Electron beam irradiation as a method for preservation of the chemical composition of medicinal and aromatic plants
Conference Paper
Overview
Overview
abstract
Medicinal and aromatic herbs are widely consumed as infüsions, being used since the eariy
ancient times as medicinal plants for different diseases, displaying antioxidant,
antimicrobial and anti-inflammatory properties [l]. Electron beam irradiation is used for
several purposes, being highlighted not only as decontamination but also as a preservation
technique [2]. In this work the effects ofdifferent doses ofelectron beam (EB) irradiation
(O kGy - contrai, l kGy and 10 kGy) on chemical and nutritional compounds oï ASoysia
citrodora P., Melissa officinalis L., Melitüs melissophyllum L. and Mentha piperita L. was
evaluated. The nutritional value was detennined by official methodologies for food
analyses, determining the content of proteins, lipids, carbohydrates and ash. Individual
profiles of sugars were determined by HPLC-RI, fatty acids by GC-FID, organic acids by
UFLC-PDA and tocopherols by HPLC-fluorescence. The proximate composition remained
nearly unaffected, independently of plant species or irradiation dose. Regarding sugars
profile, the main changes were a decrease in the disaccharides content, while an opposite
behaviour was observed form the monomer units (probably originated after the lysis ofthe
disaccharides). The most noticeable variations in organic acids were exhibited by the plant
species with the highest contents in these molecules, particularly the decrease observed in
M. officinalis and M. melissophyllum. Among tocopherols, a and P isoforms were the most
susceptible to irradiation; using a l kGy dose tended to increase tocopherols' leveis m A.
citrodora, while the 10 kGy dose had the same effect on M. melissophyllum. M. piperita
presented higher tocopherols' leveis, independently of the dose. Finally, EB irradiated
samples presented higher percentages ofmonounsaturated fatty acids than the control ones.
