Fresh royal jelly (abbreviated as RJ) was stored at various temperatures, -40°C, 5°C and room temperature, and the changes in physical properties and chemical compositions of RJ were investigated. The results were as follows: (1) Color and viscosity of RJ stored at -40°C did not change but those of RJ stored at 5°C and room temperature changed considerably. A remarkable change was observed when the RJ was stored in bright place at room temperature. (2) The ratio of waterinsoluble nitrogen to total nitrogen in RJ stored at 5°C and room temperature increased and the increasing pattern of this ratio was just the same as that of viscosity. (3) When fresh RJ was stored at 5°C and room temperature, there was an increase in its acidity, but the amounts of 10-hydroxyΔΔ²-decenoic acid, 10-hydroxydecanoic acid and gluconic acid in carboxylic acids of RJ were constant regardless of the storage conditions. (4) The total amount of free amio acid of RJ stored at room temperature and 5°C decreased with time and its amino acid composition changed. (5) Glucose oxidase activity significantly decreased at higher temperature. The lowering of glucose oxidase activity was found to be similar to that of the amount of water-soluble nitrogen. (6) The increase of viable count of RJ stored under various conditions was not found, and the viable counts were 1010²-10³. The quality of RJ was stable in view of microbiology.

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The operating parameters inside the extruder were devided into temperature, pressure and shearing action. The relationships between the gelatinization of starch and these parameters were investigated. Regardless with the temperature and the kinds of samples, the slopes of these P-Q (pressure-flow rate) curves were found to be about 2.5 when the samples flowed under high temperature and pressure. The gelatinization ratios of low moisture starch samples were 75-80% when they were treated under the conditions of 150°C, 20min and 400kg/cmcm² load in a closed cell. However the gelatinization ratios of the same samples were higher than those obtained under the above conditions by 5-15% when they were pressed out through a die with strong shear force after treating under milder conditions than the above mentioned.

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Distribution of microorganisms in unpasteurized Satsuma mandarin (Citrus unshiu Marc.) juices and changes of viable counts of the juices during storage were investigated. Viable counts were determined on Briggs agar for bacteria, and on YM agar and on Orange serum agar for yeasts and molds. Viable counts of bacteria in the juices were 10-10⁶/ml and decreased markedly after a month both during storage at 1°C and at 5°C. Viable counts of yeasts were 1010²-10⁶/ml and increased after a month both during storage at 1°C and at 5°C. The yeasts isolated from the Satsuma mandarin juice samples were identified by the procedure of Lodder and Kreger-van Rij. Candida was isolated from all the samples tested and predominated in yeast flora of greater part of the samples (7/13 samples). Other genera widely distributed in juices were Saccharomyces, Kloecken and Torulopsis. Most of the bacteria isolated were Leuconostoc mesenteroides and the others were gram negative rods. Molds detected were very few on all the samples tested.

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Intermediate moisture meats were manufactured from porcine loin using commercial procedures and with varying levels (2%, 4%, 6%, 8%, 10%) of NaCl. To study the changes of proteins in intermediate moisture meats, water activity, moisture content, salt concentration and extractability of proteins were investigated during curing and smoking. During the process of curing, the salt concentration in meat increased while the moisture content and water activity decreased. These changes were very rapid in the first 3 days of curing. The product, which was cured for 9 days, has been subjected to smoking (15°-20°C). As a result the water activity decreased rapidly. The extractability of proteins has been observed at the same time. SDS-PAGE shows that changes in extractability of water soluble proteins are less noticeable while the extractability of structural proteins depended on curing and smoking period. SDS-PAGE shows that the extractability of myosin decreased with increasing curing and smoking period. Changes in extractability of actin, tropomyosin and α-actinin seem to be not much. Electron micrographic observations show thateven after 9 days of curing the typical ultrastructure of the myofibrils is clearly visible. But when cured meat is smoked for 4 days, the structure of the thick filament and Z-line appears to be under-going disorganization. After 8 days of smoking the structure of muscle has undergone a greater degree of disorganization. However, the actin filaments are still organized.

