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Chickpea (Cicer arietinum L.) is a significant pulse crop in Australia, with an industry value of over AUD 1.3 billion. However, there are few studies investigating the levels of health-benefiting constituents in desi chickpeas and the impacts of variety, growing location, and season on these constituents. This study aimed to study the levels of health-benefiting constituents in desi chickpeas, including 97 samples of Australian desi chickpeas, comprising 18 varieties, grown in a range of field trials across four Victorian locations and three growing seasons. Various physical characteristics and phytochemical compositions were determined in the samples, including 100-seed weight, colour, moisture content, total phenolic content (TPC), ferric-reducing antioxidant potential (FRAP), cupric-reducing antioxidant potential (CUPRAC), and total monomeric anthocyanin content (TMAC). The screening results showed a significant difference in TPC, TMAC, and FRAP among different desi varieties, suggesting there may be variation in their potential health benefits. Furthermore, the growing location and growing season significantly impacted all analytes. Correlation analysis revealed a number of significant correlations, including a moderate positive correlation between the b* colour and the antioxidant capacity and total phenolic content. This work provides the first detailed insight into the range of phenolic and antioxidant contents found in Australian desi chickpeas and the impact that genotype, location, and season can have.

Consumers are showing increasing awareness of the concept of ‘functional foods’: foods that can provide health benefits in addition to their nutritional value. There is particular demand for foods with a high antioxidant and phenolic content, which may improve cardiovascular health, reduce inflammation, and slow or prevent the onset of chronic, non-communicable diseases. However, there is a lack of comprehensive databases using consistent analytical protocols to analyze the antioxidant and phenolic content of different food types, particularly in regional areas such as Australia. Over the past four years, our laboratory has analyzed over 1000 food-related samples using several antioxidant capacity assays (ferric reducing antioxidant power—FRAP—and cupric reducing antioxidant capacity—CUPRAC), as well as the total phenolic content (TPC) using the Folin–Ciocalteu method. Here, we provide a summary of these data by different food types to inform researchers, policy planners, nutritionists, and consumers about the typical levels of antioxidants and total phenolics found across a range of Australian foodstuffs, particularly grains. The highest antioxidant and phenolic contents were typically found in native Australian fruits, while grains, nuts, and non-native fruits showed lower antioxidant and phenolic contents. Spices, processed foodstuffs, and non-fruit native Australian foods showed an intermediate content. Furthermore, medicinally used plants showed a much higher phenolic content and antioxidant capacity compared to non-medicinal plants. Finally, we present correlations between the various analytes.

Three peanut genotypes were cultivated under ambient and elevated CO2 conditions. Elevated CO2 treatment was associated with higher total phenolic content (TPC) values in the shoots and roots of all genotypes. Seeds showed lower levels of TPC compared to the other plant tissue, showing a decline in all three genotypes, and no differences between the CO2 treatments were observed. The Crude Protein (CP) content in seeds varied significantly among the genotypes, and elevated CO2 treatment was associated with mild increases (not significant) in CP of 4 and 6% in Holt and Alloway cultivars, respectively. It is worth mentioning that Kairi contained the highest CP content under elevated CO2 (29%).

Nigella sativa, an annual herbaceous flowering plant of the Ranunculaceae family, is considered an important medicinal plant due to the presence of several bioactive compounds in its seeds, including both volatile and non-volatile compounds. The cultivation of numerous genotypes of N. sativa is seen in different parts of the world with varying compositions of such chemical compounds. Since the variation in composition determines the quality grade of the seeds, this study was carried out to explore the compositional variation of twelve different genotypes of N. sativa cultivated in Central Queensland, Australia. The results showed total phenolic content (TPC), FRAP and CUPRAC (antioxidants), and thymoquinone in the range of 291–529 mg GAE/100 g DW, 703–966 mg TE/100 g DW, 2533–3416 mg TE/100 g DW, and 219–349 mg/100 g DW, respectively. The highest values of TPC, thymoquinone, FRAP, and CUPRAC were observed in genotypes AVTKS#E, AVTKS#F, AVTKS#4, and AVTKS#D, respectively. The lowest values of TPC and FRAP were observed in genotype AVTKS#24, and the CUPRAC and thymoquinone were lowest in genotype AVTKS#23 and AVTKS#1, respectively. Monomeric anthocyanins were absent in the methanolic seed extracts of all nigella genotypes. There was a strong positive correlation among the TPC, CUPRAC, and FRAP. However, despite thymoquinone being reported as a strong antioxidant in the literature, there was no significant correlation of thymoquinone with TPC or CUPRAC, and only a weak positive correlation with FRAP. Overall, the genotypes with comparatively higher values of thymoquinone, TPC, and antioxidant capacity (both FRAP and CUPRAC) showed particular potential for breeding programs.

