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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]