ABSTRACT
Capsaicin is an active compound in hot peppers. It has been studied for its health benefits for humans. Optical spectroscopy is an important tool for determining the optical properties or chemical composition of matter. The aim of this research is proposing an optical method to identify and quantify capsaicin in the visible range. To achieve this goal, we combined absorption and diffuse reflectance spectroscopy techniques to compute the extinction coefficient. Moreover, the concentration of the analytes was determined using the optical properties of capsaicin. Our method is a promising tool for developing a classification of capsaicin according to its percentage in chilies. The extinction coefficients are reported for 507nm and 663nm, which are the most significative. In addition, the coefficients to build the mathematical model for capsaicin are reported for Kubelka-Munk model. Finally, a comparison between capsaicin vs chilies spectra was obtained to identify spectral response. Diffuse reflectance signals allowed the identification of capsaicin and opened the possibility of this fast and easy to do method for classification and quantification of bioactive compounds.
ABSTRACT
A detailed analysis of the quaternion generic Jacobi-Fourier moments (QGJFMs) for color image description is presented. In order to reach numerical stability, a recursive approach is used during the computation of the generic Jacobi radial polynomials. Moreover, a search criterion is performed to establish the best values for the parameters [Formula: see text] and [Formula: see text] of the radial Jacobi polynomial families. Additionally, a polar pixel approach is taken into account to increase the numerical accuracy in the calculation of the QGJFMs. To prove the mathematical theory, some color images from optical microscopy and human retina are used. Experiments and results about color image reconstruction are presented.
