Supernatant of coagulated soymilk on Tofu processing have been termed Yu in Japanese, and have been main waste of Tofu factory. The recovery of protein from the waste Yu water is expected to be effective for reduction of waste treatment facilities and the recovered proteins should be utilized as food materials. The Yu fraction was suggested to contain some factors which effect on growth of rats, since the protein efficiency was negative. Therefore, on the base of preliminary experiment as to solubility of the Yu in water and ethanol, the Yu was fractionated as follows; water insoluble fraction (ISF) from water dispersion of the Yu recovered on Tofu processing, alcohol insoluble fraction (AIF) from the water soluble fraction in 50% ethanol, upper layer (UL) and lower (LL) layer by saturation of the 50% ethanol soluble fraction with ammonium sulfate, and the floating fraction (FF) were obtaind. Main ISF and UL fractions occupied 47.2% of the Yu, and each fraction was devided into nitrogen (ISF, AIF FF and LL) and non nitrogen (UL) groups. Effect of nitrogen fractions on the growth of rats was examined by addition of fractions to the casein diet. As the result, nitrogen balance and organ weights per body weight were as normal, but growth promoting effect was observed in either diet which each fraction was added to. Especially, the highest effect of non protein fraction, LL, in nitrogen fractions was suggested. Furthermore, effect of non nitrogen fraction, UL, on the growth of rats was examined in the same way. As the result, growth promoting effect equal to LL fraction was observed in the case of UL fraction.

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Gluconobacter oxydans OPE-107 has been identified as a bacterium causing the browning of canned pineapple. Pineapple fruit, pineapple juice and a glucose-peptone medium which were inoculated with the organism, developed a brown colour when they were heated. After 2 day-incubation with the organism, the glucose-peptone medium became acidic, and developed a brown colour with an absorption maximum at 440nm after heating. Our results suggest that the brown coloured material is comprised of thermal reaction products between certain amino acids and intermediates oxidatively produced from sugars by the organism. The most active amino acids were glycine, lysine and tryptophan, although other amino acids showed some activity. The precursor sugars were sucrose, glucose and fructose, which are major sugar constituents of pineapple.

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Structure of one of the water-soluble glycans from fruit body of Lyophyllum ulmarium was studied. An ethanol precipitate from a hot-water extracted fraction of the fruit body was treated with pronase and by the SEVAG method to remove protein. Then, polysaccharides, P-1, P-2 and P-3 were obtained by column chromatography using Sephacryl S-400 gel, and the structure of P-1 was examined. Homogeneity of each compound was confirmed by gel filtration, ultracentrifugal sedimentation analysis and electrophoresis. Molecular weight of P-1 was about 470000. A β-bond dominant structure was elucidated from the facts that [a]²⁰_Dwas+1.30 (C=1, water) and its infrared absorption spectrum. P-1 was composed of mannose, galactose and glucose in molar ratio of 1.0:1.9:5.1. To examine detailed bonding style, periodate oxidation, SMITH degradation and methylation analysis were conducted. Periodate consumption was 1.25mol and 0.56mol of formic acid was produced. Glycerol and non-oxidated glucitol were detected by SMITH degradation and their molar ratio was 1.8: 1.0. From the result of GLC and GLC-MS of the methylated sample, P-1 was estimated to possess a highly branched structure with 1-linked-D-glucopyranosyl+1-linked-D-manno-pyranosyl or one of these, 1, 3-linked-D -glucopyranosyl, 1, 6-linked-n-glucopyranosyl, 1, 6-linked-D-galactopyranosyl, 1, 3, 6-linked-D -glucbpyranosyl, 1, 2, 6-linked-D-galactopyra-nosyl residues. Partial hydrolysis with trifluoroacetic acid suggested that mannose, galactose and glucose were present at or near branch terminals, and the core of the molecule consisted mainly of glucose.

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In the previous paper we obtained three glycan fractions from an ethanol precipitate of a hot-water extracted fraction of Lyophyllum ulmarium by column chromatography using Sephacryl S-400 gel, a proposed possible structure of P-1. This paper describes chemical stuctures of P-2 and P-3. Molecular weights of P-2 and P-3 were about 108000 and 16000 respectively. [a]²⁰_D of P-2 and P-3 were +0.59 and+0.62 (C=1, water), and obvious absorption was detected at 890cm^-1 in their infrared spectra. From these reults, β-dominant bonding were elucidated for both compounds. P-2 was composed of mannose, galactose and glucose in the molar ratio of 1.0:2.3:1.4. And the component of P-3 was mannose and galactose (1.0:3.1). P-2 and p-3 consumed 1.22 and 1.68mol of periodate and produced 0.54 and 0.71mol of formic acid, respectively. SMITH degradation of P-2 provided glycerol and glucitol in the molar ratio of 2.5:1.0, but that of P-3 provided only glycerol. Methylation analysis suggested that P-2 had a branched structure with 1-linked-D-mannopyranosyl, 1, 3-linked-D-glucopyranosyl, 1, 6-1-inked-D-galactopyranosyl, 1, 3, 6-linked-D-glucopyranosyl and l, 2, 6-linked-D-galacte-pyranosyl residues, and P-3 had a highly branched structure with l-linked-D-mannopyranosyl, 1, 6-linked-D-galactopyranosyl, 1, 2, 6-linked-D-galactopy-ranosyl residues. By partial acid hydrolysis of P-2 mannose and galactose were obtained from the dialysate, indicating that a large amount of glucose was present in the core. Partial hydrolysis of P-3 suggested that mannose was presence at or near non-reducing terminals the core of the molecule consisted mainly of galactose.

