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In recent decades, research in barley has led to improvements in several biochemical and chemical characteristics (e.g. protein, starch, β glucans) associated with malt composition and end product quality (e.g. beer). Although lipids and fatty acids (FA) represent between 1 to 3% of the grain weight (dw), they can play an important role in barley grain and malt derived materials. However, the role of lipids and FA in both barley and malt quality is still not well understood. The aim of this article is to provide an overview on the role of lipids and FA in the chemical and industrial properties of barley grain, malt and wort. [ABSTRACT FROM AUTHOR]

Variations in the amount and rates of water uptake influence the seed hydration as well as the modification of the endosperm for industrial uses (e.g., malting). The aim of this study was to investigate and interpret absorption frequencies in the mid infrared (MIR) region associated with water uptake in whole seeds, husk and endosperm of barley seeds during the initial period of soaking in water. Partial least squares (PLS) regression models for the prediction of water uptake in the set of samples yield a coefficient of determination ( R 2 ) and a standard error in cross validation of 0.75 and 2.57 (% w/w), respectively. The biological implications of this study are that the first stages of germination can be monitored using the information derived from the MIR spectra. These results also demonstrated that whole seeds, endosperm and husk derived from the same variety or genotype have different patterns in the MIR region. [ABSTRACT FROM AUTHOR]

Highlights: [•] Attenuated total reflectance and mid infrared spectroscopy was used to understand gelatinization in whole barley samples. [•] The interpretation of the data generated was achieved by the use of MIR ratios and two dimensional spectroscopy. [•] The result of this study showed that ATR-MIR spectroscopy can be used as tool to interpret differences in barley samples. [Copyright &y& Elsevier]

Highlights: [•] Water uptake by the endosperm is an important property of barley for malting. [•] Fatty acids and total lipids have an important role on determining water uptake. [•] Unsaturated fatty acids such oleic acid have an effect on water uptake. [Copyright &y& Elsevier]

Abstract: Attenuated total reflectance (ATR) mid-infrared (MIR) spectroscopy was evaluated to measure fatty acids (FA) and total lipids in intact seed barley (Hordeum vulgare) samples. Results from this study demonstrated the capability of ATR-MIR spectroscopy coupled with partial least squares (PLS) regression to measure FA non-destructively in intact barley seeds. The coefficients of determination in cross validation (R 2) and the standard error of cross validation (SECV) were 0.76 and 0.004 g 100 g−1 for stearic, 0.75 and 0.037 g 100 g−1 for oleic, 0.45 and 0.02 g 100 g−1 for palmitic acids, and 0.89 and 0.13 g 100 g−1 for total lipids, respectively. The practical implications of this study showed that ATR-MIR spectroscopy confer valuable benefits for the grain industry and in particular in breeding programs as a non-destructive high throughput method. [Copyright &y& Elsevier]

This study reports the use of near-infrared (NIR) reflectance spectroscopy combined with two-dimensional correlation (2D-COS) spectroscopy to monitor the effect of soaking and water uptake by the barley endosperm (Hordeum vulgare, L). The synchronous 2D-COS maps derived from the NIR spectra of barley endosperm showed similarities that could be explained by the regions in the spectra associated with water as well as with the biochemical and biophysical changes as a consequence of the water uptake by the grain. The results also demonstrated the potential of 2D-COS combined with NIR spectroscopy as an analytical tool to study changes in the biophysical characteristics of whole barley during steeping or soaking. This method can be used to obtain information about the effect of water uptake in other chemical characteristics of the endosperm of cereal grains. [ABSTRACT FROM PUBLISHER]

Steeping is the first operation of malting and its purpose is to increase the water content of the grain up to 43-46%; however, such a simple step encompasses several metabolic processes that affect germination and the final malt quality. The aim of this study was to evaluate the effect of initial grain protein (GP) content and starch pasting properties, measured using the Rapid Visco Analyser (RVA) on water uptake in different barley varieties. The partial least squares (PLS2) regression algorithm was used to compare the two data matrices, the independent block of variables X (RVA data and GP) and the dependent block Y (water uptake at different steeping times). The first two PLS2 loadings explained 65 and 23% of the total variation in water uptake in the barley samples. Water uptake at 1 and 2 h was poorly explained by the PLS2 models, while after 5 h the models explained more than 40% of the variability. The results from this study showed that, although a relationship between GP and water uptake exists, it is not universal for all the varieties, indicating that the relationship between GP and water uptake is varietal dependent. Copyright © 2014 The Institute of Brewing & Distilling [ABSTRACT FROM AUTHOR]

Knowledge of the chemical and structural differences between barley (Hordeum vulgare L.) varieties and breeding lines might lead to an understanding of the reasons for these differences among genotypes in relation to their malting properties. The aim of this study was to evaluate the use of attenuated total reflectance mid infrared (ATR-MIR) spectroscopy combined with univariate and multivariate methods as a high throughput screening tool to phenotype single seeds of barley. Varieties that yield high malting quality (hot water extract (HWE) > 80%) showed relatively high non-structural carbohydrates (e.g. starch) to protein and non-structural to structural (e.g. cellulose) carbohydrates ratios compared with those samples having moderate HWE (78% < HWE < 80%). The use of ATR-MIR spectroscopy and in particular the use of ratios at specific wavenumbers can provide useful information about the biophysical and chemical characteristics of the grain. [Copyright &y& Elsevier]

