A strain of soil bacteria was isolated by plate culture with soybean hemicellulose B, and was identified as Bacillus pumilus No.24. The hemicellulase was extracted from the supernatant fluid of the submerged culture, and fractionated on a CM-Cellulose column and on a Biogel P-60 column. The characteristics of the enzyme were as follows; optimum temperature was about 50°C, and optimum pH was 5.5. The enzyme was stable at 40°C. The enzymatic hydrolysate of soybean hemicellulase B was fractioned on a Sephadex G-15 column and its paper chromatogram showed to contain two kinds of spot. After extraction of those substances for acidic hydrolysis, arabinose and galactose were proved to be the constitutive sugars of both those substances.

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The renaturation in the quarternary structure of major protein component was observed by gel electrophoresis, when the soybean protein was neutralyzed to pH 8.6, after heating at alkaline or acidic pH, under which the conformational change occured.
The difference spectra and ORD measurement in isolated 11S protein solution showed that the protein was renatured almost completely by neutralyzing the protein solution treated at the pH below 11.22 and partially renatured by neutralyzing the protein solution treated at the pH over 11.22 or at pH 2.35.

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Changes in HMF content of honey caused during heating and storage were examined.
(1) Only slight increases in HMF content of honey samples were observed when they were heated at 50°C for 24 hours or at 60°C for 10 hours.
(2) Change in HMF content of honey caused by heating was variable depending on the kind of honey sample. Honey samples of lower pH and weaker buffering action were found to produce more HMF on heating.
(3) When honey samples were stored at a low temperature (below 10°C), no increase of HMF contents was observed. When stored at room temperature (May-November), their HMF contents increased only slightly. When stored at 36°C, however, they showed an appreciable increase in HMF content.
(4) Change in HMF content of honey during storage was also variable depending on the kind and quality of honey sample. Domestic honey from Renge-so (Chinese milk vetch) showed less increase in HMF content during storage than did imported honey samples.
(5) The change of HMF added before storage was investigated during storage. When stored at room temp., the amount of HMF decreased first, and at 36°C, it decreased first followed by a gradual increase.
(6) When citric acid was added to honey samples, their HMF contents increased more markedly than that of the control without added citric acid: at higher temperatures, the effect of added citric acid was more pronounced.
(7) Addition of proline or ferric compound to honey samples showed no effect on their HMF contents during storage.

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Changes in diastatic activity of different honey samples during heating and storage were examined.
(1) Diastase numbers of domestic, imported and commercial honey samples were measured.
(2) Changes in diastase number (DN) of honey samples during heating at 50, 60, 65 and 70°C were investigated. At 65°C they showed a low DN already after 3 hours, while at 50 and 60°C their DN did not show any significant change after 10 hours, although they reached a low level after one or two days.
(3) Many honey samples showed DN less than 8 when stored at 36°C for about 5 months. When stored at room temperature, their DN decreased slightly. Change in DN was variable depending on the kinds of honey samples. Samples showing a high pH level and a strong buffering action were found to show relatively slight decrease in DN.
(4) Based on the results it was concluded that the DN of honey sample can be used as a criterion of the extent of addition of quasi-honey as well as the extent of heating of the sample.

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Hardened soybean oil, beef tallow and hardened whale oil with various proportions of lecithin were tempered at 25°C for 24, 120 or 240 hr, and creaming value and water-sorption index of the products were measured. Among the fats without lecithin, hardened whale oil showed the highest creaming value followed by beef tallow, hardened soybean oil in this order. Creaming value increased with tempering time. However, creaming value decreased by addition of lecithin with no effect of tempering. With the increasing quantity of lecithin, water-sorption quality was improved and the effect of tempering was recognized in the case of hardened whale oil.

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The effect of four kinds of emulsifiers on the creaming and water-sorption quality in edible solid fats was investigated. Addition of Homotex or Tween 80 increased the creaming value and showed the effect of tempering. Although the samples added with Span 80 or Span 20 showed no different tendency from control which did not contain emulsifier at the initial stage of creaming but showed good continuance.
Hardened soybean oil and hardened whale oil added with Homotex showed good water-sorption quality but beef tallow did not. Addition of Span 80, Span 20 or Tween 80 was undesirable for water-sorption quality and there was no effect depending on the amount of emulsifiers added.

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Viscosity, spinnability and gel forming ability were observed on the alkaline solution of soybean protein under high protein concentration and high pH value. Gelation of dealkalized solution occured at above 8% of protein concentration and among pH range 11.5-12.5, spinnability appeared above pH 12.0 and it seemed to be necessary that molecular interaction was as small as possible. Viscosity of alkaline dope solution was not so much related to these properties.

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Volatile components were obtained from raw tea (Ban-cha) and roasted green tea by vacuum distillation followed by ether extraction for gas liquid chromatography using capillary column.
The production of pyrazines, furans and pyrroles was remarkable during roasting of green tea indicating they have important contributions to the aroma of roasted green tea.
Two isomeric 2, 4-heptadienals were newlyidentified from volatile components of green tea before roasting. These compounds were remarkably decreased during roasting.

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