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Roasted and ground soybean ("Kinako" in Japanese) and ground soybean ("Daizuko" in Japanese) were stored under several temperatures (25, 5 and -25°C) for five months to investigate the oxidation of total lipids. The following results were obtained: (1) Acid value, peroxide value and carbonyl value of total lipids extracted from "Kinako" and "Daizuko" increased, while iodine value decreased by long storage. The change was observed at each temperature, remarkabley at higher temperature. The changes of total lipids in "Daizuko" were more notable than those in "Kinako". There was a prominent difference between those of "Kinako" and "Daizuko" after five months storage. (2) Compound lipid content in total lipids decreased, while neutral lipid content increased as storage period became longer. Furthermore triacylglycerol content in neutral lipid fraction, and phosphatidylcholine, phosphatidylethanolamine contents in compound lipid fraction showed a tendency of decrease during storage as compared with other lipid contents. (3) According to the study on the changes of fatty acid compositions in total lipids, neutral lipid fraction and compound lipid fraction, 18:2 and 18:3 acid contents decreased, while saturated fatty acid content in total acids increased with longer storage period. The changes above mentioned were observed in both samples, "Kinako" and "Daizuko", and the oxidation of total lipids in "Daizuko" were more remarkable than that in "Kinako". Moreover the oxidation of lipids in "Daizuko" were evident with higher temperature and longer period of storage.

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Mechanical properties of waxy rice cake, "Mochi", in the high temperature range, 40-100°C, were examined using a coaxial cylindrical rheometer. The dynamic modulus G of shiratama mochi cake decreased rapidly as increasing the apparent specific volume in a relatively lower temperature range, 45-60°C. The activation energy in this range was about 70 kcal/mol. The dynamic viscosity η showed the similar tendancy to G. Repeating extrusion of mochi cake made G lower slightly at high temperatures above 65°C. No effect of aging period was observed during 3 days to 4 weeks. Both G and η of shiratama mochi cake were substantially lower than those of commercial mochi cake. On the basis of these experimental results, the energy balance during oscillation was discussed in relation to texture. The new index, ΔK/K', loss energy ratio, was introduced, which defined by following equation: ΔK/K'=tanδ/(2+πtanδ), where tanδis loss tangent. The equation. is also applied to the material of very high viscosity. ΔK/K' which is defined in the range from 0 to 1, shows the degree of periodic damping. The properties indicated by ΔK/K' agreed well with the actual chewing characteristics of mochi cake.

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The effects of food emulsifiers on the spoilage of canned milk coffee inoculated with spores of three species of themophilic spore forming bacteria, Clostridium thermoaceticum, Bacillus stearothermophilus and Clostridium thermosaccharolyticum, were studied. (1) Under commercial sterilizing condition (F₁₂₁°C=20 to 30), addition of 500ppm of P-1670, sucrose monopalmitate, or S-1670, sucrose monostearate, inhibited microbial spoilage of canned milk coffee markedly. (2) Anti-spoilage effects of P-1670 showed twice as much as S-1670. (3) Polyoxyethylene sorbitan monopalmitate, polyglycerin monopalmitate and glycerin monopalmitate had no anti-spoilage effect.

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(1) Glycerol showed the remarkable stimulative activity on production of acetic acid and also reduced the lag time on growth of Acetobacter pasteurianus No. 2, when added to the basal medium. (2) No significant differences were observed between amino acid and fatty acid compositions in the cells grown on the basal medium and in the cells on the glycerol medium. Phosphatidylcholine, phosphatidylethanolamine, cardiolipin and ornithine lipids were detected in the phospholipid fraction obtained from Acetobacter pasteurianus No. 2 cells. (3) ¹⁴C-glycerol was incorporated considerably into cells at an early stage of the growth. The radioactivity was found to be distributed in membrane and particulate fractions other than cytoplasm fraction in the cells. In the particulate fraction, the radioactivity was significantly detected in the phospholipid fraction. The radioactive phospholipids were separated into three fractions by radiochromatography. The strong radioactivity was discovered at the same Rf value as that of authentic phosphatidylcholine. (4) These results suggest that glycerol play an important role in the phospholipid synthesis of acetic acid bacteria.

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A rapid and convenient method based on conductometry is applied to flow injection analysis for measuring salt content in food. The development of a flow system was investigated for determining the salt content in processed foods with added salt. A linear correlation between the peak conductivity and the salt content was obtained with high correlation coefficient (r=0.9998). It is possible to analyze about 70 samples within an hour using the method, and the coefficient of variation for 10 successive injections was 0.22%. The proposed method is very simple and rapid, and it requires no amount of skill in measuring.

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Butter beans imported from Burma are mainly processed to "Ann" in Japan. Significant amounts of cyanogenic glycosides are contained in the beans. This work was carried out to identify cyanogenic glycosides in them. Cyanogenic glycosides in butter beans were extracted with 80% ethanol, and isolated by silica gel chromatography with chloroform-methanol (5:1) solvent. Two cyanogenic glycosides were obtained as crystals. These glycosides were analyzed by GC, FD-MS, PMR and IR. Two cyanogenic glycosides were identified to be linamarin and lotaustralin. The former was main cyanogenic glycosides in butter beans.

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