Previous studies have reported the optimum steeping time and temperature of roasted Jerusalem artichoke tuber tea for better color, taste, and inulin content. However, studies on functional components other than inulin present in this tea are inadequate. In this study, we investigated the effects of different steeping conditions on the total polyphenol content, antioxidant capacity, and α-glucosidase and angiotensin-converting enzyme (ACE) inhibitory activities of roasted Jerusalem artichoke tuber tea. Functional components responsible for ACE inhibitory activity were also investigated. The steeping conditions were selected based on the results of previously reported studies. Total polyphenol content, 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, and α-glucosidase and ACE inhibitory activities increased on steeping the tea for 2 minutes or more in hot water or 2 hours or more in cold water. The functional component responsible for ACE inhibitory activity may be nicotianamine in unroasted tubers and Maillard reaction products in roasted tubers.

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 In this study, bread with wheat flour partially replaced with Jerusalem artichoke tuber flour, which is rich in inulin, a water-soluble dietary fiber, was made. The effects on specific volume, texture and taste were investigated after baking. Additionally, the contents of inulin after baking and the effects of retrogradation of bread after saving were discussed. The substitution ratios for Jerusalem artichoke flour were 2%, 4%, 6%, and 8% of hard flour. No substitute was used as a control. When the substitution ratio was 6%, there was no difference with control in specific volume, crumb color/hardness, and various taste qualities measured by a Taste Sensing System. In the sensory evaluation, at a substitution ratio of up to 6%, the bread had the same with control. Furthermore, the bread of 4% substitution ratio suppressed the increase in hardness of bread seven days after baking, suggesting an improvement in storability. Moreover, the inulin remained in enough quantity in the bread after baking. If the substitution rate is 4% or more, the health function of inulin could be expected in one serving of bread. Thus, it was thought that the Jerusalem artichoke flour substitute bread was promising as a Jerusalem artichoke processed product.

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 A portable leaf nitrogen measuring device is a valuable tool used for accurate and efficient field measurements of leaf nitrogen concentration for Japanese rice varieties. However, the calibration curve, obtained for Japanese rice varieties, needs to be corrected before it can be effectively applied for Chinese rice varieties, at panicle formation stage. This report further confirmed that the instrument also provides accurate measurements for Chinese rice varieties, at the ripening stage. In addition, the measured leaf nitrogen concentrations during the ripening stage enabled the estimation of the protein content of brown rice at harvest time. There is a strong correlation between the protein content of brown rice and eating quality. Therefore, it is possible to estimate the eating quality of harvested rice based on the measured leaf nitrogen concentration during the ripening period. This makes it possible to differentiate the products by processing according to the level of eating quality at the drying facility.  Note, if the leaf nitrogen concentration is not measured at the appropriate time, the correlation with the brown rice protein content will not be obtained.

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 It is necessary to achieve the product standards required by export destinations to expand the export market of Japanese strawberries. This paper summarizes the Hong Kong market’s fruit quality and packaging requirements since it is the largest export destination for Japanese strawberries. Based on the results of sensory evaluation tests, market surveys, and interviews, the Hong Kong market is expected to have a high need for the freshness, safety, and security of strawberries. In addition, large-capacity packages are more important than the current packages in the Japanese domestic market. For events such as Valentine’s Day, small packages with a special design may also have sales potential.

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