To study the preservative property of various shredded vegetables treated by steam heating, cabbage, cucumber, The respiration rate, chemical composition in terms of reduced ascorbic acid and total soluble sugar, and quality stability of broccoli harvested in autumn (November), winter (January) and spring (April) were investigated during storage at room temperature or 15°C. A nearly second-order regression equation (Y = a +b^*T + c^*T²) with a high relative coefficient (R=0.989-0.996) was established for the respiration rate (mg CO₂·kg^-1·hr^-1) (Y) and temperature (°C) (T) of broccoli. At the same temperature, broccoli harvested in winter showed a higher respiration rate than that harvested in autumn. Broccoli harvested in winter had two times as much total soluble sugar content as that harvested in autumn or spring. For broccoli harvested in autumn and stored at room temperature, its reduced ascorbic acid, total soluble sugar and chlorophyll contents decreased markedly with floret yellowing. These indicate that broccoli harvested in autumn and stored at room temperature does not retain good quality. The reduced ascorbic acid and total soluble sugar contents of broccoli harvested in winter remained unchanged for 6 days, suggesting that the broccoli retains good quality during storage at room temperature. Similarly, broccoli harvested in winter and stored at 15°C showed had much better quality stability than broccoli harvested in the other seasons. For the same harvestseason, the quality of broccoli was successfully maintained during storage at low temperature. Moreover, correlations among the respiration rate, chemical composition and quality stability of broccoli were observed, that is the lower the respiration rate, the higher the reduced ascorbic acid and total soluble sugar contents and the higher the quality stability.

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The thermophysical properties of five kinds of foods (sucrose solution, sodium chloride solution, milk, ground pork, and whole milk powder) were measured by the transient heat flow method using a probe at 20°C. In this study, a new method of estimating three kinds of thermophysical properties, namely, thermal conductivity, thermal diffusivity, and specific heat, was proposed. The measured data for the temperature changes of the probe inserted in the sample were fitted to an approximate solution of the heat conduction equation, and the values of two parameters in the solution were determined. For a long period of time (more than 30 seconds), the measured results agreed well with the results calculated from the solution. Using the obtained values for two parameters, the thermal conductivity and the thermal diffusivity of the sample were determined. The specific heat of the sample was estimated by substituting the thermal conductivity and, thermal diffusivity of the sample, and the density of the sample or the bulk density of the sample packed bed into the definition equation of thermal diffusivity.

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Packaging has a significant effect on strawberry damage. In conventional 2-layer packaging, strawberry damage occurs rapidly and extensively. Packaging holding strawberries horizontal on a sponge cushion, although expected to reduce such damage, has turned out instead to incur nearly the same degree and speed of strawberry damage as conventional 2-layer packaging. We have proposed packaging that holds strawberries in a vertical position, and have found that such an arrangement minimizes contact between strawberries. Moreover, our proposed packaging decreases damage area to 30% that of conventional packaging. Our proposed packaging maintaining strawberries in a vertical position thus effectively decreases damage during transport. Damage as such was concentrated on the equatorial portion and calyx of strawberries. In a study of damage reduction with three types of sponge material, we found that damage was lowest with rubber sponge having a density of 8.7×10^-2 g·cm^-3 and a compression stress of 2.69×10^-2 MPa at 25% distortion.

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Plant sterols are natural dietary components whose lowering effect on serum cholesterol level has been well documented. The purpose of this study was to determine the effects of plant-sterol-supplemented processed rice on serum of cholesterol level. In the determination, a double-blind, placebo-controlled study was conducted using a 3-group parallel protocol. The subjects comprised 33 healthy Japanese males and females with a total cholesterol level of 234. 6± 24.6 (mean±SD, mg/ml). They were given a daily ration of rice balls prepared from plant-sterol-supplemented rice containing 1.46 and 2.25 g of plant sterol for 4 weeks. Serum total cholesterol was reduced by 4.6% in the 2.25 g/day plant-sterol (as β-sitosterol of about 968 mg/day) group (p<0.05). As for LDL cholesterol level, such reduction was observed in 4.3%. In all the groups, no significant change in the level of HDL-cholesterol, triacylglycerol, RLP-cholesterol, VLD-lipoprotein, LD-lipoprotein or other kinds of apolipoprtein and biochemical parameters. In addition, no remarkable abnormality was observed in the subjective and objective examination of what symptoms. These results indicate that plant-sterol-supplemented processed rice is useful in supporting healthy eating habits for reducing serum total cholesterol level.

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