The production of high-quality rum requires a carefully controlled fermentation process, which is determined by the physicochemical and nutritional properties of the molasses used as a substrate. The flavor, aroma, and alcohol content of the final product are heavily influenced by the composition of molasses. This paper presents the results of an extensive analysis of molasses, a byproduct of sugar production that has various applications in food and feed industries. The physicochemical properties and nutritional composition of molasses were investigated using a range of analytical techniques including Brix, moisture content, pH, total ash content, total dissolved solids, crude protein, sugar content, total nitrogen, free amino acids, amino acids, mineral content, vitamins, and organic acids. This study analyzed molasses samples obtained from three painted concrete constructed storage wells at the Bundaberg Distilling Company. The results indicated that the molasses samples possessed a substantial sugar concentration, with sucrose being the most abundant, ranging from 35.02 to 35.27% w/w. These findings support the traditional use of molasses in rum fermentation and use as an alternative feedstock for the synthesis of various value-added chemicals. The pH of the molasses was slightly acidic, and the total ash content was relatively high, ranging from 8.76 to 13.55% w/w, indicating the presence of mineral salts. Mineral content varied among the samples, but all three contained significant levels of sodium, phosphorus, potassium, calcium, and magnesium. All the samples contained essential amino acids and vitamins, but their levels varied. The molasses also contained varying levels of different organic acids, including acetic, propanoic, aconitic, formic, valeric, lactic, citric, and malic acids. The analysis revealed significant differences in ash content, nitrogen compounds, and minerals between storage wells, indicating inherent variability between batches. However, key fermentable sugars did not significantly differ between samples, and blending or standardization is recommended to minimize batch-to-batch variation prior to fermentation. This study provides valuable information on the composition and quality of molasses, which can be used to optimize its utilization in rum fermentation and various other applications.

This study compared the performance of near-infrared spectroscopy (NIRS) and mid-infrared spectroscopy (MIRS) for the prediction of moisture, protein, total phenolic content (TPC), ferric reducing antioxidant potential (FRAP) and total monomeric anthocyanin (TMA) content in 65 samples of Australian wheat flour. Models were constructed on 50 of the wheat samples, with the 15 remaining samples used as a dependent test set. NIRS showed excellent results for the prediction of protein content (R2test = 0.991; RMSEP = 0.22% w/v) and acceptable to good results for TPC (R2test = 0.83; RMSEP = 3.9 mg GAE/100 g), FRAP (R2test = 0.92; RMSEP = 5.4 mg TE/100 g) and moisture content (R2test = 0.76, RMSEP = 0.62% w/v). Similarly, MIRS showed the best results for protein prediction (R2test = 0.93, RMSEP = 0.62% w/v) and acceptable results for moisture content (R2test = 0.83, RMSEP = 0.65% w/v), FRAP (R2test = 0.83, RMSEP = 7.0 mg TE/100 g) and TPC (R2test = 0.73, RMSEP = 5.6 mg GAE/100 g). However, the TMA content could not be predicted. Finally, moving window analysis was conducted to determine the optimum wavelength ranges for predicting selected analytes. On average, this improved RMSECV values by an average of 18–20% compared to the corresponding full wavelength models, when using the same component selection method. The results confirm that infrared spectroscopy may be useful for the real-time quantitation and/or screening of key quality parameters in wheat, such as protein, TPC and antioxidant capacity.

The aim of the present study was to evaluate the potential of handheld near-infrared (NIR) and benchtop mid-infrared (MIR) spectroscopy for the rapid prediction of antioxidant capacity, dry matter, and total phenolic contents in cayenne pepper (Capsicum annuum ‘Cayenne’). Using NIR spectroscopy, the best-performing model for dry matter had an R2pred = 0.74, RMSEP = 0.38%, and RPD of 2.02, exceeding the best results previously reported in the literature. This was also the first study to predict dry matter content from the mid-infrared spectra, although with lower accuracy (R2pred = 0.54; RMSEP = 0.51%, RPD 1.51). The models for antioxidant capacity and total phenolic content did not perform well using NIR or MIR spectroscopy (RPD values < 1.5), indicating that further optimization is required in this area. Application of support vector regression (SVR) generally gave poorer results compared to partial least squares regression (PLSR). NIR spectroscopy may be useful for in-field measurement of dry matter in the chili crop as a proxy measure for fruit maturity. However, the lower accuracy of MIR spectroscopy is likely to limit its use in this crop.

