Composition of Volatile Compounds of Horseradish Roots (Armoracia rusticana L.) Depending on the Genotype

Horseradish is a perennial plant with significant antioxidant properties, and it contains about 0.2% to 1.0% of essential oil, mainly sinigrin, sinigrin-derived allylisothiocyanate and diallylsulphide. The aim of the study was to determine composition of volatile compounds of horseradish (A. rusticana L.) roots depending on the genotype. Volatiles from fresh horseradish roots of nine genotypes were extracted using solid phase microextraction with DVB/Car/PDMS fibre and were further analysed using gas chromatography-mass spectrometry. The volatile compounds were identified by comparing their mass spectra with mass spectral libraries (Nist98) and by calculating linear retention indexes and comparing them with the literature data. The studied horseradish genotypes differed both in the quantitative and qualitative content of aroma compounds. Totally 15 volatile compounds were detected, and their highest amount was found in genotype G12B. The main aroma compound of all horseradish samples was allylisothiocyanate, which formed 64-82% of the total identified volatile compounds. The obtained results were compared with those found in the literature. All horseradish samples contained significant amounts of phenylethylisothiocyanate (4-18%) that is formed from glucosinolate - gluconasturtin. The study revealed that genotype has great influence on the content of volatiles in horseradish roots.