Harusame noodles were prepared with an extruder from starches of mung beans and broad beans obtained by alkaline or fermentation method. The physico-chemical properties of these Harusame noodles were determined and results were compared with those of commercial products.
The physical properties, such as opacity against scattered light and tensile strength and resistance to elongation, were measured with noodles prepared from starch of fermentation method. All of these values were higher than those obtained with noodles prepared from starch of alkaline method. These results suggest that alkaline method is preferable to fermentation method for making Harusame.
Even though broad beans and mung beans starches have almost the same amylose content, the physico-chemical properties of Harusame noodles of broad beans were inferior to those of mung beans. As this inferior properties would be due to the difference of the chain length distribution of amylopectin molecule, this distribution was checked from the gel column chromatogram of polysaccharides obtained by the hydrolysis of these starches by Pseudomonas isoamylase. As the result, the presence of the relationship between the structure of starch and the physico-chemical properties of noodles was somewhat revealed.
We found that the origins of starch and the production method of the noodle strongly affected the quality of the Harusame noodles.

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The mixture of potato starch and corn starch was added in a Codfish meat paste, and traditional Japanese food Kamaboko was prepared. Then the physical properties of Kamaboko were studied, and the following results were obtained.
1) The gel-strength of Kamaboko containing mixed starches increased higher than the controls, when 10-20% of corn starch was admixed with potato starch.
2) The change of the gel strength of Kamaboko during preservation under low temperature after heating up to 75, 85, and 95°C, was similar to that of potato starch gel.
The physical properties of potato starch-wheat starch mixed gels were studied. The starch mixture was added to pork meat, and the Chopped hams were prepared. Then the physical properties of ham were studied, and the following results were obtained.
1) The gel strength of the mixed starch gels increased slightly with increase of potato starch content, while the separated water increased sigmoidally after heating up to 70-80°C.
2) The change of the gel strength and the separated water of Chopped ham was similar to those of starch gels.

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An α-glucosidase has been isolated from Bacillus cereus NY-14 in electrophoretically homogeneous form, and its properties have been investigated. The purified enzyme had a molecular weight of 57, 000, an isoelectric point of 5.74, an optimum pH of 7.0, and an optimum temperature of 24°C. This enzyme was stable below 20°C and the pH-stability range was relatively narrow. The enzyme retained more than 90% of its initial activity in the range of pH 6.0 to 7.0. The purified enzyme hydrolyzed maltose, maltotriose, maltotetraose and isopanose, but showed no activity on polysaccharides, such as amylose, amylopectin, glycogen and soluble starch. The K_m value for maltose was 4.94mM. On the basis of inhibition studies with p-chloromercuribenzoate, it was assumed that this enzyme contained sulfhydryl residue essential for its catalytic activity.

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An α-glucosidase has been isolated from Bacillus cereus NY-14 in electrophoretically homogeneous form, and its properties have been investigated. The purified enzyme had a molecular weight of 61, 000, an isoelectric point of 5.05, an optimum pH of 6.5, and an optimum temperature of 21°C. This enzyme was stable below 25°C and pH-stability range was relatively narrow, the enzyme retained more than 70% of its initial activity in the range of pH 6.9 to 7.9. The purified enzyme hydrolyzed isomaltose, isomaltotriose, panose, p-nitrophenyl α-D-glucopyranoside and turanose, but showed no activity on maltooligosaccharides and polysaccharides, such as amylose, amylopectin, glycogen, pullulan and soluble starch. The K_m values for isomaltose, isomaltotriose and panose were 5.32mM, 2.10mM and 2.64mM, respectively. The enzyme was activated by Ba²⁺, Ca²⁺ and EDTA, but inhibited by p-chloromercuribenzoate. On this basis, it was assumed that this enzyme contained sulfhydryl residue essential for its catalytic activity.

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Starch samples were prepared from the three kinds of tubers of Musa (Musaceae): Banana, Musa paradisiaca Linn. var. sapientum O. Kuntze; Basho, Musa basjoo Sieb. et Zucc.; and Hime-basho, Musa coccinea Andr., with dilute aqueous alkali solution in the yields of 5, 4 and 5% of the fresh tissues, respectively.
These starches were examined on granular size and shape, contents of phosphorus and protein, X-ray diffraction pattern, iodine coloration, swelling power, solubility, amylogram, digestibility of raw starches by glucoamylase and other properties.
Both starches of Banana and Basho resembled each other in all properties estimated. They had the shape of thin-flat disks with a large diameter, 35μm on the average, and were hard to be digested by glucoamylase. In addition, they showed extremely low solubilities as compared with swelling powers, and higher viscosities in amylograms. On the other hand, Hime-basho starch had the elongated shape having an average dimension of 6×33μm, and its high resistance to glucoamylase and other properties were similar to those of the former two but its gelatinizing property was resemble to that of sweet potato starch.

