In rice flour manufacturing research, the relationship between the type of rice used and the milling quality is poorly understood. Regarding the fine rice flours used in rice bread, although the importance of both particle size and the degree of starch damage occurring during milling is recognized, other factors remain unexplained. Therefore, the milling characteristics of various types of polished rice and the features of sieved rice flour in relation to rice bread quality were examined. Labo-mill pulverization of 42 polished rice samples of 24 different types of rice was carried out until 60% of each sample passed through a 200-mesh sieve. The results indicated that pulverization time decreases with increasing amylose content of the polished rice. Chalky and floury rice mutants pulverized quickly regardless of amylose content. A high correlation (0.81, p<0.01) was observed between starch damage and the time required for pulverization. Furthermore, pulverization of rice samples of varying grain quality indicated that more immature grains required shorter milling time. In the case of pin-milling of polished rice immersed in water, the average particle diameter and degree of starch damage of the rice flour decreased and baking quality improved with increasing immersion time. The specific volume of the rice flour bread increased as the particle size decreased with further sifting of the rice flour, and the low degree of starch damage of the rice flour made the bigger specific volume in comparison with the same particle size. These results indicate that the properties of the rice and parameters of flour milling are important in rice flour bread manufacturing. Fine particle size and a low degree of starch damage are particularly important factors. Consideration of these factors is thus also necessary in the manufacturing of other products made from rice flour.

The RVA viscosity of flours of raw and roasted rice, wheat and millet, as well as cookie and pancake powders made from these flours were measured. The correlation between the RVA values and the textural properties of cakes were clarified. (1) The RVA viscosity of cookies were maintained, and there was a high correlation with the RVA values of the constituent flours. The peak viscosity and breakdown of pancakes decreased by an average of 18% and less than 7% of raw flours, respectively. (2) In cookies and pancakes, the viscosity-retentions were found to be in a rank order of breakdown ≺ peak viscosity ≺ setback values. (3) A high correlation was obtained between the peak viscosity and the maximum breaking force of cookies, and also between the peak viscosity and [maximum force × cohesiveness ] of steamed pancakes.

Powder prepared from leaves of pruned olive trees is used to feed cultured yellowtail fish in Kagawa, Japan. We investigated polyphenol (PP) content in leaves of three olive cultivars grown in Kagawa. We also investigated PP stability under various leaf preservation conditions. All three cultivars had similar PP content. Oleuropein content did not decrease when pruned olive leaves were preserved and stored indoors for 2 weeks. Finally, PP content in olive leaf powder prepared by drying and grinding was maintained for at least 12 months when preserved in a dark place at room temperature.

Miso paste mixed with broth is popular because of its convenience. However, acid phosphatase (ACP), an enzyme present in miso paste, promotes the decomposition of this type of broth. The enzyme can be inactivated by heating the miso with the broth, but this degrades both the color and the flavors of raw miso. In this study, a continuous joule heating procedure was used to inactivate ACP in miso by raising the temperature to 65°Cover a period of 4 s, then maintaining this temperature for 4 s while keeping the sample pressurized at 0.5 MPa. This procedure inactivates ACP at a temperature 10°Clower than that required using a conventional heating approach.