The effect of organic solvents (dimethyl sulfoxide, dimethylformamide, dioxane and glycerol) on hydrolysis of several glucosides by β-glucosidase was observed.
When salicin was employed as substrate, all the solvents tested (each 50%, vol/vol) inhibited the hydrolysis. When cellobiose was used as substrate, dimethyl sulfoxide exhibited inhibition, while dioxane stimulated the reaction and dimethylformamide had little effect. When substrate was genistin, which is practically insoluble in water, the hydrolysis was much enhanced in the presence of dimethyl sulfoxide, dimethylformamide, or dioxane. The effect of dimethyl sulfoxide was the greatest among them. Dimethyl sulfoxide showed maximum accerelation at 40% (vol/vol). Glycerol always showed strong inhibition regardless of the substrate.

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Nonenzymic browning reactions of casein (C) or N-acetyl casein with various phenolics including flavonols were studied by model systems kept in pH 6.8.
The degrees of the browning at 470 nm of each reaction product were as follows: C+myricetin>C+quercetin>C+catechin>C+phloroglucinol≥C+azaleatin>C+caffeic acid>C+dihydro-quercetin>C+chlorogenic acid>C+protocatechuic acid. In C+rutin, C+quercitrin, C+rhamnetin and C+luteolin, the browning was weak. These results suggested that the browning of casein was strengthened by both hydroxyl groups at 3- and 7-positions on flavone ring possessing hydroxyl groups at 3'- and 4'-positions.
Available lysine decreased by 18% for reaction product (C₁) prepared by heating casein with quercetin and 10% for reaction product prepared by mixing casein with browned solution from quercetin which was heated previously. N-acetyl casein heated with quercetin browned, too. These results suggested that a part of the browning of casein might be given without the interaction of ε-amino groups of casein with quercetin, its oxidation products or brown pigment produced from these compounds.
In elution patterns of C₁ and the mixture composed of casein and browned solution from quercetin on Sephadex G-150 column, the peaks of nitrogen and brown color overlapped. From this result, it was considered that casein molecule combined strongly with quercetin, its oxidation products or brown pigment produced from these compounds.

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To investigate the aroma difference of green tea caused by cultural conditions, analysis of aroma concentrates of green tea and fresh tea-leaves (excess fertilized, standard fertilized, no fertilized and cultivated in a vinyl-house under standard fertilizer application) was accomplished. Excess fertilized green tea, which had a strong and lasting heavy aroma lacking of briskness, abounded with higher boiling components of heavy aroma (i.e. β-ionone, 5, 6-epoxy-β-ionone, dihydroactinidiolide, indole).
On the other hand, cis-3-hexenyl acetate, cis-3-hexenol and cis-3-hexenyl hexanoate which are responsible to briskness were the less proportion. In the aroma concentrate from the green tea cultivated in a vinyl-house, linalool, cis-3-hexenyl hexanoate, cis-jasmone and indole were the less proportion, β-Ionone, 5, 6-epoxy-β-ionone and dihydroactinidiolide were much more in quantity when compared with that of standard cultivated one. These facts seemed to explain the results of organoleptic evaluation.

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Konjac mannan (KM) was gelatinized under several conditions, and the amount of acetyl group released by saponification during the induction period was determined. The amount was almost constant regardless of the reaction temperature, though the length of induction period decreased with an increasing temperature. The amount increased with the decrease in concentration of KM. Acetyl groups of KM were released completely at a concentration of about 0.5% of KM (the minimum concentration at which the gel can be formed). The amount increased with the increase in concentration of hydroxy ion in the reaction mixture. The variation profile of the degree of deacetylation with the concentration of hydroxy ion, however, was almost independent of the gelatinizer used. These findings confirmed the previously proposed conclusion that the deacetylation is indispensable for the gelation of KM as an induced reaction.

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Experiments were done to detect lysinoalanine (LAL) in 16 commercial soy sauces^*, heat treated defatted soybeans and wheat. Free LAL and LAL in protein linkage were determined by an amino acid analyzer. As little as 30ppm of LAL in soy sauce, and 40ppm in the materials can be determined by this method. The experimental results demonstrated that LAL was not detected in the soy sauce, the heat treated defatted soybeans and wheat.

