Inclusion of air into dough during mixing and deaeration from dough during rest or sheeting were investigated by measuring the density of dough. The density of doughdecreased with an increase of mixing time when using a mixer. The smaller the water content or the larger the amount of NaCl, the less the decreasing rate of dough density.Neither addition of NEMI nor cysteine did not change the dough density. While, by hand mixing, the density was almost constant through mixing.The density increased during restperiod and the increase was remarkable especially within 2h of rest. The increasincrease of density in the rest periodwas great for the dough which showed a larger density duringmixing. From these results, it was considered that inclusion of air into dough cause thedecrease of dough density by mixing and deaeration from dough cause the increase of doughdensity by rest. While, sheeting of dough did not show a variation of density, so itsuggested that sheeting did not cause deaeration. The relaxation modulus of the cookednoodle prepared from the dough which had been rested for 4h was 1.4 fold as large as that ofthe sample prepared from the unrested dough. Reason for this increase of relaxationmodulus is considered to be due to compacting of dough structure by deaeration from dough.

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Changes in apparent physical properties of pastes of glutinous and non-glutinous rice flours caused by heating and additives were analysed by the parameters in the multi-biting test. Parameters of the apparent springiness characteristics of the pastes of both rice flours obtained by the multi-biting were greatly increased or decreased by the addition of sodium parmitate, phosphoric acid or NaCl when they were compared to the normal pastes of rice flours heated at 98°C. But these changes were greatly different between the pastes of glutinous and non-glutinous rice flours under other heating conditions especialy at 80°C and lower. These apparent physical changes of the pastes of both rice flours due to the heating conditions and the additives could also be analysed by the ratio of the parameter of apparent viscosity characteristics vs the parameter of apparent springiness characteristics obtained by the multi-biting test. These changes in the apparent physical properties of the pastes of both rice flours would be correlated not only to the additives but also to the gelatinization characters of the starch pastes of both rice flours.

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Pasting properties of corn and waxy corn starches in different heating conditions were analyzed by using the multi-biting test. Changes in the physical properties of corn and waxy corn starches in different heating conditions could be analyzed effectively by theparameters obtained from the multi-biting test. Pasting properties of corn and waxy cornstarches were much different depending upon the heating conditions and the kind of these starches. Addition of NaCl restrained gelatinization and gelation of the starch pastes prepared from corn and waxy corn starches, while their viscoelasticities were much influenced by the heating conditions. Effects of the addition of sodium palmitate and phosphoric acid to the pastes of starches were also much different according to the heating conditions and the kind of these starches. It was estimated that the rheological changes caused by the addition of the additives to the pastes of both starches in different heating conditions would be complicated in connection not only with additives but also with the gelatinization and gelation characteristics of both starches.

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The effects of pH and desalting on the elimination of β-lactoglobulin (β-LG) from bovine whey by using carboxymethyl cellulose (CMC) cation exchanger were investigated. Desalting of whey enhanced the amount of adsorbed β-LG on CMC cation exchanger. However, excess desalting, i. e. more than 90% as conductivity, reduced the selective adsorption of β-LG to CMC cation exchanger. Selective adsorption of β-LG on CMC cation exchanger conld be performed at pH 4.6 in the case of using the whey which was dialysed for 48h. If the pH of whey was lower than 4.0, not only β-LG but also other proteins, for example, α-lactalbumin (a-LA), bovine serum albumin (BSA) and immunoglobulin (lgs), were adsorbed on CMC cation exchanger. On the other hand, if the pH was higher than 5.0, major whey proteins containing β-LG could not be adsorbed on CMC cation exchanger. We could obtain two types of freeze-dried whey protein fractions. One is β-LG eliminated whey powder which showed good solubility and heat stability, and the other is β-LG rich whey protein isolate.β-LG accounted for less than 20% of major proteins in the β-LG eliminated fraction, while more than 90% of major proteins in the β-LG rich fraction.