Fermented juice from the noni tree (Morinda citrifolia) is a traditional medicinal product used by South Pacific Islanders to treat a wide range of ailments, including cancer, inflammation and obesity, as well as improving overall wellbeing. Many of its bioactive properties have been suggested to arise from the high antioxidant capacity and phenolic content found in the juice. However, there have been limited investigations into the phenolic profiles of noni juice produced locally in the Pacific. This study aimed to investigate the chemical composition and bioactive properties of noni juice. The first phase of this study used liquid chromatography with tandem mass spectrometry (LC-MS/MS) to characterise the phenolic composition of five brands of commercial noni juice produced in the South Pacific region. A total of 21 phenolic compounds were putatively identified, with the most abundant generally being rutin, 4-hydroxybenzoic acid and gentisic acid. Vastly differing phenolic profiles were found between the noni juice brands. Significant differences were also found in their antioxidant capacities and total phenolic contents. Of the three major phenolic compounds identified, gentisic acid showed the highest antioxidant activity (640% higher than Trolox). Additionally, the noni juice showed no significant anti-acetylcholinesterase activity and no to moderate cytotoxicity against two cancer cell lines (HeLa and HT29). These results indicate that the phytochemical profiles—and hence, the expected bioactive properties—are likely to vary significantly between different noni juice brands. Furthermore, the anti-cancer activity of non-concentrated noni juice appears to be relatively low.

The utilisation of high gravity wort possessing a higher sugar content is frequently used to increase the capacity and efficiency of beer production. In such an environment, osmotic stress, lower nutrient availability, ethanol toxicity and elevated CO2 concentrations may decrease the sustainability of yeast performance and have a negative impact on the desired end product. Traditionally, apparent attenuation has been used as a standard measure of fermentability. Here, we describe a miniature fermentation assay with a defined fermentation media that could be used to assess fermentability on a small scale, including determination of the original gravity and final gravity of the medium for trials using four yeast strains. The results obtained using the defined media were approximately comparable to those obtained using regular wort in terms of their real attenuation limits and specific gravity, although the defined media demonstrated lower final pH values compared to the wort for several strains. With further optimisation, the mini fermentation process applied to a defined medium could provide the foundation for future analytical research into the brewing process, using techniques such as high-performance liquid chromatography (HPLC) and quantitative polymerase chain reaction (qPCR).

Australia is a minor producer of chilli, with the industry producing around 2500 tonnes of chillies per year. Due to the small size of the industry, there is currently limited research on the typical levels of capsaicinoids in the Australian crop and the relationship between these constituents and other agronomic and nutritional factors. This study applied a rapid, maceration-based extraction protocol with end-over-end shaking, coupled with a HPLC-DAD method for the analysis of capsaicin and dihydrocapsaicin in 20 Habanero chilli samples from Queensland, Australia. All samples were from the same growing season (2020) but were taken from different within-field locations to ensure that all of the variability within the growing site was sampled. In addition to the capsaicinoid measurements, the total phenolic content was measured using the Folin-Ciocalteu assay, while antioxidant activity was measured using the Ferric Reducing Antioxidant Power (FRAP) method. The capsaicin concentration of the samples ranged from 1474–3916 mg/kg, while the dihydrocapsaicin content ranged between 638–1757 mg/kg, giving total pungencies of approximately 32,000 to 83,000 Scoville Heat Units. Similarly, the total phenolic content varied from 1000–1608 mg gallic acid equivalents/100 g, while the antioxidant activity ranged from 301 to 455 mg Trolox equivalents/100 g. Pearson linear correlation analysis revealed that the capsaicin and dihydrocapsaicin contents were strongly positively correlated with one another (R2 = 0.73; p < 0.001), with a mean capsaicin: dihydrocapsaicin ratio of 2.4:1. Furthermore, there was a moderate positive correlation between the total capsaicinoid content and total phenolic content of the samples (R2 = 0.58; p < 0.01), as well as a strong correlation between the total capsaicinoid content and FRAP (R2 = 0.81; p < 0.001). However, dry matter content was not significantly correlated with capsaicinoid content, total phenolic content or antioxidant activity (p > 0.05 for all). These results may be used to inform future breeding programs for high-capsaicin chilli varieties and support further research into the agronomic and genetic factors driving capsaicin and dihydrocapsaicin content.