Heat penetration into milk-wheat flour paste in a retortable pouch and its browning reaction rate during heat processing by a steam retort were investigated. Heat penetration curves of the paste packed in a pouch followed approximately single logarithmic curve. When the concentration of wheat flour in the paste was 5% or more, the slope of heat penetration curve (m) and lag factor (j) calculated from the theory of conduction in an infinite slab agreed with experimental results. Heat penetration was, therefore, governed mainly by conduction for the paste containing wheat flour more than 5%. The rate of browning reaction of the milk-wheat flour paste expressed by the decreasing degree of whiteness obeyed the first order reaction. The activation energy of this reaction was 26 (Kcal/g-mol) and the dependence of the reaction rate constant (k) on temperature was 1.17×1012 exp (-13085/T).

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The emulsifying capacity (EC) and emulsion stability (ES) of untreated soybean protein isolates decreased to a minimum level in the isoelectric region (around pH 4.5) regardless of protein concentration, while those of the acetylated proteins showed no decrease in that region and increased from acidic to alkaline region monotonously. The ES of succinylated proteins showed a behavior similar to that of untreated proteins, however, the minimum point of the ES shifted from pH 4.5 to 3.5 and exhibited high ES at around pH 7. The ES of soybean protein isolates varied in a complicated manner with the degree of acylation. Acetylation over 95% of available amino groups of proteins improved the ES at pH 7, especially succinylation of over 85% increased the ES at pH 7 as much as 2.5 times higher than that of untreated proteins. Acetylation and succinylation improved the ES at pH 4.5 by 40% and 25% respectively, Succinylation between 30 to 70% increased the ES at pH 3.5 by 40%, but the succinylation over 90% decreased the ES again toward 0. In the case of acetylated proteins, the simple correlation between protein solubility and the ES was not necessarily observed.

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The textural properties of Curdlan 13140 (PS)-starch gels were investigated by using a Rheometer. The gel was prepared by heating an aqueous suspension of PS, starch and sucrose at 100°C for 1hr. The gel formulated with 2% of PS, 8% of starch and 20% of sucrose showed little syneresis, though a gel prepared with PS alone showed a remarkable syneresis. The gel strengths of PS-starch gels were lower than that of gels contained no starch. Waxy corn starch was mostly used, with respect to stability of the product. The gel strength of PS-starch gel was increased by increasing the contentration of PS and by extention of the heating time, and was decreased by increasing starch within the concentration range from 0 to 20%. The textural properties of the PS-starch gel showed an intermediate textural properties of PS and starch gel. The gel strength of PS-starch gel increased with the addition of sucrose at the concentration level less than 15%.

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In order to develop a practical use of Curdlan 13140-starch gel, a Uiro like confection (a kind of a gelatinous sweetened rice cake) was designed and its processing conditions were investigated. The textural properties of PS-starch gel were varied by addition of other materials. For instance, the gel added with 2% of instant coffee powder became tough and elastic, while the gel added with either 20% of milk or mushed red beans ("An" in japanese) became weak and easily shattered. The gel strength of PS-starch gel was remarkably decreased when the temperature of gel increased. In the case when the gels were stored at 10°C or 20°C for 4 weeks, the changes of gel strength were small, but Young's Moduli were increased gradually with the prolonged storage period of gels.

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Ultraviolet difference spectra were measured to study the interaction between yeast protein (SCP) and sodium dodecyl sulfate (SDS). Gel filtration chromatography was also carried out with SCP preprared from different SDS concentrations and concentrated alkaline solutions of SCP. The obtained results were summerized as follows: 1) The difference spectra obtained from SDS concentration 2-5% against SCP suggested that denaturation occured in the protein. 2) The observation of gel filtration chromatogram revealed that lower molecular weight components of SCP increased with increasing SDS concentration. This accorded with the results of difference spectra. 3) Gel filtration chromatogram of concentrated alkaline solutions of SCP showed that NaOH caused further disintegration of the protein into molecule of approximately 10, 000-20, 000 molecular weight. Above results indicated that the disintegration of SCP was necessary for the application for food use by spinning method.

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The physical and chemical properties, evaporated residue, carotenoid content and total tocopherol of essential oils of Satsuma mandarin (Citrus unshiu Marc.), Natsudaidai (C. natsudaidai Hayata), Kabosu (C. sphaerocarpa Hort.), Valencia orange (C. sinensis Osbeck), Marsh grapefruit (C. paradisi Macfad), Ruby Red grapefruit (C. paradisi Macfad) and Temple orange (C. temple Hort.) were examined. No remarkable differences in specific gravity and refractive index were found among the citrus oils. Satsuma mandarin oil showed the highest value in the amount of the evaporated residue, carotenoid and tocopherol among the examined samples. Citrus oils showed strong antioxidative activity due to the presence of carotenoid and tocopherol determined by TLC as total tocopherol.

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The antioxidative activities of water, ethanol and ether-soluble fractions from 24 Japanese pharmacopoiea crude drugs on methyl-linolenate were investigated in the comparison of BHA. The results indicated that the presence of strong antioxidative substances in the water-, ethanol-and ether-solble fractions obtained from both Caryophylli Flos and Glycyrrhizae Radix.

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Crude leaf protein concentrates (LPC) were precipitated by adjusting the pH of the leaf extractant (pH 7.2) to 3.8 and this precipitate was washed with 90% acetone for several times. The color of dried LPC was light gray and the average yield was 1.75g per 100g fresh leaves, which correspounded to about 30% of the total proteins constained in the leaves. The composition of LPC was as follows: protein: 88.4%, lipid: 1.3%, ash: 2.6% and water: 7.0%. The result of amino acid analysis showed that the content of methionine was low but the amino acid pattern of the LPC gives fairly high level of the essential amino acids than that of the FAO reference protein. Mineral composition of the two LPC preparations revealed marked differences between samples as in the case of Wang and Kinsella.

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