In order to improve the boiling process of raw noodle, to increase the yield of product, and to reduce BOD load in waste water from the noodle factory, experiments were performed on the material loss during boiling raw noodle in hot water, in relation to the previous work of the processing conditions reported in Part I. The chemical composition of solid substance in the boiling water was also analized. The following results were obtained:
1) Material loss increased rapidly in several minutes after begining of boiling, and increased in proportion to the boiling time.
2) In cooking, material loss was minimum at 98.5°C and increased slightly at the other temperature.
3) The repeating use of boiling water caused increase of the concentration of dissolved matter and decrease of the material loss. Close correlation between the concentration of dissolved matter in boiling water and the material loss was confirmed.
4) Increase of the qantity of raw noodle in a batch process at boiling gave a slight decrease of material loss.
5) The solid substance of the boiling water consist with more than 50% starch and the quantity increased as increasing the boiling time. The quanity of low molecular substance such as salt and reducing sugar was detected at the early stage.
6) By the examination of waste water from small-scale noodle factories having different boiling equipment as well as various condition of boiling, much differences were found in the concentration and composition of solid matter.

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The pH value of fresh apple pulp was adjusted from 3.0 to 3.8, 4.4 and 5.0 by addition of ammonia to increase activity and stability of malic enzyme of apple fruit during "maceration" treatment in cider-making. Decrease in malic acid content of the juice during maceration became appreciably larger by neutralization of the pulp; especially pH values above 4 caused remarkable decrease. Besides, pectin and tannin contents of the juice decreased more largely; amounts of lactic and succinic acid in the juice slightly increased; and yield of the pressed juice slightly increased, by high-pH-maceration. Alcholic fermentation of the juice obtained was rapid and ethanol content of the resulted cider was considerably high. About 85-95% of the added ammonia was assimilated by yeast and removed from the must during fermentation. Addition of an adequate amount of ammonia in the maceration treatment gives a fine cider which has an adequate acidity and no abnormal constituent or flavour.

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Maceration treatment of milled apple pulp in cider-making has some effects on the composition of the resulting juice and cider. Influences of maceration conditions on these effects were studied. With grated apple pulp, as compared with crushed pulp, only little decrease in malic acid content was caused during maceration, unless highly aerobic conditions, such as a large superficial areain contact with air, were provided. Extended duration of maceration largely decreased the malic acid content, but was liable to give unpleasant flavour and taste to the cider. Addition of sulfur dioxide up to 100ppm inhibited the malic acid decrease and lactic acid increase, but did not inhibit the succinic acid increase. Malic acid decrease was accelerated by warming the pulp. By cooling to 5°C the malic acid decrease was retarded and the volatile acidity of the juice was considerably increased. When flozen at -18°C, however, a rapid malic acid decrease occured after thawed. Tannins did not decrease during maceration with Jonathan variety apples, except when the pulp was treated highly aerobically or treated by freezing-thawing. The use of grated pulp and addition of sulfur dioxide appreciably increased the tannin contents.

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Carbonyl compounds produced during storage at 30°C for 3 months and by heating at 100°C for 2 hours were studied quantitatively. Carbonyl compounds present in various misoes were converted into their 2, 4-DNPHs.
The total carbonyl content and the carbonyl contents of volatile and nonvolatile fractions in unheated Sendai miso were 13.7, 2.8 and 10.9μmole per 50g of miso, and 38.3, 16.0 and 22.3μmole in heated miso, respectively. In this report, the carbonyl concentrations in cluded not only volatile compounds but also nonvolatile ones.
Color tone of Sendai miso became darker during storage rather than by heating. On the other hand, concentration of volatile carbonyl compounds produced during heating were higer than those produced during storage. Moreover, the products formed in the stored miso differed from those in the heated miso; furfural was formed at 100°C but not at 30°C.

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This study aimed at clarifying the causes of the off-flavor which occurred during the process of concentratin Satsuma mandarin orange juice. As linoleic and linolenic acids were previously found in the lipids of Satsuma mandarin orange, its lipoxygenase activity was investigated in correlation to the ripeness of the fruit in the year 1973-4 and 1974-5. The fruits were periodically collected from one settled Satsuma mandarin orange tree in Yamakita, Kanagawa prefecture.
The fruits were divided into two parts: the carpels and the albedo, each of which was extracted with phosphate buffer(pH 7.0), followed by the precipitation of the enzyme with alcohol(final concentration 20%). The lipoxygenase activity was measured by the ultraviolet absorption method.
The moment when the lipoxygenase activity in the carpels reached maximum was in the middle of November or early December, which was4or8weeks earlier than the time when the degree of ripeness reached maximum. The ripness was evaluated from the ratio of sugar content of sugar content to citric acid content.

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Capsaicin was isolated from capsicum fruits by n-hexane-60% acetic acid extraction system. UV absorption maxima were found at 281nm(E^1%_1cm=98.8)and 231nm(E^1%_1cm=246)in ethanol, and at 246nm(E^1%_1cm=330)and 295nm(E^1%_1cm=139)in 0.5N NaOH. Modified UV method and standard addition method gave the same determined values. UV method, however, gave the 10% higher capsaicin content than the former two methods. While colorimetric method gave 2 to 3% lower content. The reason why UV method gave higher value was revealed that lower extracting ratio of capasaicin in the process of preparation was employed for the determination.
The correlation coefficient between scoville heat units(S)and the values determined by modified UV method(D)was 0.991. The relation was shown by S=10⁴×(21.79D+0.50).
Threshold level of pungency of capsaicin in 5% sugar solution was 0.04 to 0.05ppm.

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The mixture of water soluble synthetic monomers and invertase solution was frozen in dry ice/acetone and radiocopolymerized by gamma-ray. The characteristics of resulting polymer which was the membranous immobilized invertase were investigated succeeding to the former report.
Following results were obtained.
1) There was no significant difference in the Km value between native and immobilized invertase.
2) A decrease in activity of immobilized invertase was accompained by an increase in enzyme concentration and it was 8.5 to 91.5%.
3) Immobilized invertase showed good stability in a dry state even if it was stored at 35°C. The residual activity was about 74 to 95% after 60 days storage and about 80% after 130 days storage.
4) After the repeating usage for 30 times, immobilized enzyme showed about 70% of activity comparing to the original preparation.
5) Invertase became more stable to aniline and urea when immobilized but it became more labile to ethanol, guanidin, Hg and Cu.

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An investigation on the hydrolysis of sucrose solution by membranous immobilized invertase was conducted and the following results were obtained.
1) Sucrose solution(10 to 40% w/w)were decomposed completely by the immobilized invertase in a small reactor.
2) The immobilized invertase was repeatedly used in a reactor to decompose 10% sucrose sulution and there was no significant change in the decomposition pattern of substrate even after 30 times usage.
3) 30% sucrose solution was decomposed completely by the immobilized invertase column at the flow rate of SV3 to SV4.
4) The enzyme column was continuously operated and 30% sucrose solution was completely hydrolyzed up to 47 days at the flow rate of SV1.

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Spaghetties were stored under normal condition and at high room temperature(36-39°C), for one year, and qualitative changes were studied.
Spaghetties stored under normal condition showed gradual improvement in cooking loss and cooking quality during the whole storage period. On the other hand, in the case of samples stored at high room temperature, cooking loss and cooking quality were greatly improved during the first three months, and disimproved after this period. Brownish color deterioration was observed in this sample during the whole storage period.

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