title: Quantification of total pigments in citrus essential oils by thermal wave resonant cavity photopyroelectric spectroscopy.
abstract: A general theory of thermal wave resonant cavity photopyroelectric spectroscopy (TWRC-PPE) was recently proposed by Balderas-López (2012) for the thermo-optical characterisation of substances in a condensed phase. This theory is used to quantify the total carotenoids and chlorophylls in several folded and un-folded citrus essential oils to demonstrate the viability of using this technique as an alternative analytical method for the quantification of total pigments in citrus oils. An analysis of variance (ANOVA) reveals significant differences (p < 0.05) among the means of optical absorption coefficient data for the folding degree and fruit type in citrus oils. The experimental results show that TWRC-PPE spectroscopy can be used to quantify concentrations up to five times higher of total carotenoids and chlorophylls in citrus oils than UV-Vis spectroscopy without sample preparation or dilution. The optical limits of this technique and possible interference are also described.
authors.affiliation: Química Aromática S.A., Río Grande S/N, col. Santa Catarina, Acolman, C.P. 55875 Mexico State, Mexico. Electronic address: info@quimicaaromatica.com.
authors.forename: Gerardo A
authors.initials: GA
authors.lastname: López-Muñoz
authors.affiliation: Instituto Tecnológico y de Estúdios Superiores de Monterrey-Campus Estado de México, Carretera Lago de Guadalupe Km. 3.5, col. Margarita Maza de Juarez, Atizapán de Zaragoza, C.P. 52926 Mexico State, Mexico.
authors.forename: Aurora
authors.initials: A
authors.lastname: Antonio-Pérez
authors.affiliation: Centro de Investigación en Biotecnología Aplicada-Instituto Politécnico Nacional, Ex-Hacienda San Juan Molino Carretera Estatal Tecuexcomac-Tepetitla Km 1.5, C.P. 90700 Tlaxcala, Mexico.
authors.forename: J
authors.initials: J
authors.lastname: Díaz-Reyes
mesh_terms: D002338:Carotenoids / Q000032:analysis*; D002734:Chlorophyll / Q000032:analysis*; D002957:Citrus / Q000737:chemistry*; D006358:Hot Temperature; D009822:Oils, Volatile / Q000032:analysis*; D010938:Plant Oils / Q000032:analysis*; D013057:Spectrum Analysis / Q000379:methods*
chemical_list: D009822:Oils, Volatile; D010938:Plant Oils; D002734:Chlorophyll; D002338:Carotenoids
keywords: Carotenoid content; Chlorophyll content; Citrus essential oils; Optical absorption coefficient