Assessment of malting characteristics of different Indian barley cultivars

Optimization of the germination time of proso and foxtail millets to enhance the bioactive properties, antioxidant activity, and enzymatic power and reduce antinutritional factor

The germination of millets is a traditional yet underutilized method to enhance their nutritional and functional attributes. This study investigates the impact of germination time on the bioactive, enzymatic, and antinutritional properties of proso millet (Chino Dude) and foxtail millet (Kaguno Red and Kaguno White) varieties. Germination was conducted over five days (0-5 days), and changes in total phenolic and flavonoid content, tannin content, antioxidant activity, diastatic power, α-amylase activity, reducing sugars, and trypsin inhibition activity were measured. A two-way ANOVA revealed significant effects (p < 0.05) of varietal differences and germination time on these properties. Total phenolic and flavonoid content and antioxidant activity increased significantly (p < 0.05) unit day 3 of germination after which it decreased until day 5. Tannin content and trypsin inhibitor decreased significantly (p < 0.05) from day 1 to day 5 of germination, whereas diastatic power and α-amylase increased (p < 0.05) with an increase in germination time. The optimal germination time was determined to be 3.46 days using multiple regression models to maximize bioactive compounds and enzymatic activity while minimizing antinutritional factors. Moreover, Kaguno Red exhibited the highest bioactive levels, while Kaguno White had the lowest trypsin inhibition activity, indicating varietal-specific differences in analyzed parameters. This study highlights the potential of tailored germination strategies to enhance the nutritional and functional profiles of millets, providing actionable insights for functional food development in regions reliant on millet as a staple crop.

Barley Grain Proteome Assessment Using Multi-Environment Trial Data and Machine Learning

Proteomics can be used to assess individual protein abundances, which could reflect genotypic and environmental effects and potentially predict grain/malt quality. In this study, 79 barley grain samples (genotype-location-year combinations) from Californian multi-environment trials (2017-2022) were assessed using liquid chromatography-mass spectrometry. In total, 3104 proteins were identified across all of the samples. Location, genotype, and year explained 26.7, 17.1, and 14.3% of the variance in the relative abundance of individual proteins, respectively. Sixteen proteins with storage, DNA/RNA binding, or enzymatic functions were significantly higher/lower in abundance (compared to the overall mean) in the Yolo 3 and Imperial Valley locations, Butta 12 and LCS Odyssey genotypes, and the 2017-18 and 2021-22 years. Individual protein abundances were reasonably predictive (RMSECV = 1.25-2.04%) for total, alcohol-soluble, and malt protein content and malt fine extract. This study illustrates the role of the environment in the barley proteome and the utility of proteomics and machine learning to predict grain/malt quality.

Relationships among Structure, Physicochemical Properties and In Vitro Digestibility of Starches from Ethiopian Food Barley Varieties

Studying diversity in local barley varieties can help advance novel uses for the grain. Therefore, starch was isolated from nine Ethiopian food barley varieties to determine starch structural, pasting, thermal, and digestibility characteristics, as well as their inter-relationships. The amylose content in the varieties significantly varied from 24.5 to 30.3%, with a coefficient of variation of 6.1%. The chain length distributions also varied significantly, and fa, fb1, fb2, and fb3 ranged from 26.3 to 29.0, 48.0 to 49.7, 15.0 to 15.9, and 7.5 to 9.5%, respectively. Significant variations were also exhibited in absorbance peak ratios, as well as thermal, pasting, and in vitro digestibility properties, with the latter two parameters showing the greatest diversity. Higher contents of amylose and long amylopectin fractions contributed to higher gelatinization temperatures and viscosities and lower digestibility. Structural characteristics showed strong relationships with viscosity, thermal, and in vitro digestibility properties. Cross 41/98 and Dimtu varieties are more suitable in functional food formulations and for bakery products. These results might inspire further studies to suggest target-based starch modifications and new product development.

Malting quality of seven genotypes of barley grown in Nepal

There has been very limited work on the malting quality of barley grown in Nepal. This work used completely randomized experiment for seven barley genotypes, namely Xveola-45, Coll#112-114/Muktinath, Xveola-38, Solu uwa, NB-1003/37-1038, NB-1003/37-1034, and Bonus, collected from Hill Crop Research Program (Dolakha, Nepal) to study the effect of genotypes on the chemical composition and functional properties of barley and malt. Barley was steeped for 24 hr followed by 72 hr germination in room temperature (25 ± 3°C). Germinated barley was dried (45°C/6 hr, 50°C/4 hr, 55°C/8 hr, 70°C/1 hr, 80°C/3 hr) in a cabinet drier. Multistage dried barley was then ground to pass through a 250 µm screen. Among the chemical composition, protein and reducing sugar were affected by genotype (p < .05) in barley except for β-glucan. Functional properties, particularly bulk density, water absorption capacity, oil absorption capacity, and viscosity, were affected by genotype (p < .05) in barley, whereas except for density, all the parameters were different (p < .05) for malt. The highest diastatic power among all genotypes was recorded for solu uwa (329.25 ºDP) followed by Muktinath (271.15 ºDP). There was no significant change (p < .05) in a protein of all genotypes after malting, whereas β-glucan and viscosity significantly decreased (p < .05) for all genotypes after malting. The remaining parameters for all genotypes were not affected (p < .05) by malting. Solu uwa had higher enzymatic activity, whereas Xveola-38 and Muktinath were found to be better for complimentary food preparation.

Nutritional composition and bioactivity of germinated Thai indigenous rice extracts: A feasibility study

The feasibility of the production of germinated rice extracts using indigenous rice from Southern Thailand, including Khemtong (KHT) and Khai Mod Rin (KMR) from a single location at the Pak Phanang River Basin in Nakhon Si Thammarat, was investigated. The nutritional composition and bioactivity of the germinated rice extracts from both cultivars were evaluated. Optimum germination time for both rices was 96 h, leading to the highest GABA, thiamine, free amino acid, total sugar, and α-amylase activity (p<0.05). Germinated KHT had a higher α-amylase activity than germinated KMR at all germination times. Mashing at 60°C/pH 5.5 rendered the extract with the highest GABA content (p<0.05) and desirable contents of other nutrients. In comparison with germinated Sungyod (local colored rice) and Jasmine (commercial Thai rice) extracts, KHT and KMR showed a higher scavenging activity against DPPH•, OH•, and H2O2 (p<0.05) with a comparable ABTS•+ inhibition. For metal chelation, reducing power and ACE inhibitory activity, the germinated Sungyod extract was greater than KHT/KMR. The results demonstrated the potential use of germinated local Thai rice for the production of functional beverages.

Formation of 3-deoxyglucosone in the malting process

3-Deoxyglucosone (3-DG) is a metabolite from sugar degradation obtained by the Maillard reaction. It is an important precursor compound in Strecker reactionism that directly leads to known beer aging indicators and can influence the final sensory beer quality. However, the conditions of 3-DG formation in the malting process have not yet been described. To investigate the reaction pathways of 3-DG formation, we varied the composition of reactants (sugars, amino acids) by using different malting modification levels (germination time 5-7 d; steeping degree 42-45%; germination temperature 12-14 °C); final kilning temperature (60 °C to 100 °C). After its derivatization with ortho-phenylenediamine, we analyzed 3-DG with HPLC-UV. 3-DG concentration was between 5 and 120 µmol/100 g dry weight. The formation of 3-DG increased for high malt modification levels and high final kilning temperature. The abundant formation of 3-DG in the malting process is already comparable to the occurred brewing process concentration.