Globin was heated in various concentrations of urea solution and the emulsifying properties (Emulsifying activity and Emulsion stability) of the resulting globin were investigated. Emulsifying properties of the globin varied greatly with urea concentration examined. As a result, when globin was treated with 6M urea, it showed several outstanding emulsifying properties. For example, 1) Though the emulsifying properties of globin became worst at pH 7.0, UHG (Globin treated with 6M urea) provided emulsifying properties superior to those of globin at the same pH. 2) The proteins adsorbed on the surface of fat globules of UHG emulsion amounted to 5.25 times that of the globules of globin emulsion at pH 7.0. 3) Surface hydrophobicity of UHG decreased markedly at pH 7.0 as compared with that of globin. The complexes of UHG with fatty acids were prepared, and then the emulsifying properties of these substances were studied. As a consequence, the emulsifying pro-perties of these substances were not comparable to that of UHG.

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Two kinds of fresh Satsuma mandarin juices prepared by either FMC TM In-line extractor or chopper pulper extrator, and a reconstituted Satsuma mandarin juice prepared by the In-line extractor, were clarified by using ultrafiltration (UF) units equipped with either a polysulfone membrane (molecular weight cut-off of 50, 000 daltons) or two kinds of inorganic (zirconia) membranes (molecular weight cut-off of 20, 000 and 50, 000 daltons. respectively). In order to increase the permeation rate, it was necessary to centrifuge prepared juices prior to UF treatment. In UF treatments, the higher flux was obtained in fresh juice prepared by the In-line extractor. There was no difference between juices clarified by UF treatment in chemical components except for color and flavor of investigated juices. The juice clarified by ultrafiltration gave light color in juices clarified by inorganic membranes and the flavor was favorable in clarified fresh Satsuma mandarin juices prepared by the In-line extractor.

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The microbial count is an index of suitability of raw milk handling, and also one of the most essential items to judge milk quality. The measurement of the microbial count is usually carried out by direct counting with a microscope or by colony counting on an agar plate. However, these methods involve complicated procedures and need special techniques. In order to overcome these drawbacks, a convenient and rapid estimation method for the microbial count in raw milks was developed based on a colorimetric reaction using vitamin K₃ and nitro blue tetrazolium (NBT) available as a substrate of the electron transport system of microorganism. NBT was dissolved at a concentration of 1mM in 0.2M potassium phosphate buffer (pH 7.0) saturated with vitamin K₃ followed by mixing with an equivalent volume of a raw milk for 20 or 40min. The change of b value determined with a colorimeter during the reaction was linearly related to the microbial counting by the agar plate method on a log-log plot (n=41, r=0.942). The lower detection limit of the microbial count by the present method was about 1×10⁵/ml. Reducing substances such as uric acid, ascorbic acid and lactose did not interfere with the color reaction at the usual level in raw milk. As the color change by the present method can be easily recognized with the naked eye without a special colorimeter, the method would be practically applicable not only in the laboratory but also in field work.

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Effects of monoglyceride on breadmaking properties were investigated by employing three types of monoglycerides: glyceryl monostearate (GMS) as saturated monoglyceride, glyceryl monooleate (GMO) as cis-unsaturated monoglyceride and glyceryl monoelaidate (GME) as trans-unsaturated monoglyceride. Polymorphism of monoglycerides, which was considered as a factor of their dispersibility in an aqueous solution, was first examined by using X-ray diffraction and DSC analysis. In GMS and GMO, stable crystal state remained during storage at 20°C, and in GME unstable crystal state was easily transformed to stable one. The unstable crystal of GME was considered to improve its dispersibility in dough as well as in the aqueous solution. The characteristics of dough with or without addition of these monoglycerides were investigated by Farinograph and Extensigraph. Breadmaking were tested according to 70% sponge-dough procedure method. Each monoglyceride was added in dough less than 1% on flour weight basis. The dough consistency decreased definitely during mixing, and the dough strength to extension increased by the addition of GMO or GME. The loaf volume increased by the addition of GMO or GME. These effects were not shown by the addition of GMS. The change in crumb firmness during storage was depressed by the addition of GMS or GME, providing a softer bread. In order to elucidate a mechanism of dough improvement, the added monoglycerides were extracted from dough much more. GMO and GME were located in the gluten fraction than GMS. It suggested that the double bonds of unsaturated monoglycerides were bound easily to the gluten fraction, so that the amount of monoglycerides in the gluten fraction influenced the dough characteristics.

