Near-infrared spectroscopy (NIRS) application for quantitative characterization of edible grains.

Abstract

The near-infrared spectroscopy (NIRS) an analytical method in the field of laboratory instrumentation. The attempts have been made to explore the utility of NIR for variety of samples matrices. The present work has been undertaken to assess the efficacy of NIRS method for quantitative characterization of wheat grains in terms of hardness. Since wheat is the staple food and its hardness is one of the basic quality traits being used in local and international trade. In addition to the NIR-spectroscopy, wheat grain samples were also analyzed through standard methods for hardness such as hardness index (HI) and particle size index (PSI). Samples had hardness scores ranging between 55.5 and 79.1. A positive correlation shown among the values of NIRS and HI (r = 0.92). However, PSI values were weakly related to HI (r = -0.46) and NIR (r = -0.30) values. The grouping of data further suggested that the samples belonged to the medium and hard wheat classes. The correlation coefficients (r) evaluated for medium wheat class and hard wheat class were 0.92 and 0.70, respectively. Thus, the NIR spectroscopy technique showed better performance for grains possessing medium hardness. Since the NIR technique is rapid, reliable and does not require expertise for operation, it has a great potential for utilizing in grain testing laboratories to support our grain industry and trade.