Katsuobushi emits a pleasant aroma upon shaving, however, the aromatic intensity gradually fades. We examined the aroma compounds in katsuobushi before and after shaving for a period of time to determine their contribution to the aroma of freshly shaved katsuobushi. The percentage of aldehydes decreased from 2.8% to 0.7%, after shaving. Alcohol and aldehyde content increased after 24 h storage at 32% relative humidity, and hexanal content was 11 times higher than at 0 h. Conversely, many compounds decreased, including dimethyl sulfide and pyridine which decreased by factors of 0.02 and 0.06, respectively. The moisture content decreased by approximately 10%, while changes in moisture content and aroma compounds were suppressed at 83% relative humidity. The aroma of freshly shaved katsuobushi decreased significantly after storage at 32% relative humidity for 24 h, with a lowered score already seen at 6 h (p<0.05). While the majority of aroma compounds decreased within 2 h of shaving, we inferred that fading of the aroma of freshly shaved katsuobushi is attributable to a change in aroma composition, caused by an increase of certain aroma compounds.

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 We investigated the annual variations in physicochemical properties and eating qualities of the ‘Yumepirika’ variety of Hokkaido rice grown under different climatic conditions, cold summer years, hot summer years, and average summer years. We found that climatic variations have an impact on the quality properties of brown, milled, and cooked rice. The setback value of gelatinization characteristics was the highest in cold summer years, suggesting that the cooked rice quality becomes more susceptible to starch retrogradation under such conditions. Among the sensory evaluation items, the greatest variation with climatic conditions was observed in the stickiness of cooked rice, with significant differences (p<0.01) between the cold and hot summer years. Understanding the range of variation in eating quality due to climatic conditions is deemed crucial for the stable production of high-quality ‘Yumepirika’ rice.

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 The foods used in pork dishes in the early Showa period were compared with those of today, and the expression of the deliciousness of pork dishes was investigated. The main foods used in pork dishes are vegetables and seasonings, as well as those of today also. The similarity of foods was higher in seasonings than in vegetables, and the diversity of seasonings was lower in the early Showa period than them of today. The diversity of vegetables between the early Showa period and the present age was similar to them. Seasonings are similar to those in the early Showa period and modern times in that soy sauce, salt and sugar are often combined with pork dishes. In the early Showa period, miso was often used, and there were many seasonings that used only one seasoning or a combination of soy sauce. Pork is considered to be a food with a good aroma, texture and is also used as soup stock. Pork was considered to contribute to the taste of pork dishes.

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