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The effects of radiative characteristics of heaters on crust formation and coloring process of white bread have been studied. Five heaters of different kinds were used at a constant electric power, however, experimental results showed that the radiative heat fluxes from the heaters were different each other. The heaters emitting the shorter wave length have the larger radiative heat flux. The maximum difference of the radiative heat fluxes between the five heaters is about 24%. The evaporation rate of water from the bread and the thickness of the crust layer depend more on the radiative heat flux than the radiative characteristic. Especially, for the heaters which have the peak emission wave length in the near-infrared region, the contribution of the radiative heat flux on the crust layer thickness is very high. The water content of the crust layer is affected firstly by the radiative heat flux, then this influence becomes weaker with time, and finally it depends on the radiative characteristics of heaters. The coloring process is strongly affected by the radiative characteristics when the heaters emitting the far-infrared wave are used. On the other hand, for the heaters emitting the near-infrared wave, the radiative heat flux affects more on the coloring process.

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Antioxidative activity of extracts from buckwheat seeds was examined by measuring the inhibition of 2, 2'-Azobis (2, 4-dimethylvaleronitrile) (AMVN)-initiated peroxidation of methyl linoleate in a solution composed of n-hexane, 2-propanol, and ethanol (8: 3: 1, v/v/v). The rate of lipid peroxidation (R_inh/R_p×100, %) was determined in the presence of each extract from pericarps and grains using petroleum ether, ethyl acetate, and 99.5% ethanol. Inhibitory activity of lipid peroxidation, that is, antioxidative activity was the highest for the ethanol extracts among these extracts. There was no significant change in the activity of the ethanol extracts during at least a month after extraction under storing at -20°C. Therefore, in order to evaluate breeding materials of buckwheat with respect to antioxidative activity, ethanol extracts from seeds were submitted to the measurement within a month after extraction. Antioxidative activity of ethanol extracts from pericarps and from grains of ten varieties of buckwheat harvested at 1985 was varied substantially. The peroxy radical-scavenging activity (k_inh/k_p) was ranging from 83 to 124 in ethanol extracts from pericarps, and from 97 to 118 in those from grains. K_inh/k_p values of antioxidants compared with buckwheat extracts were as follows: alpha-tocopherol, 10 to 20 times high; quercetin, 2 times high; caffeic acid, almost the same; ferulic acid, 2 times small. Since it is complicated and time-consuming to measure the rate of lipid peroxidation in a solution, we attempted to estimate the rate in the presence of ethanol extracts from buckwheat seeds rapidly from the total polyphenol content in the extracts. The rate decreased linearly with increasing of log e of the polyphenol content in ethanol extracts both from pericarps and grains. Consequently, we could estimate the rate by measuring the total polyphenol content in ethanol extracts with 2.8% of the standard error in pericarps and 4.1% in grains. These results indicate that we can evaluate the antioxidative activity of breeding materials of buckwheat based on their polyphenol content.

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The effects of exposure of concentrated carbon dioxide, i.e., 6000ppm was investigated on the weight; water, protein, lipid, carbohydrate and ash as major constituents; Ca, Fe, Na, K and Zn as minerals; thiamin, riboflavin and ascorbic acid as vitamins; and fatty acid composition on dry matter basis of whole fruit body during the cultivation of Bunashimeji mushroom: Hypsizigus marmoreus (Peck) Bigelow. A significant increase of the weight was observed in 0 days (slightly) and 5 days (1.4 times) after CO₂ exposure (the harvest time). The increase was observed in major constituents except carbohydrate, all minerals, riboflavin, linoleic acid contents and olyunsaturated fatty acid/saturated fatty acid ratio in the whole on the 0 days after CO₂ exposure. On the other hand, an increase was observed in major constituents except carbohydrate, minerals except Na and Zn, riboflavin, ascorbic acid, stearic acid, linoleic acid contents and polyunsaturated fatty acid/saturated fatty acid ratio in the whole on the harvest time.

