The relation between the protein content of Inaniwa-udon and the respective hardnesses of the outer layer (H1) and all layers (H2) of boiled Inaniwa-udon was investigated, revealing a negative correlation between H2/H1 and protein content (r=-0.61). SEM cross-section images revealed larger cavities in the low-protein product (9.6%) than in the high-protein product (10.3%) for noodles from the same manufacturer. The relationship between H2/H1 and the cavity content of Inaniwa-udon and two other products followed a quadratic curve. When the cavity content of Inaniwa-udon exceeded 10%, the H2/H1 value fell.

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Sembei is a type of traditional Japanese rice cracker (Beika) produced from normal rice and is generally produced by roasting dried rice paste. The degree of swelling after roasting rice paste is generally thought to depend on the drying temperature, drying time and thickness of the rice paste. In the present paper, a general model of the water diffusion accompanying adsorption and desorption at the interface between air and the rice paste is presented, and the average concentrations of water under different drying temperatures and drying times are solved numerically using the model. The effect of drying temperature or thickness of the rice paste on the concentration profiles of water is discussed in terms of the model. The experimental results agreed with those of the numerical simulation and proved the applicability of the model. In the cases of low temperature drying and thin rice paste, the difference in water concentration between the surface and the center of the rice paste was estimated to be small. Low temperature drying seems particularly effective in giving homogeneous and soft swelling properties in the roasting of rice paste.

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In this study, edible films based on Alaska pollack surimi were successfully prepared and the effect of pH on film properties was determined. Films could be formed in the pH ranges from 2 to 4 and from 7 to 11. At pHs above or below the isoelectric point (pH 5.2-5.5), the edible surimi films increased in strength and became transparent. Elongation at break and water vapor permeability of the surimi films were not markedly influenced by pH. In acidic conditions, it was found that the myosin heavy chain within the surimi proteins was degraded and that formation of the films mainly involved hydrophobic interactions. In contrast, in alkaline conditions, not only hydrophobic interactions but also disulfide bonding played an important role in film formation. Those results indicated that the film-forming mechanism of surimi films is different in acidic and alkaline conditions.

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The effects of MTG, salt and polyphosphate on the physical properties of meat gel were studied by breaking strength testing and creep testing. For meat gel without salt and polyphosphate, the values of gel strength, strain, E₀ and τ of did not change upon addition of MTG, whereas for meat gel with 2% salt and 0.3% polyphosphate, the values of gel strength, strain, η_N and τ increased with an increase in MTG. For meat gel with MTG and 0.3% polyphosphate, the gel strength and strain values were not different from the values without MTG. Gel strength and strain increased with an increase in MTG, and E₀, η_N and τ increased with addition of salt to a concentration of 0.5%, after which they were constant. For meat gel with MTG and 2% salt, the values of E₀, η_N and τ did not change even with an increase in MTG or salt ; in fact, with addition of MTG, E₀ decreased. η_N and τ increased with an increase in polyphosphate. ε-(γ-Gln)Lys crosslinkages increased with an increase in MTG, especially at low concentrations of salt and polyphosphate. Based on the results, it was suggested that MTG could have functional property as a replacement for salt and polyphosphate.

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Frequency-dependent electrical impedance spectroscopy was used to characterize the intracellular and extracellular resistances, as well as the capacitance of the cell wall and cell membranes, of tea leaves during the primary drying process. At the beginning of the process, the extracellular resistance significantly decreased due to the leakage of electrolytes into the intracellular space as a result of pressurization by the spatula. When the drying process was prolonged, the extracellular resistance increased due to evaporation from the surface area of the tea leaves and the intracellular resistance also increased due to the decrease in the moisture content of the tea leaves. The capacitance of the cell wall and cell membranes decreased, with the assumptions that the temperature of the tea leaves had a negligible effect on the change in the capacitance and the cellular tissues were physical damaged. The deterioration and collapse of cellular tissues by pressurization was regarded as the main factor contributing to the decrease in the capacitance. These electrical behaviors observed in the primary drying process were affected by the material characteristics.

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The potent odorants of the Sweetio pineapple (Ananas comosus [L.] Merr. var. Marian-gold (MG3)) were examined by comparing them with the regular pineapple (Ananas comosus [L.] Merr. var. Smooth Cayenne (F-200)). The odorants in the pineapple extracts, which were pressed from fresh fruit, were separated by adsorption to Porapak Q resin. The total concentration of odorants in Sweetio pineapple extract was approximately twice that of regular pineapple, the upper, middle and lower parts containing higher odorants than their corresponding pars of the regular pineapple. 4-Hydroxy-2,5-dimethyl-3(2H)-furanone (furaneol) was found to be the most abundant compound in both pineapples. Sweetio pineapples contained higher proportions of methyl 3-(methylthio) propanoate, 4-methoxy-2,5-dimethyl-3(2H)-furanone (mesifurane), methyl hexanoate, 4-hexanolide, methyl 2-methylbutanoate and ethyl hexanoate than regular pineapples. In addition to these compounds, aroma extract dilution analyses and empirical assessments of odor units revealed that methyl 2-methylbutanoate and ethyl 2-methylbutanoate appeared to be primarily responsible for the characteristic odor of Sweetio pineapples. The enantiomeric ratios of both esters were determined for the first time in this study. Ethyl 2-methylbutanoate was 100% ee for the (S)-(+)-configuration in both pineapples. Methyl 2-methylbutanoate in both regular and Sweetio pineapples were 99.0% ee and 97.4% ee for the (S)-(+)-configuration, respectively. Additive experiments using authentic racemic chemicals revealed that methyl 2-methylbutanoate and ethyl 2-methylbutanoate were the key odorants responsible for the “extending”, “refreshing” and “fruity” notes of the extract, which, on the basis of sensory evaluation, were found to be significantly more intense in Sweetio pineapple extract compared to regular pineapple extract.

