Characterization of maize grains with different pigmentation investigated by photoacoustic spectroscopy

Aknowledge of grains’ optical parameters is of great relevance in themaize grain technology practice. Such parameters provide information about its absorption and reflectance, which in turn is related to its color. In the dough and tortilla industries, it is important to characterize this attribute of the corn kernel, as it is one of the attributes that directly affects the quality of the food product. Thus, it is important to have techniques that contribute to the characterization of this raw material. It is traditionally characterized by conventional methods, which usually destroy the grain and involve a laborious preparation of material plus they are expensive. The objective of this study was to determine the optical absorption coefficient β for maize grains (Zea mays L.) with different pigmentations by means of photoacoustic spectroscopy (PAS). The genotypeAhad bluish coloration and genotypeBhad yellowish coloration. In addition, the photoacoustic signal obtained by two methods was analyzed mathematically: the standard deviation and the first derivative; both results were compared (Fig. 1). In combination with mathematical analysis, PAS may be considered as a potential diagnostic tool for the characterization of the grains.