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Cucumber (Cucumins sativus LINN.) was treated with sodium hypochlorite (NaOCl) under various conditions (pH4-10, effective chlorine 25-200ppm, and 10-40°C). The effect of NaOCl on microorganisms of cucumber increased by adjulsting the pH to 4-6. The effect increased according the concentration of available chlorine up to 100ppm. No remarkable effect was observed above 100ppm. As the effect was greater under high temperature, the time was shortened under high temperature. By the optimum condition (100ppm, pH 6.0, 20°C, 30min), the microbial numbers of cucumber could be reduced to a hundredth of the initial (10⁵-10⁶/g).

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The complexes of globin with fatty acids were prepared after pre-treatment of globin with several chemicals. Stearic acid, myristic acid and decanoic acid were used as fatty acids. The emulsifying properties of the resulting complexes or the pretreated globin were then investigated. When globin was pretreated with ethyl alcohol, urea, heated urea or β-ercaptoethanol, the affinity of the globin for fatty acids altered. As a consequence, the emulsifying properties of each globin also changed markedly. For example, globin emulsion was unstable at pH 7.0. However, the emulsion of globin pretreated with heated urea or β-mercaptoethanol was rather stable at the same pH. The emulsifying properties of globin were improved by formation of globin-fatty acid complex. In particular, the complexes of fatty acids and globin pretreated with heated urea had emulsifying properties superior to the other complexes.

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An aptitude of soy protein gel for gel-type food, sausage, hamburg and satsuma-age was investigated. The cold-gel has high aptitude for gel-type food as compared with heat-gel, freeze-gel and SPI. The cold-gel had high ability of substitution for meat or fish paste. Especially, good result was obtained in food that had heterogeneous texture like hamburg. Based on the results both texturometer measurement and sensory evaluation, the hamburg replaced 50% of animal meat by cold-gel was nearly equal on texture as compared with control. On the other hand, heat-gel and freeze-gel decreased elasticity. As mentioned above, characteristics of cold-gel has maintained quality of the final food. It was assumed that gelation of cold-gel owed to large contribution of hydrophobic and hydrogen bond, as compared with heat-gel and freeze-gel. The difference of mechanism of gelation was considered to have improved affinity with animal meat and fish paste in the final food.

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A diffused odor of fish oil derived in oxidation was measured by an odor sensor. A slight odor of initial stage in oxidation could be accurately measured. The induction period could be also judged by this method. It was shown that the odor concentration value was closely correlated with the peroxide value. This method was a simple and rapid to determine oxidative rancidity of fish oil, and would be useful for a management of quality of oil and estimation of rancidity.

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Pleurotus ostreatus and Pholiota nameko were cultivated in calcium added media. We traced the changes of the course of stages of mycelial growth of these mushroom in PSA and sawdust media which added the calcium compounds in concentrations of 1, 5 and 10%. The calcium content in the fruit-bodies of these mushrooms after harvesting was determined. The results were as follows: (1) Both mycelial growth and absorption of calcium for these mushroom were affected by the amounts added, the initial pH value of the medium and the type of compound used. (2) When compared among the calcium phosphate, sulfate, carbonate and acetate, the calcium carbonate showed the best mycelial growth for P. ostreatus in the PSA and the sawdust media. The amount of calcium in fruit-bodies in sawdust medium increased about 1.4 times, as compared with that in an untreated culture medium. (3) Calcium phosphate was most effective for promoting P. nameko mycelial growth in a PSA and sawdust medium. The amount of calcium in fruit-bodies cultivated in a sawdust medium was 2.3 times greater than that cultivated in an untreated culture medium.

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The effect of essential oils on permeation flux of ultrafiltration (UF) membranes were studied by using a model Satsuma mandarin juice. The UF units equipped with a polysulfone membrane (molecular weight cut-off of 50000 daltons) and inorganic (zirconia) membranes (molecular weight cut-off of 50000 daltons) were used. Using the polysulfone membrane, a permeation flux decreased due to adsorption of essential oils to the membrane surface. While essential oils had little effect on a permeation flux in the presence of pectin. Using the inorganic membranes, essential oils had no effect on a permeation flux. The permeate through the polysulfone membrane contained monoterpene hydrocarbons in trace amounts and the permeate from the inorganic membrane contained them in extremely small quantities. On the other hand, linalool, one of terpene alcohols, well permeated through the all membranes.

