Abstract
For characterization of chemical and/or physical taste evaluation of Japanese bunching onion (welsh onion), the relationship between sensory descriptions of pungency, sweetness and texture, and the chemical and/or physical properties were investigated. Pungency score of the fresh bunching onion and the amount of pungent precursors estimated by pyruvic acid production showed a strong positive correlation (r = 0.94**). Sweetness score of the heated bunching onion and brix value did not show a positive correlation, while the concentrations of glucose, fructose, total free sugar, and sucrose equivalent sweetness showed a good agreement with the sweetness score (r = 0.98** to 0.99**). Texture scores (scores of organoleptic hardness) of boiled and grilled bunching onion showed a strong positive correlation with the penetration resistance measured by cylindrical plunger (Φ3 mm) (r = 0.90* to 0.99**). As shown above, pungency and hardness of the bunching onion can be expressed as the amount of pyruvic acid and penetration resistance, respectively. The sweetness should be estimated by the concentrations of glucose, fructose, total free sugar, and the sucrose equivalent sweetness, but not the brix value.