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Storage of "Tenobe-somen" through a hot rainy season, which is called "Yaku", causes a desirable change in texture of cooked "somen". Total lipids were extracted from the "somen" before and after "Yaku" with water-saturated butanol and fractionated by silicic acid column chromatography into the three fractions of neutral lipids, glycolipids and phospholipids. Dry noodle samples were prepared from the flours consisting of defatted wheat flour and the total lipids before and after "Yaku". The effect of total lipids after "Yaku" on the texture of cooked noodle was similar to the texture change of "somen" caused by "Yaku". When reconstituted lipids wherein one of the three fractions before "Yaku" was replaced by the corresponding fraction after "Yaku" were added to noodle, only the neutral lipid replacement had effect similar to "Yaku" phenomenon. The chromatographic analyses of neutral lipid fractions on the column of Florisil deactivated with 7% water showed that the fraction after "Yaku" contained 3.5 times more free fatty acids and 17% less triglycerides than the same fraction before "Yaku". Some increases in monoglycerides and diglycerides were also observed. It was concluded that "Yaku" phenomenon of "somen" can be attributed mainly to fatty acids liberated by hydrolysis of triglycerides.

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The compositions of glycosides such as soybean saponins and isoflavones in various miso and effects of soybean saponins on sensory evaluation of miso were investigated. After extraction with 70% ethanol (v/v) from a lyophilized miso, the ethanol extract was partitioned between n-butanol and water (1:1; V/V). The upper layer (11 U) was regarded as the crude glycoside fraction of miso. The glycoside compositions and saponin contents in 11 U were examined by TLC and HPLC analyses. The TLC pattern of the crude glycoside fraction of soybean miso was different from those of rice and barley miso, and some specific components were detected. Daidzin and genistin in soybean miso were completely hydrolyzed into daidzein and genistein (their aglycones) while in sweet rice miso they were not hydrolyzed. The isoflavones in the semisweet rice, salty rice and barley miso were partially hydrolyzed. Soybean saponin A group having soyasapogenol A as an aglycone was partially deacetylated or hydrolyzed at the sugar moiety. The soybean saponin Bb contents of salty rice miso were in the range of 16 to 173mg% and the mean was 57mg% on a dry matter basis. Sensory evaluation of miso was designated as color, taste, flavor, texture and overall. In salty rice miso (n=202) the correlation coeffcientscients between the soybean saponin Bb content and sensory scores for color and flavor were 0.150 (P<0.05) and 0.205 (P<0.01), respectively. Therefore, the sensory evaluations for color and flavor showed a tendency to be lower with increasing the soybean saponin Bb content. Effects of removing seed coats of soybeans on sensory scores and the soybean saponin Bb content of salty rice miso were investigated. The soybean saponin Bb content was less in miso made from dehulled soybeans than in miso made from whole soybeans, and the sensory evaluations (color, taste, flavor, texture and overall) of miso made from dehulled soybeans miso were higher than those of miso made from whole soybeans.

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Sample solution containing various volatile compounds was aseptically filled into polyethylene terephthalate (PET) bottles with a volume of 300ml. The loss of volatile compounds due to sorption into PET bottle and the chemical changes of volatile compounds during storage were investigated by comparing with glass- and flexible pouch-packaged samples. (1) The distribution ratios (quantity of a compound recovered from PET bottle/quantity from sample solution) of volatile compounds after storage for 2 months were less than 0.7, thus the flavor deterioration due to sorption was not significant. (2) The aliphatic aldehydes were oxidized to carboxylic acids by dissolved oxygen during storage. On the other hand, the cyclic aldehydes were not oxidized. (3) The ethyl alkanoates were hydrolyzed to result in the production of carboxylic acids in PET or glass bottle. However, in pouch lined with middle-density polyethylene film, since the ethyl alkanoates sorbed into the liner predominantly, the extent of the hydrolysis was much smaller. (4) The interconversions of terpene alcohols led to the productions of 2, 6, 6-trimethyl-2-vinyl tetrahydropyran, terpin hydrate and α-terpineol in any type of container. The flavor deterioration in PET bottle during storage was not due to sorption of volatile compounds, but due to chemical changes of volatile compounds.

