Classification and Authentication of Barley (Hordeum vulgare) Malt Varieties: Combining Attenuated Total Reflectance Mid-infrared Spectroscopy with Chemometrics

Attenuated total reflectance (ATR) mid-infrared (MIR) spectroscopy combined with chemometrics was explored as a tool to classify and authenticate Australian barley varieties. Grain samples (n = 162) were sourced from eight commercial barley varieties and analysed in the MIR range. Principal component analysis (PCA), discriminant partial least squares regression (PLS-DA), linear discriminant analysis (LDA) and soft independent modelling of class analogy (SIMCA) were used to classify the barley grain samples according to variety. PLS-DA correctly classified barley varieties between 91 and 100 %. The results have demonstrated the usefulness of ATR-MIR spectroscopy combined with chemometrics as a rapid method to classify barley grain samples according to their variety. Although MIR is not routinely available at the receival point in most of the cereal trade companies, it has the potential to be used in breeding programmes.