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Starch samples were prepared from the roots of Gishigishi, Rumex japonicus Houtt. (Polygonaceae); Suiba, Rumex acetosa Linn. (Polygonaceae); Udo, Aralia cordata Thunb. (Araliaceae); and rhizome of Sokuzu, Sambucus chinensis Lindl. (Caprifoliaceae) in the yields of 7, 6, 5 and 8% of the fresh tissues, respectively.
These starches were examined on granular size and shape, contents of phosphorus and protein, X-ray diffraction pattern, iodine coloration, swelling power, solubility, amylogram, digestibility of raw starches by glucoamylase and other properties.
It was found that both of the starches of Gishigishi and Suiba not only resembled in that they assumed reddish color in the course of purification but also had similar poperties in all respects except that they were different in granular shape. Udo starch had a high swelling power and its viscosity curve rose at very low temperature (58°) on amylogram. The granular size of Sokuzu starch was very small, 1μm or less, but it showed higher resistance against glucoamylase. In addition, Sokuzu starch had the highest swelling power among 5 starches tested and showed a peculiar property such as lower solubility at higher temperature. It is assumed that these physical properties are due to its high phosphorus content (0.095%).

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In the reaction of cyclodextrin glucanotransferase (CGT-ase) on liquefied starch, the producing ratio of α-CD, β-CD, and γ-CD is different from origins of CGT-ase. For example, CGT-ase obtained from Bacillus megaterium and Bacillus species (alkalophilic) produces β-CD as the major product, while CGT-ase obtained from Bacillus macerans produces α-CD predominantly. At earlier stage of reaction, B. macerans CGT-ase produces mainly α-CD but according with the prolonged reaction time, the quantity of α-CD once produced will decrease, on the contrary the β-CD's quantity will increase. So the preparation of β-CD is relatively easier than that of α-CD, because of all CGT-ase synthesizes mainly β-CD.
α-CD is preferable for the food processing and for other various applications due to its higher solubility; β-CD has the poor solubility in water. We have been starting to establish the industrial production of the CD's mixture product which contains high α-CD at low cost. This study is based on the several researches done by Kobayashi and Kainuma of National Food Research Institute.
In this paper, we report on the suitable conditions of liquefaction of starch using CGT-ase and we also report that the activity of CGT-ase in the cyclization reaction becomes higher and more stable in the thin substrate concentration.

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In our previous study of this series, we reported that the yield of cyclodextrins depends upon the concentrations of liquefied starch solution. In concentration below 5%, the conversion of potato starch to cyclodextrins by CGT-ase (cyclodextrin glucanotransferase) is highly promoted.
In this report, the concentration method of very diluted cyclodextrins mixture solution by using the reverse osmosis membrane is reported. It was cleared that the spiral wound type membrane module of synthetic high polymer has a efficient capacity for concentration of CGT-ase's conversion mixture.

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The yield of cyclodextrins from starch will depend on the microbial origin of the enzyme and other reaction conditions, and in general it is difficult to get CD yield higher than 50%. To increase the cyclodextrins content in the reaction mixture, the separation of cyclodextrins and linear dextrins is necessary step.
In this study, the separation of cyclodextrins from linear dextrins using the dynamic membrane method is reported. As a dynamic module tube, porous ceramics tubes subjected to coat with alumina on the tube's surface layer was used. The dynamic membrane was formed by circulating the mixture solution itself which must be separated under pressure through the module tube. Then linear dextrins of larger molecular weight were caught at the surface of ceramics tubes, larger linear dextrins deposited on the surface layer after expiration of a fixed time, and a membrane was formed. This membrane rejected linear dextrins by themselves.
As the result, cyclodextrins content of 76.3% in total permeate was obtained under operation pressure of 5-20 kg/cm². Results suggest the feasibility of using the dynamic membrane method for the separation of cyclodextrins and linear dextrins in the industrial process.

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