Chemical composition and stability of the hydrosols obtained during essential oil production. II. The case of Picea glauca (Moench) Voss., Solidago puberula Nutt., and Mentha piperita L.

Abstract

The aim of this work is to know if the hydrosols produced on a commercial basis are stable over at least 12 months at room temperature. The chemical composition of the oils and hydrosols collected from wild plantations were determined by GC-FID and GC/MS analyses. The components obtained from the hydrosols are mainly monoterpene alcohols, aldehydes and ketones and as such the composition of the hydrosols is different or very different from that of the corresponding oils: the oil with the most important fraction of the hydrocarbon compounds, the composition of the two phases is different. Benzyl alcohol, a compound not observed in the oil of S. puberula is by far the main compound (ca. 73%) observed in the corresponding hydrosol. Camphor is the main product observed in both oils (ca. 20%) and hydrosol (ca. 67%) of P. glauca. Menthol and menthone and their isomers (ca. 75%) are both observed in the oil and the hydrosol of M. piperita. These main compounds seem relatively stable in acidic water over the observation period.