Antioxidant Capacity in Vanilla Extracts Obtained by Applying Focused Microwaves

Adalith Rojas-López,María P Cañizares-Macías

doi:10.4236/fns.2013.48a030

Abstract

ORAC method and a continuous flow injection method based on Folin-Ciocalteau reaction (FI-FC) were used for determining the antioxidant activity in extracts obtained by using focused microwaves. Analysis of the antioxidant capacity (AC) of the main compounds of vanilla (vanillin, p-hydroxybenzaldehyde, p-hydroxybenzoic acid and vanillic acid) was also carried out. Vanilla extracts obtained by using focused microwaves had a higher AC (between 72% and 117%) than the obtained by conventional methods. Vanillin had a linear correlation with the antioxidant capacity of the extracts and it is the most influential compound in the antioxidant power. The AC calculated by the ORAC method and the FI-FC method had a ratio 2:1 because of different kinetics and reaction mechanisms of the antioxidants with the reagents, so it is necessary more than one method to establish the antioxidant power in food. On base on the results of the present study microwaves energy can be used to obtain vanilla extracts to improve the AC of them.

Highlights

The early news from vanilla are in the middle 15th century, when Aztecs conquered the Totonaca Empire who used vanilla to make a drink named “xocolatl”
Trolox is the most used reagent by ORAC method due to its high sensibility, caffeic acid has been used because it has a high antioxidant power [36]
The antioxidant capacity (AC) by the ORAC method increased between 82% and 117% in the extracts obtained by focused microwaves in comparison with the obtained by the maceration method; by the FIFC method the increased was between 72% and 97%

Summary

Introduction

The early news from vanilla are in the middle 15th century, when Aztecs conquered the Totonaca Empire who used vanilla to make a drink named “xocolatl” (chocolate). Libellus de Medicinalibus Indorum Herbis, Cruz Balbiano codex, were the first document where vanilla is named with its Nahuatl name: “tlilxochitl” (black flower) [1]. For three centuries Mexico was the only producer of vanilla in the world. From vanilla began to spread through Africa and Asia [2]. Vanilla is the only orchid that produces an important commercial fruit for its flavour and smell. There are more than 110 species of vanilla, but the Vanilla planifolia, known as Vanilla fragans, is the most important source of the natural commercial vanilla [1,3,4]

Methods

Results

Conclusion