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Carbohydrate composition in the tubers and flowers of apios (Apios americana Medikus) were investigated. The approximate mono- and oligosaccharide, starch and cell-wall polysaccharides content per 1g triturated samples were 188mg : 479mg : 36mg for tubers, and 192mg : 179mg : 131mg for flowers, respectively.
Analysis of the mono- and oligosaccharide fractions by gel-filtration chromatography and high-performance anion-exchange chromatography showed that 86-90% of the fractions from tubers were glucose and sucrose and most of the fractions from flowers were glucose and fructose. In addition, 14-10% of the fractions from tubers were oligosaccharides with degrees of polymerization exceeding 3, including raffinose and stachyose. Scanning electron microscopy of starch granules isolated from apios tubers revealed that they were egg-shaped and approximately 10.6μm in size.
The cell walls of tubers and flowers contained pectic compounds, hemicellulose and cellulose at a ratio of 6 : 43 : 51 and 7 : 36 : 56, respectively.
The results of the methylation analysis of these polysaccharide fractions indicated presence of rhamnogalacturonan as well as the neutral sugars, arabinan, xylan, galactan, arabinogalactan, xyloglucan and cellulose in the cell walls of tubers and flowers.
The findings were discussed relative to the carbohydrate concentrations in the soybean, azuki bean, potato and sweet potato.

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Saki-ika, made from raw squid, is soft in texture and white in color. This whiteness is an important parameter for evaluating the quality of saki-ika. However, the color of saki-ika made from flying squid, Ommastrephes bartrami, turns from white to brown when exposed to air and is also influenced by temperature. The purpose of this study was to clarify the conditions under which browning occurs in soft saki-ika.
It was found that the color of packaged saki-ika turned from white to yellowish brown after exposure to oxygen, or to red under oxygen-free conditions, and that this was dependent upon increased storage temperature. Furthermore, the red color of saki-ika is accelerated under oxygen-free conditions and inhibited when oxygen levels are increased.
In addition, the effect of different processing conditions on the extent of browning in saki-ika stored was investigated. During storage, the color of raw unblanched saki-ika samples changed markedly and the a* values (intensity of the red color) were observed to increase more than twice that of blanched and blanched-dried samples irrespective of raw meat species. These findings indicated that the compounds, or their precursors, that are responsible for browning are already present in the raw meat. Furthermore, these compounds appeared to increase in response to the action of certain enzymes during storage in the raw meat sample system, and that these enzymes can be inactivated by heating.

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The following study examined different aspects associated with the sorting of different rice harvests. Specifically, we assessed : (1) Various aspects related to the heading of rice, focusing on the differences in grain size when heading is early and grain size is large, to decreased grain size when heading is late. (2) Physicochemical properties and their relationship with the quality and size of grain. (3) The predominance of large grained cereals arising from selective cultivation as a food source. (4) The relationships between the physicochemical properties of rice and grain size by principal component analysis.

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Factors affecting the variation of mineral components of apple fruit were studied. The following 9 elements were measured in apple fruit : Na, K, Mg, Ca, Fe, Mn, Cu, Zn, and P. Dwarfed ‘Sansa’ tree apples were grown in 2001 in an experimental orchard at the National Institute of Fruit Tree Science in Morioka. The effects of sunlight on the mineral content of apple fruit were investigated. A simple estimation of the sunlight exposure of apple fruit was carried out using Y-type recording film for measuring the total integrated solar radiation. Fruit insolation of 75 apples was measured from two directions (east and west) and inside and outside of the crown. The fruit weight and degrees Brix of apple fruit grown outside the crown were significantly higher than those grown inside. Significant correlations with solar radiation were observed for fruit weight and degrees Brix. Significant negative correlations with solar radiation were observed for the ash, K, Ca, Zn, fruit weight, and degrees Brix. The concentration of minerals in apple fruit grown inside was higher than in fruit grown outside of the crown. The concentration of minerals was higher in apples grown on the shade side than in apples grown on the sunny side. No significant differences in mineral concentrations were observed between fruit grown on the east and west sides. These results suggest that sunlight exposure for dwarfed trees was of equal importance as the fruiting direction for the dispersal of sunlight.

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