The difference in color profiles of green asparagus spears between spring open field production and winter Fusekomi forcing culture production
The aim of this study was to investigate varietal differences in the color profiles of green asparagus spears and their agronomic performance. Five cultivars for open field, and 4 cultivars for Fusekomi forcing were used. Spears were cut at 24 cm and yield and basic spear characteristics were evaluated. L*, a* and b* values of several parts of both bracts and stems (base green color) were measured using a colorimeter. In the open field experiment, the marketable yield of Atticus was significantly larger than UC-157, Grande and Bacchus. There was no significant difference among Bacchus, UC-157 and Grande in marketable yield. The L* values in spear head of Bacchus were significantly higher than other cultivars, and a* values in bracts of Bacchus were significantly lower than other cultivars. In the Fusekomi forcing experiment, the marketable yield of Atticus were significantly larger than Grande and Taiho Wase. There were no significant differences in L* values among 4 cultivars in all measured points, however, a* values in the head and bracts at the base of the spear were relatively higher than other cultivars with results showing that Grande had the most reddish colored heads. A questionnaire was conducted to clarify the relation between consumers selection of fresh asparagus spears and spear fresh weight, diameter, head tightness, number of bracts in spears and color profiles (bracts and stems). The results of the survey indicated that the combination of fresh weight, head tightness, spear diameter and lightness (L* value) of the head (1 cm from the tip) influenced the respondents spear selection.
Kumano, T., Yu, H. and Araki, H. (2019). The difference in color profiles of green asparagus spears between spring open field production and winter Fusekomi forcing culture production. Acta Hortic. 1258, 125-132
asparagus, spear quality, colorimeter, consumer demand