Physical Properties and Sensory Evaluation of the Chinese Vegetable Choy Sums Grown in Greenhouses in Japan

Abstract

 To determine quality characteristics, the physical characteristics of the flower stalks of 28 varieties and lines of choy sum and related species grown in greenhouses under low-to-moderate temperature conditions in Japan were investigated. Early varieties and lines sown on November 6 exhibited less flower stalk toughness, whereas those sown on February 6 showed greater flower stalk toughness caused by the low temperatures immediately after sowing, which suppressed flower stalk enlargement. Sensory traits of the early choy sum variety with moderate physical properties were also compared with those of other vegetables (Japanese mustard spinach and asparagus). The flower stalks of choy sum showed less bitterness and leafy smell than those of other vegetables, and the leaves were thin and flabby in texture compared to those of the other vegetables. Choy sum flower stalks and leaves eaten together were rated as slightly less sweet but more tender than those of the other vegetables.