To increase the market niche for scallop-based food products, we developed a high-quality scallop flake food and a new type of fermented sushi using boiled scallop (izushi). Scallop flake food comprises heated adductor muscles that are shredded into coarse fibers. Scallop flake food is a useful material for various culinary preparations, and its processing method is quite simple. Such foods are expected to become popular. In the present study, conditions for thawing frozen adductor muscle, heating adductor muscle, breaking up adductor muscle fibers, and sterilizing scallop flake food were improved. We finally established a processing method for high-quality scallop flake food. Izushi is one of the traditional fermented foods consumed in the Hokkaido and Tohoku districts. However, izushi made from scallop adductor muscle has not yet been developed. One of the reasons for this is that the weak texture and taste of scallop adductor muscle are not considered suitable for izushi preparation. We therefore investigated conditions for pickling and adjusting the weight of scallop adductor muscle during the fermentation process, and found ways to improve both the texture and taste of izushi. Our innovative processes will enable novel, marketable food products based on scallop adductor muscle.

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The leaching losses of potassium from potatoes during soaking in hot water were measured at four temperatures ranging from 70°C to 100°C. The infinite cylinder diffusion model was used to describe the leaching losses, and the measured data were fitted to a model using a non-linear least squares method. The measured results agreed well with the calculated results. The values determined for the diffusion coefficients were 1.05×10⁻⁶ to 2.05×10^-6 (m²·s⁻¹), and the apparent activation energy determined from an Arrhenius-type equation was 24.4 (kJ·mol⁻¹). The applicability of using microwave for blanching potatoes was also examined. Changes in enzyme (peroxidase) activity, texture and potassium content were measured and compared between blanching by boiling water, microwaves or a combination of microwaves and boiling water. The combination of microwave and boiling water required the least amount of time for inactivation of the enzyme. Blanching using microwave tended to damage samples. Moreover, blanching using microwaves caused significant softening while the combination of microwave and boiling water caused less change in shape and texture. The residual ratio of potassium in the sample blanched using a combination of microwave and boiling was approximately 80% ; similar to that of potatoes blanched using boiling water. These results suggest that the combination of microwave and boiling water can be used for blanching potatoes.

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We discovered an anti-speck effect in roasted rice bran extracts (RRBE) by screening various food materials for ingredients which suppress speck formation in wheat flour dough. After examining the anti-speck effect of RRBE, kojic acid (KA) and L-ascorbic acid (AA) in wheat flour dough, we found that RRBE and KA exhibited similar ability to reduce speck formation while no anti-speck effect was observed for AA. We also spectrophotometrically evaluated the reducing effect in the discoloration of wheat flour slurry that included L-tyrosine. The reducing effect seen from the differences in L-values was the strongest for KA, followed by AA, and the weakest reducing effect was observed for RRBE. Tyrosinase and peroxidase were partially purified from wheat bran and the effect of both enzymes on melanin synthesis activity was investigated. No melanin synthesis activity was observed when only peroxidase was used, but melanin synthesis increased in proportion to the concentration of peroxidase when both tyrosinase and peroxidase were used. Furthermore, the inhibition activities of both enzymes were compared between RRBE, KA and AA, and RRBE showed the weakest inhibition activity among all three. Since RRBE has a similar anti-speck effect as KA, despite its low oxidase-inhibition activity, the anti-speck effect is likely due to factors other than the strength of its inhibition activity.

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We made rice bread using a mixture of wheat gluten and rice flour from koshihikari made in Fukui Prefecture, and compared the bread-making quality of samples prepared using two different mills, a jet mill and a stamp mill. We clarified the effect of freezing and thawing conditions on several characteristics of rice bread in order to improve the quality of retrogradation. The results are as follows. Frozen-thawed rice bread exhibited a large change in color value. Frozen-thawed rice bread also exhibited higher bread hardness and lower bread cohesiveness than bread just after baking. The degree of gelatinization was the highest for frozen-thawed rice bread with a water content of 90% and prepared using the stamp mill. Water content and water activity did not change much just after baking and during freezing. Rice bread prepared using the jet mill exhibited higher specific loaf volume and bread hardness than that prepared using the stamp mill. The frozen-thawed rice bread prepared using the jet mill was favorably evaluated in comparison to rice bread just after baking. Bread prepared using the stamp mill was favorably evaluated because it maintained rice cake-like characteristics during freezing. Freezing and thawing freshly prepared rice bread is one method for improving the quality of retrogradation.

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The cooking characteristics of domestic rapeseed oils were compared with those of canola oil. Domestic rapeseed oils contained specific minerals and nutrients and exhibited distinctive flavors and colors. The AV are actual indexes of deterioration. Thus, roasted rapeseed oils were judged not to deteriorate even when used as deep-frying oils. The manufacturing processes of roasting and purification affect the cooking characteristics of roasted rapeseed oils.

