Glucosinolate content of Brassica vegetables‐Chinese cabbages Pe‐tsai (Brassica pekinensis) and Pak‐choi (Brassica chinensis)

The glucosinolate content of 19 cultivars of pe‐tsai and three cultivars of pak‐choi Chinese cabbage (Brassica pekinensis Lour) Rupr and (Brassica chinensis L, respectively) has been determined using high performance liquid chromatography. The levels of total glucosinolates were 0.097‐0.337 g kg−1 fresh weight (mean 0.198) in pe‐tsai and 0.39‐0.704 g kg−1 (mean 0.534) in pak‐choi. The main components present were (2‐hydroxybut‐3‐enyl‐progoitrin), but‐3‐enyl‐ (gluconapin), 5‐methylsulphinylpentyl‐ (glucoalyssin) and pent‐4‐enyl (glucobrassicanapin) glucosinolates, respectively. In comparison with other UK brassicas and American cultivars of Chinese cabbage, both the UK‐grown pak‐choi and pe‐tsai are low in glucosinolates.