title: Effect of microwave drying and oven drying on the water activity, color, phenolic compounds content and antioxidant activity of coconut husk (Cocos nuciferaL.).
abstract: The coconut (Cocos nuciferaL.) husk is basically composed by fiber and pith material and remained under-utilized. This is an important source of phenolic compounds that could be used as functional ingredients. The aim of this study was to determine the effect of: oven-drying (OD) and microwave drying (MD), on the water activity, color, phenolic compound content and antioxidant activity of coconut husk. The OD was performed at 60 °C for 12 h and MD was performed at 900 W for 10 min. The total phenolic content (TPC) in fresh coconut husk was 64.2 mg GAE/g dry wt and significant higher than observed after OD and MD of 35.8 and 45.5 mg GAE/g dry wt, respectively. Ten phenols were identified in fresh and dehydrated coconut husks. The husk MD showed an increase in the content of gallic, 4-hydroxybenzoic, ferulic and syringic acids and epicatechin compared with the fresh; while coconut husk OD and MD, showed a decrease in the content of vanillic acid, vanillin, catequin and kaempferol. The antioxidant activity decreased after both OD and MD. However, MD resulted in a better antioxidant activity in husk than OD. MD of husk resulted into better retention of preserved color, TPC and TFC than OD.
authors: Escuela Nacional de Ciencias Biológicas, Departamento de Ingeniería Bioquímica, Instituto Politécnico Nacional, Wilfrido Massieu esq. Cda. Luis Stampa s/n, c.p. 07738 Gustavo A. Madero, Ciudad de México, México.
authors: Lourdes
authors: L
authors: Valadez-Carmona
authors: Escuela Nacional de Ciencias Biológicas, Departamento de Ingeniería Bioquímica, Instituto Politécnico Nacional, Wilfrido Massieu esq. Cda. Luis Stampa s/n, c.p. 07738 Gustavo A. Madero, Ciudad de México, México.
authors: Rosa María
authors: RM
authors: Cortez-García
authors: Escuela Nacional de Ciencias Biológicas, Departamento de Ingeniería Bioquímica, Instituto Politécnico Nacional, Wilfrido Massieu esq. Cda. Luis Stampa s/n, c.p. 07738 Gustavo A. Madero, Ciudad de México, México.
authors: Carla Patricia
authors: CP
authors: Plazola-Jacinto
authors: Coordinación de Cooperación Académica, Instituto Politécnico Nacional, Avenida Miguel Othón de Mendizábal s/n, Colonia La Escalera, c.p. 07738 Gustavo A. Madero, Ciudad de México México.
authors: Hugo
authors: H
authors: Necoechea-Mondragón
authors: Escuela Nacional de Ciencias Biológicas, Departamento de Ingeniería Bioquímica, Instituto Politécnico Nacional, Wilfrido Massieu esq. Cda. Luis Stampa s/n, c.p. 07738 Gustavo A. Madero, Ciudad de México, México.
authors: Alicia
authors: A
authors: Ortiz-Moreno
keywords: Antioxidant activity; By-product; Coconut husk; HPLC; Microwave/oven drying; Phenolics