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Two quantitative biofilm simulation models, a deterministic model and a stochastic model with adding the stochastic term for sloughing events, were developed in the present study. Both models considered the effect of mass transfer at the liquid-biofilm interface during biofilm development. Model parameters were estimated experimentally by creating Pseudomonas oleovorans biofilms in polystyrene tubes under different nutrient levels (5%, 2% and 1%) at 5°C. Both models were shown to be well-fitted with time-course changes in biofilm quantity. The stochastic model was especially well-fitted with the distribution of biofilm quantity under each culture condition. Moreover, the model parameters reflected properties of the biofilm, such as concentration of nutrients using extracellular polysaccharide, improvement of biofilm forming ability at low substrate concentrations and decrease of the biofilm growth rate. Thus, the models are adequate for biofilm simulations. The models presented are expected to be able to predict time-course changes in biofilm quantity and to enable analysis of experimental data. Additionally, the stochastic model has the potential to estimate not only the distribution of biofilm quantity but also sloughing events, an important concept in food safety.

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We investigated the effects of extruded polished rice, brown rice, and germinated brown rice supplemented with NaCl on the blood pressure and glucose metabolism-related hormones of spontaneously hypertensive rats (SHR/Izm). Compared to baseline levels, no significant increase in systolic blood pressure was observed after intake of germinated brown rice for 13 weeks. Although plasma glucose concentrations did not significantly differ between dietary groups, the plasma C-peptide concentration was significantly lower in rats in the germinated brown-rice group than in rats in the other two groups. These results suggest that intake of germinated brown rice may suppress increases in blood pressure associated with NaCl intake and also improve insulin sensitivity.

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The prevalence of type I allergies, including food allergies and atopic dermatitis is increasing worldwide. Chinese medicines and crude drugs have been used for treatment of these allergies ; however, the mechanisms of the treatment effects remain unclear. In the present study, we investigated the inhibitory effects of crude drugs on the degranulation of mast cells using the crude hot-water extracts of 83 types of crude drugs. Among the crude drugs, extracts from Ni-kei, fun-bo-i, ku-se-ki and on-ji most significantly inhibited the release of β-hexosaminidase in RBL-2H3 cells, with IC₅₀ values of 215.7, 79.1, 187.6 and 288.1μg/ml, respectively.

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Round bread fortified with conjugated linoleic acid (CLA) was developed to increase dietary intake of CLA. Specific volume, sensory evaluation, firmness and cohesiveness of the breads fortified with 2.0 g of CLA per 40 g of bread (CLA substitution rate : 60% of butter used) were similar to values of unfortified bread (control). CLA content of bread fortified during the baking process was increased by 7%, compared with bread fortified during the mixing process. CLA content during storage at 25°C and 5°C decreased gradually, while CLA content did not change during storage at -18°C. These results indicate that CLA-fortified bread can be manufactured using 0.5 to 2.0g of CLA per 40g of round bread.

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Japan is one of the top consumer countries in the world of chicken eggs at almost one egg per person per day. Chicken eggs contain eight essential amino acids in an ideal balance, giving an amino acid score that is as high as that for milk and beef (100) and the biological value that exceeds that of the latter foods (94). Furthermore, among animal-source foods, eggs are relatively rich in unsaturated fatty acids, fat-soluble vitamins and minerals such as phosphorus, calcium and iron. Despite these beneficial attributes, many consumers are worried about the relationship between chicken egg consumption and heart disease since chicken eggs are a high cholesterol food. Human studies in Japan reveal that consumption of egg yolk for 4 weeks did not result in an elevation of serum cholesterol level and there was no direct relationship between frequency of egg consumption and a risk of myocardial infarction in a 10-year follow-up study of 90,000 Japanese subjects. Rat studies provide evidence of the hypocholesterolemic action of egg yolk phospholipids and egg white proteins. Furthermore, feeding egg yolk phospholipids to rats with brain injuries and senescence-accelerated mice resulted in enhanced learning ability. These results indicate that chicken egg is an attractive food from the aspects of health promotion and nutritional function.

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It is known that eggs and egg components are frequently used for foods with high palatability; however, the effects of egg-derived molecules on emotional behavior have been largely unknown. We used the elevated plus-maze test in mice to investigate whether peptide derived from ovalbumin, a major egg white protein, has anxiolytic-like activity. We then found that a pentapeptide released from ovalbumin by trypsin exhibits potent anxiolytic-like activity with intraperitoneal and oral administration at a low dose comparable to diazepam, a general anxiolytic drug. Indeed, tryptic digest of ovalbumin exhibits anxiolytic-like activity after oral administration. In this review, we summarize the egg-derived molecules having anxiolytic-like activity. In addition, the mechanism underlying the anxiolytic-like activity of egg white-derived peptide was compared with previously described anxiolytic molecules.

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