The value-added improvement of prefectural farm products is important for the development of Ibaraki agriculture as a growth industry, and investigation of the impact of storage during long-term shipment and the development of high-quality products are needed. Japanese chestnuts, which are a specialty product of Ibaraki Prefecture, were wrapped without sealing in polyethylene film during storage (packaging that was folded the mouth of the bag). Results showed that the packaging treatment could decrease desiccation of the chestnuts (floating chestnuts), and combined with storage at -1 °C, could delay browning of the fleshy interior compared to conventional storage (2 °C) for around one month. It was further clarified that fungal growth could be suppressed. In addition, by using a retort sterilizer for the purpose of cooking and sterilization concurrently, stewed sweet chestnuts characterized by a bright color and softness were produced, and the original flavor and nutritional components of the Japanese chestnuts were retained.

We examined whether the findings of previous studies modeling strawberry jam could be applied to commercially available strawberry jam. The texture attributes (hardness, thickness, smoothness, melting and coating) of 10 commercial jam samples were investigated by sensory evaluation. This was conducted by 16 panelists who were trained in evaluating sensory attributes. The short back extrusion (SBE) method was used for instrumental analysis. In the SBE method, the apparent viscosity was calculated using the measurement conditions and shear rate corresponding to each of the texture attributes obtained in previous studies. Furthermore, the correlation coefficient between each sensory evaluation value and the apparent viscosity was determined. The findings showed that a knowledge of any of the sensory attributes of model strawberry jam can be applied to commercially available strawberry jam. These results suggest that the texture of strawberry jam can be controlled by using the apparent viscosity as an index.

In order to consider the effect of salt dissolubility on miso quality, we produced miso using salt of different particle sizes. By comparing the chemical constituents of miso produced with salt of different particle sizes over 20 days from the start of preparation, we found that the amount of amino acids increased and sugar decreased in miso that was produced using salt with a large particle size. At approximately 50 days of aging, the effect of salt particle size on miso quality decreased. However, a difference in the color of the miso due to a difference in the salt particle size was observed after aging for 50 days. The findings suggest that miso with a strong red color can be produced using salt with a large particle size. In addition, the diffusion behavior of the salt in the raw materials of the miso during the aging process was examined using a conductivity meter. As the NaCl concentration in the miso increases, conductivity also increases. Although the conductivity meter used in this experiment is usually used to measure conductivity in a liquid, the possibility of determining NaCl concentrations in the miso, which is a paste, was suggested. The findings showed that estimating the dissolution and diffusion behavior of salt during the miso aging process was possible using a conductivity meter.

In June 2021, Hazard Analysis and Critical Control Point (HACCP) became mandatory for food manufacturers. This study surveyed on quality assurance (QA) procedures in 10 major food manufacturers. As a result, an original management system and a QA system were established in each company. In food manufacturing, not only HACCP, but also Global Food Safety Initiative certification programs have been introduced. Furthermore, raw material management, QA after food product shipment in the food supply chain, and quality-related risk management have been implemented and are functioning. Based on these survey results, changes to QA were suggested after making HACCP mandatory. It is expected that this research will further improve the QA level of domestic food manufacturers.

At the Small Research-Discussion on Cereal Grains in the annual meeting of the Japanese Society for Food Science and Technology in 2021, Dr. Hitoshi Iwahashi (professor of the Faculty of Applied Biological Sciences, Gifu University) gave a lecture entitled "Use of high pressure treatment in bread making process ". The content of the lecture included prevention of bacterial growth in bread dough before fermentation and baking by means of hydrostatic pressure treatment (about 100 MPa) and/or carbon dioxide gas pressure treatment (about 1 MPa) and generation of sugars and amino acids through the endogenous enzyme reaction. By these techniques, it will be possible to improve the taste as well as Yudane bread-making method.

We applied high hydrostatic and carbon dioxide pressure conditions to the production of Yudane-like bread. The advantages of the Yudane method are the unique texture and sweetness attributed to endogenous enzymes. We employed a hydrostatic pressure of 50 MPa at 30°C, and a high carbon dioxide pressure of 1 MPa at 40°C. These high pressure conditions inhibited microbial growth but enabled enzymatic reactions. Increases were observed in reducing sugars, glutamic acid and water soluble proteins, and decreases were observed in gliadin and glutenin. The use of high-pressure conditions in breadmaking can contribute to a diversity of breadmaking processes. The biological effects of high pressure conditions and the reason why microbes are inactivated by these conditions are also discussed.