Sitophilus zeamais Motschulsky and S. oryzae Linne are main cereal insect in Japan. These two insects were irradiated by gamma ray from Co-60. The dose to kill the insect within three weeks after the treatment, the dose to stop the adult emergence from each development stage and the dose to sterilize were determined.
Seven days old adults were irradiated and the mortality after three weeks was determined. LD₉₉ and LD₅₀ was 7.5Krad and 4Krad for S. zeamais and 8Krad and 5Krad for S. oryzae.. S. oryzae was a little bit more resistant against gamma irradiation than S. zeamais.
When pupae larvae and egg were irradiated, there was not so much differences in the sensitivity between these two species.
Comparing each development stage, they became more resistant in accordance with the age.That is the sensitivity was increased in the order of adult, pupae, larvae and egg.
It was also found the younger egg was more sensitive to radiation and all eggs were killed by 4Krad. All the emerged progenies from each stage irradiated 10Krad were sterilized.
After all, these insects were suppressed by the irradiation of 10Krad.

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The samples of starch were studied by thermal analysis. The thermal analysis showed that the changes were observed at 160°C and remarkably at 220°C. The roast flavor was also appeared at 160°C by olfactory analysis at exhaust pipe of thermal-analyser.
The flavor components of roasted starch were trapped and fractionated into sodium bicarbonate soluble fraction, sodium hydroxide soluble fraction and neutral fraction. Each fraction possessed characteristic flavors and among those, the sodium hydroxide fraction possessed fragrant odor.
The carbonyl compounds of roasted starch were converted to 2, 4-dinitrophenylhydrazones, which were fractionated into neutral 2, 4-DNPHs and acidic 2, 4-DNPHs. Neutral 2, 4-DNPHs and acidic 2, 4-DNPHs were successively subjected to direct gas chromatography and also thin-layer chromatography. The following nine carbonyl compounds and four oxo-fatty acids were identified; methanal, ethanal, propanone, 2-methylpropanal, butanone, 3-petanone, furfural, acetylfuran, 5-methylfurfural; glyoxylic acid, pyruvic acid, α-ketobutyric acid and levulinic acid.
2, 4-DNPHs of 5-hydroxymethylfurfural was also isolated and identified, and further bis-2, 4DNPHs of glyoxal, pyruvaldehyde and diacetyl were detected by thin-layer chromatography.
These carbonyl compounds have chraracteristic flavor, which are supposed to be concerned with the flavor of roasted starch.

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The sodium hydroxide soluble fraction of the flavor of roasted starch has characteristic fragrant odor, and this fraction was subjected to gas-liquid chromatographies and gas chromatographmass spectroscopies.
As sweet fragrant flavor, 5-methylcyclopent-2-en-2-ol-1-one and maltol were separated and identified by MS and IR spectroscopies and these compounds have so-called "sugary flavor".
The following five phenolic compounds; phenol, m-cresol, pyrocatechol, resorcinol and homocatechol, were identified by MS spectroscopies. These phenolic compounds, especially homocatechol, have strong characteristic smoky flavor which are supposed to be concerned with flavor of roasted starch.

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The sodium bicarbonate soluble cornponents of the flavor of roasted starch have strong acidic, but fragrant flavor. Therfore this conponents are considered to play a significant role in the flavor of roasted starch.
This acidic components were subjected to direct gas chromatographies, to identify the following nine volatile fatty acids; acetic acid, propionic acid, iso-butyric acid, iso-valeric acid, n-valeric acid, crotonic acid, iso-caproic acid, n-caproic acid.
This fraction obtained here contained many components and then column chromatographic fractionation was preliminarily carried out to facilitate the practicing of GC-MS spectroscopies. The following seven organic acids and two enolic compounds were identified by GC-MS spectroscopies; benzoic acid, 2-furoic acid, succinic acid, methylsuccinic acid, fumaric acid, glycolic acid, oxalic acid; maltol and 5-methylcyclopent-2-en-2-ol-1-one.
These compounds identified here are supposed to be concerned with flavor of roasted starch.

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In the manufacture of "Tenobesomen" a small amounts of cottonseed oil or soybean oil is added to wheat flour, and after prepared dried noodle it is kept in a room of high humidity for several weeks. This process is called "Yaku".
Analysis of the ether extract of the product showed the decrease in iodine value and the increase of peroxide value, and the yield of wet gluten of the product drops.
To clarify these phenomenon in "Yaku" stage, some experiments were carried out on the mixture of oils which contain polyunsaturated fatty acids and some kinds of protein in the ratio of 2:8, and observed that in high humidity oxidized oils react on protein resulting in browning of color and change of protein. In low humidity, in spite of the oxidation of oils was faster and severer both the browning and the change of protein scarcely happened.
It is supposed that in the period of "Yaku" oxidized oil react with wheat gluten and makes the noodle more delicious.

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In order to compare characteristics of several evaluation methods of physical properties of Kamaboko, which express "Ashi (Jelly Strength)" quantatively, 7 brands of Kamaboko were tested by Food-Rheo-meter, Jelly-Strength tester and Tensilon. Relation between these characteristics and evaluation by sensory test were also compared.
The results were as follows:
1) In the tensile test by Food-Rheo-meter, fairly high relation to Shimizu's empirical equation was found.
2) In the compression test by Jelly-Strength tester, relation to Fukushima's empirical equation was hardly found. But, for rising angle of penetration-load curve, both were highly related.
3) In the compression test by Tensilon, high relation to (h/l) of wedge-shaped plunger test curve was found.
Shimizu's equation is considered to be almost essentially the same with Nutting-Scott Blair's empirical equation to which Weber-Fechner's law is applied.

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Subsequently to the studies in the previous report, the author developed the methods of preparation of the quick ripened salted viscera utilizing some enzymes together with the admixtures of the homogenized liver and the hashed stomach of swine. The results of the studies are summarized as follows:
1. It was confirmed by the sensory evaluation that the particularly desirable mixture rates of the above-mentioned liver and stomach were from 60:40 to 70:30.
2. By the fermentation tests, it was confirmed that the quick ripened salted viscera was made by adding either papain at about 0.1g or pancreas at about 10g per 100g of the substrate of salted viscera, and then retaining for 24 hours at 30°C for fermentation; moreover, the salted viscera utilized pancreas was particularly desirable on the taste.
3. It was confirmed that the fishy odor of the salted viscera was almost perfectly deodorrized by the pasteurization of 40 minutes at 75°C.
4. To the raw materials of the salted viscera, the addition of potassium nitrite at 60ppm, or sodium nitrite at about 30-60ppm was exceedingly available in order to prevent the browning of the salted viscera owing to the pasteurization and other.

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