there is little data available on the levels of beneficial anthocyanins and other antioxidative compounds found in commercial Australian plums. As such, this study aims to provide context data on the typical levels and variation in plums available to consumers. Six commercial plum varieties were sourced from Central Queensland grocery stores, including two varieties developed and grown exclusively in Australia ��� Croc Egg and ���King Midas��� yellow plums ��� as well as four varieties grown both in Australia and internationally: black, Dapple Dandy, red and sugar plums. These were analyzed for antioxidants, phenolics, anthocyanins and mineral contents. Significant differences between varieties were observed in the levels of total phenolics (65���160 mg gallic acid equivalents 100 g���1 on a fresh weight basis), antioxidants (cupric reducing antioxidant potential of 174���542 mg Trolox equivalents 100 g���1) and anthocyanins (0.3���21.5 mg cyanidin-3-glucoside equivalents 100 g���1), as well as in the flavonols quercetin (0.02���0.15 mg 100 g���1) and quercetin-3-glucoside (0.21���2.87 mg 100 g���1). Mid-infrared attenuated total reflectance (MIR-ATR) spectroscopy combined with principal component analysis could separate varieties based on their phytochemical composition. The findings suggest that commercially available Australian plums contain similar levels of health-benefitting compounds to those found internationally, although the levels of these compounds depend strongly on the considered variety.

Total monomeric anthocyanins from six commercial plum varieties were extracted using two protocols, viz methanol/water extraction through end-over-end shaking and ethanol/water extraction in a shaking water bath; adapted from the Australian Wine Research Institute (AWRI) standard method. Anthocyanins were determined using the Association of Official Analytical Chemists (AOAC) standard protocol and a modification of the AWRI method. The mean relative standard deviation was found to be similar between methods, at 13.5% and 9.9%, respectively. On average, the anthocyanin concentrations given by the AWRI method were 27% higher than those obtained using the AOAC standard method. This was attributed to the AWRI method not correcting for haze or matrix interference, but estimating the anthocyanin concentration from the absorbance at a single wavelength. Anthocyanin measurements on the two extractions using the same measurement protocol supported this, indicating that the methanolic extracts gave a higher anthocyanin yield than the ethanolic extracts. Furthermore, HPLC profiling of the anthocyanin content demonstrated significantly more anthocyanins were extracted through the methanol extraction protocol. The methanol/water extraction protocol and AOAC standard method are much simpler to perform than the AWRI method and appear to be at least as precise. Thus this extraction and spectrophotometric protocol is well suited to future work on plum matrices. The extraction method is also more suitable for the subsequent photometric and/or HPLC determination of phenolic and total antioxidant contents.

Although Australia is the largest exporter of faba bean globally, there is limited information available on the levels of bioactive compounds found in current commercial faba bean varieties grown in this country. This study profiled the phenolic acid and flavonoid composition of 10 Australian faba bean varieties, grown at two different locations. Phenolic profiling by HPLC-DAD revealed the most abundant flavonoid to be catechin, followed by rutin. For the phenolic acids, syringic acid was found in high concentrations (72.4–122.5 mg/kg), while protocatechuic, vanillic, p-hydroxybenzoic, chlorogenic, p-coumaric, and trans-ferulic acid were all found in low concentrations. The content of most individual phenolics varied significantly with the variety, while some effect of the growing location was also observed. This information could be used by food processors and plant breeders to maximise the potential health benefits of Australian-grown faba bean.

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 baking, can alter the concentration and functionality of plant-based compounds. In this study, we identified the changes in carbohydrate composition that occur in a wheat–lentil composite flour under the conditions of fermentation and baking.

Annual ryegrass is one of the most serious, costly weeds of winter cropping systems in Australia. To determine whether its competition-mediated plant defence mechanisms effect on wheat grain quality, wheat (cv. Yitpi) and annual ryegrass were grown under two levels of CO2 (400 ppm; (a[CO2]) vs 700 ppm; (e[CO2]), two levels of water (well-watered vs drought) and two types of competition (wheat only; (W), and wheat × annual ryegrass; (W × R) with four replicates. The competition × [CO2] interaction had a significant effect on wheat grain protein content, where it was increased in W × R under both e[CO2] (+17%) and a[CO2] (+21%). Grain yield, total grain reducing power and phenolic content were significantly affected by [CO2] × drought × competition. In a summary, annual ryegrass competition significantly altered the wheat grain quality under both [CO2] levels (depending on the soil water level), while also decreasing the grain yield.

