Abstract
To elucidate the effect of fertilization management on the grain yield and the quality of roasted barley tea in ‘Kashimamugi’ and ‘Kashima Goal’, we conducted a field experiment on an upland field converted from a paddy field. There was a significant negative correlation between the grain protein content and L* value of the roasted grain in the 2023 season, indicating that the higher protein content improved the color of roasted barley grain. In the 2023 season, a significant negative correlation was also observed between the L* value of roasted barley flour and the grain hardness. In this study, fertilization management did not affect the yield; however, the grain protein content and the quality of roasted barley tea were significantly improved by nitrogen top dressing at the full heading time. In addition, nitrogen top dressing at the full heading time increased the 1000-grain weight. A higher top to basal nitrogen dressing ratio raised the grain protein content but hardly affected the roasted barley tea quality. On the other hand, in the 2023 season, a higher top to basal nitrogen dressing ratio increased the degree of late emerging heads, suggesting that this fertilization management was not suitable for barley cultivation of barley for roasted barley tea. These results suggested that the increase in grain protein by application of nitrogen top dressing at the full heading time contributed to the production of high-quality barley for barley tea.
