Abstract: The difference in the volatile composition of Kushui rose hydrosol under different salt treatment conditions was studied in an attempt to reveal the influence of salt treatment on the quality of rose hydrosol. In this experiment, Kushui rose hydrosol was prepared from the flowers of Rosa setate × R. rugosa using a device developed by ourselves, and its volatile components were analyzed by solid phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS). The study results showed that a total of 86 volatile compounds were identified from the hydrosols of fresh and NaCl treated flowers, 57 volatile compounds of which were present in the fresh hydrosol mainly citronellol and linalool, and 61 volatile compounds in the salted hydrosol mainly citronellol, linalool and terpineol. Compared with the fresh one, the contents of linalool and terpineol in the salted hydrosol were significantly increased (P < 0.05), while the content of citronellol was significantly decreased (P < 0.05). The contents of phenolic compounds in the two hydrosols were similar (P > 0.05), which were 3.84% and 3.81%, respectively; there were also 10 aldoketones (0.42%) and 3 terpenes (0.21%) in the fresh hydrosol. Additionally, there were 11 aldoketones (0.69%) and 1 terpene (0.17%) in the salted hydrosol. Although the two types of hydrosols were mainly composed of alcohols, the types, quantities and relative percentages of alcohols were quite different between them. At the same time, the aroma of the fresh hydrosols was more abundant and sweeter than the salted one, and the color was clearer. This study provides theoretical support for the preparation and quality identification of rose hydrosols.

Key words: Kushui rose hydrosols; salt treatment conditions; quality; solid phase microextraction-gas chromatography-mass spectrometry; volatile compounds