A growing demand for plant‐based protein has seen a resurgence in the utilisation of pulses such as lentil and chickpea as a protein‐rich substrate to produce food products traditionally based on animal or cereal protein. Additionally, pulses offer metabolic benefits due to the bioactivity of compounds including phenolic acids, simple and complex carbohydrates and a more complete amino‐acid profile which is not found in cereal grains. However, there is an increasing concern in the formation of acrylamide in food which occurs when asparagine, an abundant amino acid found in pulses, forms a complex with the reducing sugars; glucose, fructose, and maltose. Recent studies in animal models have shown that acrylamide is carcinogenic and therefore is a concern for humans. High levels of acrylamide have been reported particularly in fried products, primarily due to the Maillard reaction which amplifies the formation of acrylamide. This study investigated the levels of acrylamide in bread, cookies, and extruded products prepared with wheat‐lentil composite flour. Our research found that extrusion resulted in a significantly lower concentration of acrylamide compared to traditional baking. Additionally, increasing the amount of lentil within the composite significantly increased the net concentration of acrylamide for all bread, cookies and extrudate products.

With growing consumer interest and demand for health‐benefiting functional foods such as faba beans, particularly evident in developed countries, commercial production of this crop is increasing. In concert with increased production levels comes an equally great need for the inexpensive rapid measurement of nutritional parameters for quality determining purposes. As an analytical tool, near‐infrared spectroscopy has been well explored for the quantification of proximate nutritional composition, such as protein, starch and oil contents in faba bean and faba bean‐derived products. Near‐infrared spectroscopy has also been demonstrated to have potential for the noninvasive prediction of low‐level micronutrients such as the total polyphenol content in faba bean and faba bean‐derived products, although further exploration in this area is required to provide a more acceptable model. In some instances, the authors may be inadvertently measuring micronutrient concentrations through a secondary correlation with certain macronutrients. It is particularly difficult to determine if this is the case if exacerbated by the lack of an independent validation test set in the paper in question. The associated technique of mid‐infrared spectroscopy shows particular promise for the rapid, noninvasive characterisation of structural components of faba bean, such as carbohydrates and proteins. Complementary applications of these two technologies are likely to yield a wealth of potential applications.

There is growing interest in pulses such as faba bean for the development of foods with enhanced nutrition, functionality, and health benefits. In this study, seed material from 10 faba bean varieties, grown in replicated field trials in South Australia over consecutive seasons (2016 and 2017), were analysed for ferric reducing antioxidant potential, total phenolics, and total monomeric anthocyanins. Differences in the macrochemical composition of varieties was investigated using attenuated total reflectance mid‐infrared spectroscopy. The mean ferric reducing antioxidant potential of the varieties ranged from 237 to 531 mg trolox equivalents 100 g−1; the total phenolics from 258 to 571 mg gallic acid equivalents 100 g−1; and the total monomeric anthocyanins from 12.7 to 21.0 mg cyanidin‐3‐glucoside equivalents 100 g−1. Statistically significant variances in all three measures were found between varieties. Attenuated total reflectance Fourier transformed mid‐infrared spectroscopy was found to provide a rapid assessment of the phytochemical composition of the samples. Partial least squares discriminant analysis was able to classify samples by growing year with reasonable accuracy (>87%). There is significant variation in the antioxidant, phenolic, and anthocyanin contents between Australian faba bean varieties. Mid‐infrared spectroscopy may prove to be a valuable screening tool for breeders and researchers in the future.

