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Beverage quality in the brewing industry is heavily influenced by ingredient properties. The contribution of raw ingredients such as yeast and hops to beer flavor is well understood. However, the influence of barley genotype and/or environment on flavor (the malt 'source') is largely unexplored. Here, a study was performed to determine (i) if there are metabolite differences among six commercial malt sources, (ii) if differences in malt chemistry are reflected in the chemistry of the beer, and (iii) if the differences in the beer chemistry impact sensory attributes of beer, through flavor and flavor stability. Six distinct sources of malts (six varieties from three maltsters) were brewed into six beers using a recipe designed to evaluate differences in flavor. Metabolomics and ionomics was used to characterize chemical variation among the six malts and beers using UHPLC- and HILIC-MS (non-volatile metabolites), HS-SPME/GC–MS (beer volatiles), and ICP-MS (malt metals). These analyses detected a total of 5042 compounds in malt, of which 217 were annotated and included amines, amino acids, fatty acids/lipids/fatty acyls, saccharides/glucosides/sugar acids/sugar alcohols, carboxylic acid derivatives, organic acids, phenolics/benzenoids, purines, pyrimidines/pyridines, terpenes, and organosulfurs. A total of 4568 compounds were detected in beer, of which 246 were annotated and included esters, aldehydes, and alcohols. Statistical analysis revealed chemical variation among the six malts (50/217 malt metabolites varied) and beers (150/246). The six beers were evaluated for flavor using a modified descriptive analysis for 45 sensory traits at 0, 4, and 8 weeks of storage at 4 °C. Principal component analysis of the sensory data revealed flavor differences among the six beers at 8 weeks, and the malt-type Full Pint was described as fruity and Meredith as corn chip. The metabolite and sensory data were integrated and revealed associations between flavor profiles in beer and the annotated malt and beer. The fruity or corn chip flavor profiles in beer were associated beer purines/pyrimidines, volatile ketones, amines, and phenolics, and malt lipids, saccharides, phenols, amines, and alkaloids. Taken together, these data support a role of malt source in beer flavor and flavor stability. As a raw ingredient, malting barley genotypes can be evaluated for a contribution to flavor, and this may be a future target for plant breeding, agronomy, and malting efforts to selectively improve flavor, flavor stability, and quality in beer.

Fruit developing in different canopy positions are exposed to distinct light environments that can influence their maturation process and internal quality development. Maturation, a highly regulated process at the molecular level, significantly impacts fruit quality. Our understanding of the true effect of various pre-harvest factors on fruit quality is limited due to poor control of maturity among comparisons in previous studies. Here, an experiment was conducted to assess the true impact of canopy vigor and position (bottom: 0.3–1.2 m and top: 2.1–3.0 m) on ‘Sierra Rich’ (low vigor, LV) and ‘Cresthaven’ (high vigor, HV) peach fruit internal quality. Given the lower vigor of ‘Sierra Rich,’ it was recorded that light was more evenly distributed throughout the canopy thus, hypothesized that this could be leading to fruit of uniform quality across the different positions. Fruit from the different canopy positions were assessed at the commercial harvest stage for size, dry matter content (DMC) and physiological maturity (index of absorbance difference, IAD), using non-destructive visible (Vis) to near-infrared spectroscopy (NIRS). Fruit maturity and DMC advanced/increased with the elevated height of canopy in both cultivars. However, when controlling for equal maturity, only fruit coming from the vigorous ‘Cresthaven’ trees showed a significant (P ≤ 0.05) ΔDMC of 2.1 % between extreme canopy positions. Non-targeted metabolite profiling was carried out using gas chromatography mass spectrometry (GC–MS) on the mesocarp and exocarp of equally mature peach fruit samples. Mesocarp metabolite profiling of equally mature fruit coming from the different canopy positions demonstrated minimal metabolic variation. However, significant metabolite variation across canopy positions was observed in the exocarp of the HV cultivar. In general, sucrose, sorbitol and catechin were more abundant in higher quality, exposed to high-light environment fruit, while increased aspartic acid, asparagine, threonine, citric acid, monosaccharides (sorbose and fructose), butanoic acid and shikimic acid were associated with inferior quality, exposed to low-light environment fruit. Overall, this combined physiological and metabolomic analysis provides insight into the true impact of canopy position and underscores the light environment-related metabolic regulations that facilitate peach fruit quality development.

