INDIRECT SPECTROPHOTOMETRIC DETERMINATION OF CAPSAICINOIDS IN Capsicum PEPPERS USING THE REACTION OF COMPLEX Co(II) WITH 4-(2-PYRIDYLAZO) RESORCINOL

Capsaicinoids (CAPS) are substances responsible for pungency in Capsicum. It is important to quantify these types of compounds owing to their broad application in food, pharmaceuticals, cosmetics and chemical weapons. In this work, we developed an indirect spectrophotometric method based on the colorimetric reaction between CAPS, Co(II) 3.10x10(-5) mol L-1 and 4-(2-pyridylazo) resorcinol (PAR) 6.23x10(-5) and, in cachaca: water 92: 8v/v solutions, for quantification of total CAPS in Capsicum peppers. The product of the reaction is CoPAR(2)CAPS(2) and its absorption in aquo-ethanolic solution at 510 nm is proportional to the total CAPS concentration from 0.60 to 17.94 mg L-1. The values of limit of detection and limit of quantification were 0.0004 and 0.001 mg of CAPS/g of pepper, respectively, with 4% relative standard deviation. The developed method yielded similar results to those obtained from high performance liquid chromatography, with 95% of confidence.