The effect of mixing of soy proteins (SPs) with sodium caseinate (SC) on emulsion stabilizing property of SPs was studied using a technique of ultrasonic emulsification. Emulsion stabilizing property of acid-precipitated soy proteins (APP) was improved remarkably by mixing of APP with SC. This phenomenon was presumed to be caused mainly by 11S protein fraction of APP. Effect of reducing treatment of SPs on stabilization of the emulsions was especially notable in the case of 11S protein fraction.

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Stabilization mechanism of a series of protein stabilized emulsions was investigated by determining oil globule size distribution and protein load^* of emulsions. Oil globule size distribution in the acid-precipitated soy protein (APP)-stabilized emulsions was shifted by mixing APP with sodium caseinate (SC) toward larger range in the case of agitation emulsification, and shifted toward smaller range in the case of ultrasonic emulsification, respectively. These results agreed with change in emulsion stabilizing property of APP caused by mixing APP with SC. In both ultrasonic and agitation emulsification, surface of oil globules in the emulsions stabilized with the protein mixtures was coated with SC alone. Protein load of SC in the emulsions stabilized by sonication was found to be generally larger than that in the emulsions stabilized by agitation method. ^*Amount of proteins adsorbed onto unit surface area of oil globules, mg/mm².

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Japanese persimmon cv. Sanja were harvested and the compositions and other attributes were measured at regular intervals throughout the growing season. Color development in peel was closely related with the color value "a" measured with the color difference meter. The color value "a" increased remarkably after October 10th. The color index by the color chart was correlated with the color value "a" and was a useful indicator for maturation. Soluble tannin content in the fruit was between 3 and 4%, till September 20th and then decreased gradually. Soluble tannin contents in the fruit harvested on November 10th (ordinary harvest maturity) and 20th were approximately 1.5 and 1.0%, respectively. Fructose and glucose were relatively constant untill October 1st, whereas sucrose markedly increased throughout the experiments. The concentrations of these sugars were 3.3, 3.9 and 4.4% on November 10th. It was not reliable to estimate the sugar content from the reflactive index value. Though the flesh firmness was relatively constant untill October 1st, it decreased rapidly thereafter along with the loss of the pectic substances. Moisture, crude fiber and total ascorbic acid contents were tend to decrease, while no significant changes were observed in crude protein, ash and titratable acidity.

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Constituents of Grifola frondosa (Fr) S.F. Gray, which is on market as "Maitake" were studied. We traced change of constituents in the stage of fruit body formation of Grifola frondosa. The results are as follows: (1) Water content was almost similar during fruit body formation. Crude protein and crude ash decreased as growing, but crude fat slightly increased. (2) K, Na, Ca, Mg, Fe, Cu, Zn and Mn were measured. The content of K was the highest, then Mg, Ca and Na were contained in larger amount than other elements. (3) Seventeen kinds of free amino acids were determined. The content of Glu was the highest. (4) Mannitol was determined. The content of mannitol was larger in primordium than matured fruit body. (5) Trehalose and glucose were determined. The content of trehalose increased as growing. The content of glucose increased formic acid, malic acid, citric acid, succinic acid, oxalic acid and fumaric acid were determined. Malic acid existed in the largest amount, followed by pyroglutamic acid, fumaric acid and succinic acid.

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Profiles of the time-dependent liberation of free amino acids and oligopeptides during the enzymatic digestions of antarctic krill (autolysis, autolysis in the presence of commercial proteinase and digestion with commercial proteinase alone) were determined by an automatic amino acid analyser and convenient colorimetric methods. Glutamic acid, alanine, valine, leucine, lysine and arginine were preferentially liberated together with oligopeptides by autolysis, while release of glycine and proline was found to be scarce. Autolysis in the presence of commercial proteinase markedly enhanced the accumulation of almost all the amino acids and oligopeptides having the glutamic acid, aspartic acid, glycine and lysine residues. The effect of added enzymes on the profiles of the amino acid liberation was shown to be sinergistic rather than additive, since the digestion with commercial enzyme alone could hardly release free amino acids except for oligopeptides. Taurine, one of the predominant non-protein amino acids in the digest, was kept in constant levels through the digestion periods, indicating that this amino acids may be available for the estimation of product yields in processing. The convenient colorimetric methods consisting of the selective coloration of free amino acids with Cd-ninhydrin and of free amino groups with trinitrobenzenesulfonic acid were proved to be useful for monitoring the digestion process.