Highlights: [•] The combination of mid infrared spectroscopy and chemometrics was evaluated to measure pasting properties in barley. [•] The interpretation of the data generated allowed to identify regions from the MIR related to starch pasting properties. [•] The result of this study showed that ATR-MIR spectroscopy can be used to predict some starch pasting properties. [ABSTRACT FROM AUTHOR]

Abstract: Relatively few studies have examined the influence of lipids or fatty acids on starch pasting properties in barley. The aim of this study was to evaluate the use of the Rapid Visco Analyser (RVA) as a tool to examine changes in starch functionality related with free fatty acids (FFAs) and amylose content in barley flour samples. Changes in RVA parameters such as setback (STB) and final viscosity (FV) were related to differences in both FFA (oleic and palmitic acids) and amylose contents due to the diverse barley genotypes analysed. The magnitude of the RVA profile values derived from samples having high a concentration of palmitic acid (3900mg/g) was lower compared with that having the lower concentration of the same FFA (2470mg/g), displaying low FV (5666 vs 4166cP) and low STB (1625 vs 1174cP) values. Similar trends were observed for the other FFA measured. These results showed that pasting properties of barley measured using RVA are determined by a complexity of parameters, where the combination of lipids (FFA) and amylose might determine the characteristics of the material and its final use (e.g. malting). [Copyright &y& Elsevier]

Abstract: The aim of this study was to evaluate the use of near infrared reflectance (NIR) spectroscopy to monitor water uptake and steeping time in whole barley samples as a rapid and easy to use technique. Whole barley grain samples were steeped in water, and subsamples were analyzed for water uptake (gravimetric method) and using NIR spectroscopy. The spectra and the analytical data were used to develop partial least squares (PLS) calibrations to predict water uptake and steeping time. Cross validation models for water uptake and steeping time gave a coefficient of determination in cross validation (R 2) and the standard error of prediction (SEP) of 0.90 (SEP=5.36g/100g fw) and 0.92 (SEP=3.93h), respectively. This study showed that NIR spectroscopy combined with PLS regression showed promise as a rapid, non-destructive method to monitor and measure water uptake and steeping time in whole barley during soaking. [Copyright &y& Elsevier]

Abstract Mid-infrared spectroscopy coupled with chemometrics was used to identify spectral differences in malt barley associated with region (e.g. rainfall, temperature and sunlight). The observed differences in the MIR spectra confirmed that different environmental conditions of the region they are grown, explain or modulate changes in the chemical composition of the grain. Principal component analysis (PCA) was performed to identify underlying patterns and correlations in the data set. Partial least squares (PLS) regression with cross-validation was applied to develop models to predict the regions using the weather variables, the MIR fingerprint region and a combination of both. The PLS model with the combined data predicted the growing location with the standard error of cross-validation (SECV) of 3.38%, an R2 value of 0.53, a slope of 0.52 and a bias of 0.23. The exploratory approach demonstrated the usefulness of chemometrics to identify differences and similarities based on the MIR spectra. The results provided a solid foundation for hypothesising the overall degree of biochemical similarity and or difference among the samples and a quantifiable method to screen samples for further analysis. Highlights • Barley from different Australians regions was analysed using mid infrared. • Observed differences in the absorbance at specific wavenumbers related to region. • Combination of climate and MIR data provided the better classification results. [ABSTRACT FROM AUTHOR]

Improving grain yield and adaptation is achieved by synchronising crop phenology with the environment. Phenology research is complex and encounters analytical challenges in characterising genotype x environment (GxE) interactions. This paper presents a simple approach that helps to explain the environmental drivers of phenology. Photoperiod and temperature are major environmental cues for expression of crop developmental genes, and sensitivity to photoperiod is thought to be the major cause of maturity differences among Australian spring barley varieties. However, temperature and photoperiod show similar seasonal trends and strong autocorrelation makes it difficult to distinguish their relative importance in crop development. Partial Least Squares regression (PLS) was developed to handle large data sets with many correlated explanatory variables and only one dependent variable. Across 35 environments encompassing a wide range of temperature and photoperiod regimes in southern Australia, a PLS model described more than 90 % of the phenotypic variation in time to anthesis of three adapted barley cultivars. The PLS outputs defined the critical periods when photoperiod and temperature were most influential, and revealed that temperature effects are of equal or greater importance than photoperiod in determining anthesis date, which is a new finding for genotypes adapted to Australian environments. Insight into the previously elusive differential responses to changes in daily average, maximum, and minimum temperatures will assist in developing flowering models for growers that are more accurate, and assist breeders in the genetic dissection of phenology for target environments. [ABSTRACT FROM AUTHOR]