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Satsuma mandarin (Citrus unshiu Marc.) fruits were stored at 1°C, 8°C and 20°C, and dimethyl sulfide (DMS), an off-odor compound, accumulated in the central cavity was analyzed. At higher storage temperatures of 8°Cand 20°C, DMS concentration was getting higher during storage. Methionine-S-methylsulfonium (MMS), the precursor of DMS, in the juice also accumulated during storage at higher temperatures. Among 21 species of citrus fruits tested, the MMS content in juice and the DMS concentration in the central cavity were conspicuously higher in Satsuma mandarin. DMS formation by heating of Satsuma mandarin juice was determined in relation to occurrence of off-flavor by processing, and the production was found to be higher in juice taken from the fruit stored at higher temperatures.

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Emulsifying properties of plasma protein obtained from slaughtered pigs were compared with those of other animal proteins on the market (bovine plasma, egg white, egg yolk, whole egg, casein and whey). Plasma protein showed the highest emulsifying activity among the seven samples at pH 3 in the presence of NaCl and pH 7 in water. Emulsifying capacity of the plasma protein was the highest except the egg white. Emulsifying stability of the plasma protein after heating was the highest, however it was the lowest after freezing. This study proved that the plasma protein has agreat advantage to be utilized in food processing as a emulsifier. Since surface hydrophobicity and surface pressure of the plasma protein was lower than those of the egg yolk or the whole egg which have as high emulsifying properties as the plasma protein, it is suggested that surface hydrophobicity and surface pressure are not the important factors on emulsifying properties of the plasma protein.

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Ozone treatment on wheat flour was carried out with ozone-oxygen stream (0.05-50ppm ozone) at a flow rate of 100l/min at 10°C for 1-6h., and changes in rheological properties were investigated. Results obtained were asfollows; (1) In afarinograph test, there were no significant differences in the consistency of dough by thetreatment. With an extensograph, 0.50-50ppm ozone treatment of soft and medium flour increased resistance to extension, and 0.05-50ppm (soft flour), 5.0-50ppm (medium flour) ozone treatment decreased extensibility as compared to control. (2) Intramolecular SH groups of wheat flour were decreased about 30% by ozone treatment at 50ppm for 1 hour, but in termolecular S-S bond were increased about 5% by the same treatment. From the results obtained, it is suggested that changes in rheological properties of wheat flour were due to the oxidaitive effect of ozone same as other oxidative agents.

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The aroma concentrates of dorsal, abdomfinal and red meat parts of Katsuobushi were obtained by simultaneous distillation-extraction and then analyzed by gas chromatography and combined gas chromatography and mass spectrometry. Only a little difference in the aroma composition was observed between dorsal and abdominal parts. On the other hand, the amounts of the aroma compounds in the red meat part were larger than those in the dorsal and abdominal parts. Especially, alcohols, aldehydes and some furans, which have been known to be formed by oxidation of lipids, were larger in quantity in the red meat part.

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Thermal decomposition of added butylated hydroxyanisole (BHA) in oil and effects of gallic and thiodipropionic acids on decomposition of BHA were investigated. Oils (olive, coconut, soybean and corn oils) containing BHA, gallic acid and a mixtures of BHA and gallic acid were heated in a Pyrex glass tube (2.7cm×20.0cm) at 180°C using an oil bath. Residual BHA was determined by HPLC. The degree of thermal decomposition of BHA in oils was observed to be much higher in olive and coconut oils than in soybean and corn oils, and thermal decomposition of BHA in methyl esters of fatty acid was reduced in the order of stearate>oleate>linoleate. Thermal stability of BHA 2-isomer was higher than that of BHA 3-isomer. Decomposition of BHA in oil was apparently promoted by the addition of oxidation products (oxidized fatty acids: fatty acids insoluble in petroleum ether) of oil. But the addition of gallic and thiodipropionic acids suppressed the thermal decomposition of BHA by oxidized fatty acids.

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The inhibitory effects of mustard and its major pungent compound, allyl isothiocyanate (AIT) on the growth of five species of bacteria and the relation between their inhibitory activities were studied. Brown mustard extract was prepared as 20% mustard in 70% ethanol after myrosinase treatment. AIT was dissolved in 70% ethanol to form a concentration equivalent to that in the mustard extract. Bacteria were cultured in nutrient broth containing the mustard extract or AIT at 30°C on a reciprocal shaker, and bacterial growth was determined by turbidimetry. The duration of the lag phase of growth was proportional to the concentration of mustard or AIT in the medium, and the turbidity of the stationary phase was sometimes decreased by these inhibitors. The concentrations of mustard in the medium that inhibited bacterial growth for 24h were 0.138%, 0.104%, 0.064%, 0.043% and 0.089%, and those of AIT were 14.5, 12.3, 6.5, 3.6 and 7.2ppm for Staphylococcus aureus, Escherichia coli, Proteus vulgaris, Pseudomonas fragi and Ps. aeruginosa, respectively. These results suggested that the inhibitory effect of mustard was mainly due to AIT. Furthermore, it was recognized that the effect of mustard on S. aureus and E. coli was bacteriostatic at 0.8% whereas that on Ps. aeruginosa was bactericidal at 0.2%.

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