Background and Aims The concentration of free trans-resveratrol in wine is expected to increase with storage because of hydrolysis of piceid (a bound form of resveratrol). This study measured resveratrol concentration in 16 Australasian red wines ranging from 1 to 6 years old, both initially and after a storage period of 16 months under ambient conditions. Methods and Results During the study period, trans-resveratrol concentration decreased by an average of 76%. The decay in trans-resveratrol was first order over the tested range of wine source and vintage, with a mean trans-resveratrol bottle-storage half-life of 8 (±1 SD) months. Decay rate was remarkably independent of growing condition and year. Conclusion The data suggest isomerisation of trans- to cis-resveratrol via residual enzymatic activity (rather than being catalysed by light or acid). Significance of the Study In general, this may reduce the anticipated health benefits of the wine given that cis-resveratrol displays fewer health benefits than the trans isomer.

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 the concentration of fructose, sucrose, or the raffinose family oligosaccharides (RFOs). As expected, phenolic acids, procyanidin, kaempferol glycoside, and kaempferol trihexoside were detected in lentil–wheat composites but not in wheat. All phenolic acids significantly increased with increasing concentrations of lentil flour in composite; however, their concentration decreased as a result of the extrusion process. Differences in concentrations of procyanidin and kaempferol glycoside were detected between Grade 1 and frost-affected lentil in both the composite flour and the extrudate. Conclusions The extrusion process has the effect of altering the composition of the raw material. This was evident by a decrease in protein percentage phenolic compounds and to a lesser effect the water-soluble carbohydrates. No changes in RFOs was observed. The complete loss of glucose and a significant reduction in maltose provide a healthier carbohydrate profile as the carbohydrates are low fermentable sugars. The reduction in phenolic acids a result of extrusion may help to reduce the antinutritional activity particularly in grains where the concentration of phenolic acids is high. This study found that functionality of downgraded lentil is similar to the premium grade, and more expensive raw material. This knowledge may assist in reducing the increasing issue of food waste where often downgraded products are not used in the production of food. Significants and novelty In order to meet world food security needs, it is predicted that global food production will need to increase by at least 70% by 2050. Therefore, the utilization of all possible protein sources including downgraded pulses, such as lentil, will become increasingly more important. Furthermore, due to climate change increasingly more variable weather conditions will result in the production of below optimum grains. Understanding how to best utilize both premium and downgraded grains is a desirable outcome to minimize food waste.

The finger lime (Citrus australasica) is endemic to Australia, attracting recent culinary interest due to its unique organoleptic profile. However, there is limited information available on the comparative chemical composition of current commercially available Australian cultivars. This study investigated the phytochemical composition of five Australian finger lime cultivars: Durhams Emerald, Chartreuse, Rhyne Red, Red Champagne and a hybrid cultivar (P1f2-10). The pulp ascorbic acid content ranged from 23 to 54 mg/100g (fresh weight basis), while the total phenolic content ranged from 144 to 197 mg/100g. In the pulp, flavonoids were more abundant than hydroxybenzoic and hydroxycinnamic acids, while phenolic acids were found at higher concentrations in the peel. The highest pulp antioxidant capacity and anthocyanin content were found in the Rhyne Red cultivar. The predominant volatile compounds present in peel were limonene, γ-terpinene, β-citronellol and citronellal, with distinct volatile chemotypes for each cultivar. Finger limes show promise for commercial development as a functional food.

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 volume while increasing crumb firmness in resulting bread. The addition of gluten improved the rheological and product quality of bread which allowed higher concentrations of lentil flour to be used in bread making. Balancing the ratio of lentil flour and gluten to optimize the rheological properties will result in a composite wheat–lentil bread with acceptable baking performance and enhanced nutritional benefits for consumers.

β-Damascenone, a potent aroma component of in a variety of grapes and wines, has a sensory threshold of approximately 2ng/L in water. This C13 norisoprenoid ketone is principally generated from hydrolyzable precursors, which was glycosidically bound. Isolation of β-damascenone-yielding precursors from Cabernet Sauvignon grape skins using C18 reversed phase chromatography followed by droplet countercurrent chromatography yielded multiple chromatographically distinguishable precursor fractions. The existence of multiple precursors was further evident from the varying ratios of 3-hydroxy- β-damascone (the by-product): β-damascenone generated upon acid hydrolysis of the chromatographically distinguishable precursor fractions.