Mochi, a unique product in Japan, shows typical visco-elastic behavior after cooking. Four key preparative conditions of mochi were examined to a method employing shiratama flour which prepared by wet milling of waxy rice.
a) Steaming a large lump of shiratama flour dough was better than boiling small lumps because the mochi of the former always resulted in a constant apparent viscosity value, measured with a penetrometer. b) Dough steamed for 15min was kneaded and forced into a polyvinylidene chloride film casing or a hard rectangular case through a hand-worked extruder. c) The molded mochi in these containers was cooled in a refrigerator for more than 48 hr. Since the apparent viscosity increased sigmoidally (10⁴_??_10⁵ poise) with an elapse in cooling time, the mochi cake become easier to cut for testing with a relaxometer on successive examinations. d) The optimum concentration of the solid matter was about 45%, for ease of handling. Thus, this study established a moisture determination method for waxy rice products. The important feature was the pre-drying in which the mochi lump was puffed up between heated iron plates.

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Stress relaxation of shiratama mochi cake was rapidly determined by a self-made simple shear type, parallel plate relaxometer. After correction of the apparatus and checking the linearity of the viscoelasticity of mochi, relaxation moduli of 43.8_??_47.0% mochi were measured at softening temperature range of 32_??_54°C. G (t) curves in the range of 10⁶_??_10⁴ dyn/cm₂ vs. 10^-1_??_10³ sec showed rather flat curves at about 30°C that rapidly relaxed at over 40°C. They corresponded to E_r (10) of the order of magnitude of rubbery plateau or transition regions and flow region of linear amorphous polymers. The six elements in the mechanical model of 44.5% mochi were calculated from the G (t) curves at every examined temperature. G₁, G₂ and η1, showed downward trends, inversely proportional to rising temperature. Master curves were obtained by application of the method of reduced variables. Activation energy _??_H, however, calculated from the temperature dependence of the shift factor a_T showed a very high value. As a criterion for applicability to WLF Eq., the constant, C₁⁰ differed from the universal value; therefore, the relaxation spectrum was not examined.

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The extract of dried Shiitake (L. edodes) was fractionated to peptide-rich fractions and some other fvactions by ion-exchange resins and gel-filtration on Sephadex G-15. Subsequent quantitative treatments and further fractionations of the peptide rich fractions by ion-exchange resins revealed that about 20% of total nitrogen of the extract was attributable to oligopeptides. The constituent amino acids of the peptide rich fractions were mainly glutamic acid, cystine or cysteine, aspartic acid, glysine, and serine. Lentinic acid and N, N'-bis-γ-glutamylcystine were identified as major components of the peptide-rich fractions, and some other components were also identified.

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The administration of a diet containing 250 ppm of PCB (Aroclor 1248) to carps caused increased TBA values and decreased amounts of glutathione, vitamin E and substances reactive to 1, 1-diphenyl-2-picrylhydrazyl in the hepatopancreas.
In addition, the treatment of carps with the same diet caused a significant elevation in the activities of both glutathione peroxidase and glutathione reductase in the hepatopancreas, whereas no change was observed in γ-glutamyltranspeptidase activity.
Lipid peroxidation occurred in the 9000×g supernatant or microsomes of the hepatopancreas in the presence of the NADPH-generating system and Aroclor 1248 at concentrations of 10^-6M and 10^-7M. On the other hand, Aroclor 1248 inhibited the peroxidation at 10^-3M and 10^-4M. In vitro lipid peroxidation in the presence of Aroclor 1248 required the NADPH-generating system.
Aroclor 1248 inhibited NADPH-cyt. c reductase and glucose-6-phosphatase in vitro at concentrations above 10^-5M in the hepatopancreas microsomes.
Aroclor 1248 administration increased the amount of 1-anilinonaphthalene-8-sulfonate (ANS) bound to the carp hepatopancreas microsomes. The in vitro addition of Aroclor 1248 enhanced the binding of ANS to the hepatopancreas microsomes, and this was more potent at higher concentrations of Aroclor 1248 than at lower concentrations.
The mechanism of lipid peroxide formation in the hepatopancreas of carp ingesting Aroclor 1248 was discussed.

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Gas chromatographic headspace analysis has been applied to Satsuma Mandarin juice before and after storage by means of precolumn technique. The precolumn (Ø 3.5×90mm) was prepared by packing ca. 130mg of Tenax-GC.
The aromagrams consisting of forty-six components were obtained. Then, the difference of aromagram between fresh and stored juice was examined. Five compounds greatly increased during storage and four of them were presumed to contribute to off-flavor. Significant decreases of five compounds were observed, while d-limonene was fairly stable in juice.

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Five flavonoids were isolated from seeds of tatari buckwheat (Fagopyrum tataricum Gärtner). By the spectral analysis and the direct comparisons of the isolates and their hydrolyzed products with the authentic flavonoids, they were assigned as quercetin, kaempferol, kaempferol 3-rutinoside, rutin and quercetin 3-rutinoside-7-galactoside respectively.

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Under UV-irradiation in a neutral medium (E)-3'-acetoxy-2'-hydroxy-2', 3'-dihydro-α-ionone afford-ed a mixture of (Z)-3'-acetoxy-2'-hydroxy-2', 3'-dihydro-α-ionone, 3'-acetoxy-retro-γ-ionone, (E)-3'-acetoxy-β-ionone and 10-acetoxy-1, 3, 7, 7-tetra-methyl-2-oxabicyclo[4. 4. 0]deca-3, 5-diene, in acidic medium a cyclized compound, 10-acetoxy-5-me-thoxy-1, 3, 7, 7-tetramethyl-2-oxabicyclo[4. 4. 0] dec-3-ene, and in basic medium a mixture of two cyclized compounds, 10-acetoxy-3-hydroxy- and 3, 10-dihy-droxy-1, 3, 7, 7-tetramethyl-2-oxabicyclo [4. 4.0] dec-5-ene.

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