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The cell wall polysaccharides in fresh and brined ume fruits were fractionated, and the relation between their chemical composition and hardness was investigated. The main components of each cell wall polysaccharide were as follows: pectin fraction (PS) containing galacturonic acid (AGA), hemicellulose I fraction (HC-I) containing neutral sugars and proteins, hemicellulose II (HC-II) containing neutral sugars and ash, and cellulose fraction (CL) containing neutral sugars. In the Control (ume fruit brined with NaCl solution), there was a decrease in HC-I and CL in the cell Wall. and an increase in PS, as well as a softening of texture. On the other hand, a decrease of PS and an increase of CL Were observed in the Ca-added group (ume fruit brined with NaCl solution and Ca hydroxide), which maintained a hard texture. A decrease in the methoxyl group and an increase in ash and Ca content were observed in PS of the Ca-added group. A decrease of neultral sugar (especially, glucose composition) and an increase in ash, Ca and AGA content were observed in CL. CL contained AGA and neutral sugars such as arabinose and galactose, which were thought to be firmly bound to cellulose microfibrils. Therefore, it was assumed that the hardness in Umezuke may reflect a difference in the mechanism of bonding between CL existing in the Secondary cell Wall and other matrix polysaccharides.

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The adsorption of high methoxyl (HM) and low methoxyl (LM) pectins onto stainless steel surfaces was studied in an investigation of the fouling mechanism using nonporous stainless steel particles. The negative charge equivalents of the HM and LM pectins increased with increasing pH, and was accompanied by the charge-induced molecular expansion. HM and LM pectins could be spontaneously adsorbed on both positively and negatively charged stainless steel surfaces in a pH range of 3 to 6. The adsorption isotherms of the HM and LM pectins were similar to Langmuir-type ones. The saturation amounts of HM and LM adsorbed pectins increased with decreasing pH values and were correlated with the degree of dissociation of the carboxyl groups in the pectin molecules. While the undissociated HM and LM pectins adsorbed on stainless steel surfaces were easily released into the aqueous phase by alkali cleaning, anionic HM and LM pectins bound to positively charged stainless steel surfaces showed a high resistance to alkali cleaning. In a pH range where the HM and LM pectins and stainless steel surfaces were oppositely charged, shielding of the charges and intermolecular cross-linkage of the HM and LM pectins by monovalent or divalent cations also resulted in large amounts of pectins adsorbed and in the good release of the adsorbed pectin molecules during the alkali cleaning. It is concluded that the adsorption and desorption behavior of the pectins at the stainless steel-solution interfaces was largely determined by the electrical states of the pectin molecules and stainless steel surfaces.

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Changes in levels of chlorophyll (Chl) and its derivative and Chl degrading enzyme activity were examined to elucidate the pathway of Chl degradation in stored mitsuba (Japanese hornwort, Cryptotaenia japonica Hassk. cv Senkaku) leaves. Chl content decreased markedly concurrent with the yellowing of leaves. Chlorophyllide (Chlide) a and 13²-hydroxychlorophyll a eluted as a Chl derivative, but their levels were low and did not increase during storage at 25°C. Chlorophyllase activity increased significantly with the yellowing of leaves. In contrast with its activity, peroxidase activity decreased markedly with the senescence of leaves. Additionally, lipoxygenase activity increased during storage at 1°C and 25°C. The activities of enzymes relating to Chl degradation, such as chlorophyllase, peroxidase, lipoxygenase and Chl oxidase, Were found in the chloroplasts of mitsuba leaves. These results suggest that Chl is degraded by chlorophyllase to Chlide and then the oxidative degradation of Chlide to a colorless compound occurs inside chloroplasts of mitsuba leaves.

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Some characteristics of the milkfish sarcoplasmic protein (Sp-P) recovered from the wash water of surimi production using an ultrafiltration unit were investigated. Based on heating from 25 to 90°C at a rate of 1°C/min, thermally induced aggregation and an obvious turbidity change occurred at the temperatures above 40°C. Heat coagulability did not change up to 50°C. The reactive SH group gradually increased with by heating and reached the highest value at 50°C. The emulsifying activity was improved with an increase in the Sp-P Concentration but the activity was lost when heated above 40°C. From the DSC thermogram, the denaturation of the recovered Sp-P was observed at the temperature range of 40 to 50°C.

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