Drying Effects on Major Volatile and Phenolic Components of Achillea filipendulina Lam

Abstract

Several drying methods including freeze drying (FD), air drying (AD), and blanched or unblanched vacuum microwave drying (BVMD and UVMD) were applied to fresh flowers or leaves of Achillea filipendulina “Gold Plate”. The major headspace volatile components of fresh and dried samples were determined by capillary gas chromatography/mass spectrometry (GC-MS). Spectrophotometric changes of total phenolics (TP) and tartaric esters (TE) in the samples were measured in their ethanolic extraction (80 % v/v). Hunterlab method was used for color determination of dried samples. VMD was the fastest among methods. Drying treatments affected the volatiles in both leaves and flowers and by using analysis of variances followed by Tukey’s pairwise comparison test, significant (p < 0.5) changes for the contents of TP and TE in dried samples was observed. However, either total volatile components or TP and TE were more concentrated in leaves compared to flowers in all treatments as well as fresh tissues. Hunterlab values revealed that FDflowers and leaves had the least darkened samples and followed by unblanched VMD treatment. Among the treatments, freeze drying method showed the best for aroma volatiles and phenolics retention, particularly, for dried leaves.