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Changes in the components and sensory quality of frozen pods of green soybean (Glycine max L. cv. Tamasudare) were examined to elucidate a suitable holding period after harvest before processing. The pods, harvested 30 days after flowering (DAF), were held for different periods at 26°C and 64-68% RH, then blanched and frozen in liquid N2 and stored at -20°C. After 3 months, the pods were cooked in boiling water, and the seeds, edible parts, were used to analysis. Sucrose levels decreased from 2.9% (fresh weight basis) to 1.6 and 1.0% during 24 and 48h, respectively. Galactopinitols decreased during holding period. Contents of total free amino acids, alanine and glutamic acid decreased from 1.2, 0.3 and 0.2% to 0.9, 0.2 and 0.1% during 24h, respectively. Starch and protein contents were 6.8 and 27.5% (dry weight basis) and the former increased during holding period. The cooked pods, frozen for 2 weeks, were evaluated for sensory quality: sweetness, taste and texture of seeds; aroma and overall quality of whole pods. Their scores declined with elongation of the holding period, but no differences were found in the scores between 30min-and 8h-pods. The 24h-pods were significantly inferior to 8h-ones in sensory quality except texture. The declines in sensory scores sweetness and taste during holding period coincided with the decreases in sucrose, glutamic acid and alanine contents. Consequently, green soybean pods held at room temperature should be blanched and frozen within 8h. Effect of delay of harvesting time on the quality was also examined . Seeds of 32 DAF seeds contained more sugars and free amino acids, but had not so good aroma as those of 30 DAF.

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Glucosamine in free-form was browned in powder, inaqueous solution and as anhydride. Brownish products were fractionated with methanol and ethanol and their properties were determined. The products were also fractionated by thin-layer chromatography (TLG). Type G product which was heated lh at 90°C showed the highest antioxidative activity. Among the methanol and ethanol fractions, in solubleones showed the highest antioxidative activity. The activity of each fraction fractionated with TLC was lower than those of unfractionaeted.

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In order to improve the texture of cucumber pickles, the effect of addition of natural polysaccharides (low methoxyl and high methoxyl pectin, pullulan, chitosan) on firmness, instead of adding CaCl² generally used, was studied by analyzing the characteristic properties of pectin components of cucumber pickles. 1. The effect of low methoxyl and high methoxyl pectin, and pullulan on texture improvement of cucumber pickles was not found. 2. On chitosan treatment, the firmness of cucumber pickles definitely increased as the amount of chitosan increased. 3. With increasing the added amount of chitosan, hexametaphosphate soluble pectin (PSP) decreased, While hydrochloric acid soluble pectin (HSP) and sodium hydroxide soluble pectin (SSP) increased. Firmness was Found to increase in proportion to the increase of the ratio of HSP and SSP in total pectin.

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Astringency of Japanese persimmon'Saijyo' was removed by CO2 treatment. Pressure decrease in a hermetic vessel containing the fruits adsorbed CO2, the CO2 content in the fruits and the desorption rate out of them were measured. The manometer connected with a hermetic vessel containing persimmon fruits indicated pressure drop immediately after the introduction of CO2 at 23°C and the maximum value of the reduced pressure was held between 2 and 6h. The pressure in the vessel returned to the initial pressure between 13 and 14h and after that a little increase of the pressure was observed. Japanese persimmon'Saijyo' fruits adsorbed considerable amount of CO2 after its introduction in order to remove astringency. The carbon dioxide content per 100g of the fruits was about 7ml in the untreated ones and 55 to 60ml in the ones at 3rd day after CO2 treatment. The released CO2 volume out of the fruits decreased with the advancement of maturity and development of the surface color of the fruits. The CO2 volume released from the fruits at 2nd day after picking was about a half of that from the fruits immediately after picking, regardless of maturity. The more the CO2 concentration during de-astringent treatment, the more the amount of CO2 released From the persimmon fruits after de-astringent treatment. The releasing rate of CO2 was very rapid for l h after the hermetic vessel was opened and then became slow. The rate was about 5 times the values of untreated fruits even 6 h after opening the vessel.

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A determination method of butylated hydroxytoluene (BHT) and butylated hydroxyanisole (BHA) in dried fish, salad oil, and butter by gas chromatography (GC) with wide bore column was investigated. BHT and BHA were extracted from foods by essential oil distillator, and analysed by GC. Three wide bore columns bonded chemically on fused silica, i.e. CBP1 (corresponds to SE-30), DB 17 (OV-17) and CBP 20(PEG-20M) were used. The size of 3 columns was O.53mmi.d.x12m or15m length and the coating thickness was 1.0um. Three columns were utilizable for the analysis of BHT and BHA insalad oil. CBP l and CBP 20 were effective for dried fish and CBP l was effective for butter, respectively. Recoveries of BHT and BHA added to foods at 50 ppm levels were in the range of 81.1 to 94.3%. The retention time of BHT, BHA, fluorene as an internal standard and paraffinic hydrocarbons were measured by GC with each column. The analysis of BHT was interfered with n-pentadecane in CBP l column, and n-heptadecane and pristane in DB 17 column. The retention time of fluorene was same as that of n-tricosane in CBP 20 column.

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