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A rapid and simple method for quantitative determination of diethylene glycol (DEG) added to wine with range between 0.001% and 10% was developed. An assay solution for GC analysis was prepared as follows: 1g of wine, 1ml of 1% ethanol solution of tetraethylene glycol dimethyl ether (internal standard), and 15g of anhydrous sodium sulfate were mixed well in a mortar, and then stand for ten minutes. The mixture was extracted twice with 10ml of ethanol. The extract was condensed to ca. 1ml by evaporation in a hot water bath. GC analyses were carried out with a glass column packed with PEG 20M at 200°C isothermal condition. DEG content was determined from the calibration curve. When wine samples with 0.005, 0.05, 0.5, and 5% of DEG, were ana- lyzed five times for each sample respectively, recoveries and coefficients of variance were 67.9% and ±4.3%; 98.7 and ±3.0%; 98.9% and ±1.2%; 99.9% and ±2.1%, respectively. The concentration limit for detection of DGE by GC-MS was 0.01%.

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Comparison of volatile sulfur compounds in wasabi, horseradish and black mustard hydrolysates by gas chromatography with FPD were investigated. (1) Thionaphthene and phenyl isothiocyanate were used as internal standards. Allyl isothiocyanate (itc) content was dominant in every material. Iso-propyl itc, sec-butyl itc, n-butyl itc, 4-pentenyl itc, 5-hexenyl itc, unknown compounds No. 13 and No. 14 had larger values in wasabi than in the other materials, especially latter 2 compounds. (2) β-Phenethyl itc content was larger in horseradish than in the others. In horseradish grown in China, 3-butenyl itc and β-phenethyl itc had larger values than the one grown in Hokkaido. (3) Unknown compound (Peak No. 15) was detected only in black mustard. (4) Allyl itc contents were about 1% (w/w) in 3 materials. Ratios (%) of β-phenethyl itc content to allyl itc content were 19.19 in horseradish, 0.938 in black mustard, and 0.134 in wasabi, respectively.

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The "Sunki", one of the peculiar Japanese pickles produced in Kiso district, Nagano pref. is pickled without salt under a lower temperature by lactic acid fermentation, then dried and preserved throughout the year. Sunki-pickling method is considered to be available for preserving green vegetables. In this paper, the authors intended to make leaves of Gishigishi (Rumex japonicus Houttuyn, a sort of Japanese wild glass) into reserving food by means of Sunkipickling method. The general nutrients in the raw glass were determined comparing with those in some cultivated vegetables. Then briefly cooked Gishigishi was pickled for 7 weeks withous salt, and the crude protein, free amino acid compositions, total amino acid compositions in the pickles and free amino acid compositions in the pickling juice were determined each week. And sensory evaluation was carried out for all produced pickles. The following results were obtained. (1) The nutrient contents in Gishigishi were superior to those in some cultivated vegetables. (2) The most suitable condition of Sunki-pickling method for Gishigishi to maintain nutrients and good taste in it was 4 weeks at 5°C. (3) Gishigishi could be preserved as reserving food by means of Sunki-pickling method.

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The determination of potassium in two red wines and two white wines was carried out by using an ion-meter. The results were compared with those obtained by an atomic absorption spectrophotometer. The wines were diluted with distilled water to give the concentration of less than 2% of alcohol, the higher concentration of which interfered with the determination. The potassium contents obtained by an ion-meter were very similar to those by an atomic absorption spectrophotometer. The results showed that the method by an ion-meter provided simple and reliable determination of potassium in wines.

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In Pro-Xan II process, green juice (GJ) extracted from leaves is heated first to 60°C, cooled and centrifuged. The supernatant i.e. clear brown juice (CBJ) is reheated to 80 to 85°C to prepare white leaf protein concentrate (LPC). This paper deals with solubility and stability of proteins in GJ and CBJ derived from alfalfa, white clover and Italian ryegrass. The pH solubility profiles from the three crops are almost similar in GJ but not in CBJ. The stability of protein in GJ and CBJ was low, depending upon the temperature and pH in storing and it is deeply related to the recovery of LPC. These results may suggest that LPC should be prepared with a keen attention to kinds of crop and to storing temperature and/or pH of GJ and CBJ.

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