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Neutral lipids were isolated from Aspergillus oryzae, and chemical composition of the acyl lipid classes was analysed.
Neutral lipids consisted of hydrocarbon, sterol ester, fatty acid ester, triglyceride, free fatty acid, 4-methylsterol, 4-demethylsterol, 1, 3-diglyceride, 1, 2-diglyceride and three unidentified lipids; triglyceride and free fatty acid were predominant among them. The ratio of ethyl ester and methyl ester detected in fatty acid ester was approximately 58:42.
Main component fatty acids in neutral lipid, triglyceride and diglycerides were linoleic, oleic and palmitic acids in decreasing order. Sterol ester and fatty acid ester possessed a large quantity of linoleic acid. In free fatty acid a higher proportion of palmitic acid was observed than in other lipids.
As for the positional distribution of fatty acids in triglyceride, linoleic, oleic, palmitic and stearic acids were located at 1-C and 3-C of the molecule; unsaturated ones (oleic and linoleic acids) were predominant at 2-C.
Molecular species of triglyceride from monoenoic to hexaenoic type were found. Tetraenoic type (palmityldilinolein, palmityloleyllinolenin etc.) was the principal.

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The essential oils from the fruits of Lindera strychnifolia (Sieb. et Zucc.) F. Vill., grown in Kumano (Mie prefecture) and Hirakata (Osaka prefecture), have been studied. The essential oils were obtained by steam distillation from the mesocarp and seed. The constituents of the essential oils from the mesocarp and seed were respectively investigated by column and gas chromatography, infrared, ultraviolet, mass and nuclear magnetic resonance spectrometry to determine thirty three compounds. The major components in the mesocarp oil were mono- and sesquiterpene hydrocarbons such as α-pinene, β-selinene, δ-cadinene and γ-cadinene, while those in the seed oil were furanosesquiterpenoids such as lindestrene, lindenenyl acetate and lindenenol. The contents of α-pinene, lindenenyl acetate, δ-cadinene and γ-cadinene were rich in the Kumano's oil, while that of β-selinene was rich in the Hirakata's oil.

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Textural characteristics of gelatin, agar-agar and egg-white gels were evaluated by sensory terms. Eight 7-point rating scales corresponding to the fundamental textural characteristics of gel foods were used.
Rating scales could be classified into three categories: rating scales useful for describing the differences in texture of gels prepared from the same gelling agent, those useful for differentiating the gels from the different gelling agents and those useful for both.
Sensory “hardness” was highly correlated with Texturometer hardness, following Fechner's logarithmic law, and also with breaking strength. Sensory “brittleness” and “springiness” were correlated with deformation at the breaking point.
Instrumental parameters which correlate with the sensory parameters important for differentiating the gels from the different gelling agents could not be found so far as this study concerns.
As conclusion, sensory evaluation under controlled conditions is valid and useful for characterizing the textural properties of gel foods.

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For the production of textural protein food material from Krills, freezing denaturation process like “Kori dofu” was tested. The flesh of the krills was mixed uniformly with homogenizer or kneader and centrifuged. The resulting precipitate was again homogenated with same volume water and freezed at -7.5_??_-15°C, pH 7.0.
A sodium salt or calcium salt addition, pH treatment (sample was adjusted to pH 10 at least and returned to the near neutral pH) and aerobic condition stimulated the homogenate to strengthen but supernatant at preparing the precipitate, peroxide addition and anaerobic condition depressed them to do so.
N-Ethylmaleimide modification revealed that SH residue of protein played a major role in the freezing denaturation in a similar manner as “Kori dofu”.

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When 3-hydroxy-2-pyrone (HP) was allowed to react with ninhydrin, a yellow coloration occurred. The molar absorption coefficient of HP in the ninhydrin reaction was 6.12 ×10³ at 440nm, whereas that of L-proline was 5.64 ×10³. When HP was analyzed by an amino acid analyzer (Hitachi KLA-5), the peak of HP (pK ₁ 1.62) appeared ahead of the peak of L-aspartic acid (pK₁ 1.87). HP was found to be separated on the cation exchange resin and could be determined by the amino acid analyzer from the relation between HW value of the peak and mmol amount of HP. The recovery of HP from the column was 99%.
When dehydroascorbic acid (DHA) was heated in aqueous solution (pH 2) in a boiling water bath and the solution was analyzed by the amino acid analyzer, the peaks of 2, 3-diketogulonic acid, DHA and HP with one unidentified peak were obtained. By heating for 30min, 0.53mmol of HP was formed from 1mmol of DHA.

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