Produced water (PW), a wastewater resulting from hydraulic fracturing and oil and gas production, has been utilized in arid regions for irrigation purposes and potentially presents a new water source for crop irrigation in areas of increasing water scarcity. However, there is a potential for both synthetic and geogenic contaminants in these waters to accumulate in irrigated food crops. This study assessed how water treatment technologies targeted at removal of salinity (i.e., total dissolved solids) and organic chemical content (i.e., dissolved organic carbon) from PW to achieve agricultural irrigation standards altered the impact of inorganic contaminants and nutrient uptake on two salt-tolerant food crops, sunflower (Helianthus annuus) and wheat (Triticum aestivum). The impacts of the treatment technologies on inorganic contaminant loadings in the irrigated soils were also assessed. Treatment technologies to improve PW quality decreased the adverse impacts on plant health; however, plant health was more affected by dilutions of PW than by the treatment technologies employed. Phenotypically, plants irrigated with 90% dilution (low) treatment groups, regardless of treatment technology, were comparable to controls; however, plants watered with high proportions (50%) of raw or treated PW displayed stunted growth, with reduced height and leaf area, and sunflower seed saw 100% yield loss. Although phenotypically similar, plants of the low treatment groups exhibited changes in the ionome, illustrating the influence of PW on plant uptake, translocation, and accumulation of metals, salts, and micronutrients. In addition, bioavailability of metals and nutrients was impacted by the unique and complex PW matrix: bioconcentration factors traditionally used to evaluate risk may therefore over or underestimate accumulation.

Soil microbes live in close association with plants and are crucial for plant health and fitness. Recent literature revealed that specific microbes were cultured at distinct developmental stages of Arabidopsis. It is not clear how fast the roots, depending on their developmental stage, can alter the root-associated microbiome. In this study, Arabidopsis, grown under sterile conditions at precisely distinct developmental stages were supplied with a soil microbial slurry. Within four days, roots selected specific microorganisms depending on plant development, and Proteobacteria among other bacterial groups were found to colonize the roots irrespective of developmental stage. Moreover, exposure to a microbiome resulted in modulation of phytohormone levels at different stages of Arabidopsis.

The roots of plants have the ability to influence its surrounding microbiology, the so-called rhizosphere microbiome, through the creation of specific chemical niches in the soil mediated by the release of phytochemicals. Here we report how these phytochemicals could modulate the microbial composition of a soil in the absence of the plant. For this purpose, root exudates of Arabidopsis were collected and fractionated to obtain natural blends of phytochemicals at various relative concentrations that were characterized by GC-MS and applied repeatedly to a soil. Soil bacterial changes were monitored by amplifying and pyrosequencing the 16 S ribosomal small subunit region. Our analyses reveal that one phytochemical can culture different operational taxonomic units (OTUs), mixtures of phytochemicals synergistically culture groups of OTUs, and the same phytochemical can act as a stimulator or deterrent to different groups of OTUs. Furthermore, phenolic-related compounds showed positive correlation with a higher number of unique OTUs compared with other groups of compounds (i.e. sugars, sugar alcohols, and amino acids). For instance, salicylic acid showed positive correlations with species of Corynebacterineae, Pseudonocardineae and Streptomycineae, and GABA correlated with species of Sphingomonas, Methylobacterium, Frankineae, Variovorax, Micromonosporineae, and Skermanella. These results imply that phenolic compounds act as specific substrates or signaling molecules for a large group of microbial species in the soil.

The complexes (cnt)2[Fe(nta)Cl2], where nta = nitrilotriacetate and cnt = Et4N+ or PyH+, catalyze the air oxidation of thiols to disulfides under ambient conditions. Dithiols are converted to linear and cyclic oligomers that differ in their terminal groups as a function of the counterion, cnt. Cysteine ethyl ester was converted to the corresponding cystine diethylester in high yield.