Soybean milk prepared commercially by aseptic packaging system was stored at 5, 25 or 37°C for a period of two months. The quality of the stored soymilk was evaluated by determining microbial count, oxidation-reduction potential (ORP), chemiluminescence and free amino acid contents. Soymilk was also subjected to Color Test and organoleptic evaluation. No micro-organism was detected in the stored soymilk, indicating the high efficiency of the process. Organoleptically, soymilk deteriorated during storage. Significant deterioration was observed (at P<0.01) in soymilk stored at 25°C for 2 months or at 37°C for half a month. Color also changed from yellowish to whitish or faded. The pH of soymilk decreased fairly immediately after storage. The ORP of the aseptic soymilk stored at higher temperatures (25 and 37°C) decreased, while the chemiluminescence count increased during storage. No change was observed in the composition or contents of free amino acids. However, ammonia contents increased during storage and were found to be well correlated with storage period and storage temperature. Therefore, it can be concluded that the determination of ammonia content could be used as an index of quality evaluation of aseptic soymilk.

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The volatiles produced in a commercial aseptically prepared soymilk stored at 5, 25 or 37°C for 2 months were examined and identified using gas chromatography and gas chromatography-mass spectrometry. Fourteen of volatiles including acetone and n-pentane were detected. Contents of acetaldehyde, acetone, n-pentane and n-hexanal increased and were found to be well correlated with storage temperature and storage period. The increases of acetone and n-pentane were especially remarkable, as that acetone content in soymilk increased by about 15 times on storage at 37°C for 2 months, and n-pentane content increased by about 17 times. Moreover, acetone was major component of the volatiles. Consequently, it was suggested that the acetone content of soymilk can be used as an index of quality evaluation of the aseptic soymilk. Shelflife of the aseptic soymilk was also investigated by measuring acetone and ammonia contents as indices.

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Beat seasoning was prepared from waste juice of beat sugar refining process by alkaline hydrolysis. The volatile compounds of heated and non-heated beat seasoning were identified by GC and GC-MS methods and their aroma patterns were compared. (1) Among 13 compounds identified in the non-heated seasoning, lactones, cyclotene and vanillin give the unacceptable flavor for seasoning. (2) Forty three volatiles were identified from the heated beat seasoning. Besides the identified compounds in the non-heated seasoning, 3-methylbutanal, sulfur containing compounds, pyrazines and methoxy phenols were found to contribute to the characteristic smell of the heated seasoning.

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Parboiled rice is a kind of processed rice that is produced in some countries of Asia, principally India, as well as in Europe and America. Parboiling process involves the hydrothermal treatment of paddy befor milling. This investigation was carried out to determine the effect of parboiling process on physical properties of brown rice. The parboiled rice was produced by medium scale equipment. The results obtained were as follows. (1) The thickness, bulk density and whiteness of brown rice decreased with increasing the integrated gelatinization temperature. (2) The fissures of brown rice were developed in the range 400-1000 (°C·min). (3) The cracking hardness of brown rice increased with increasing the integrated gelatinization temperature. (4 ) The free fat acidity value of parboiled rice stored for 25-30 days was lower than that of untreated rice under the same conditions.

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Penetration and extraction (desalting) of various salts in tuna flesh had been studied under various conditions in our previous paper. In this study, tranfer rates of NaCl have been measured for flesh of river chum (pre-spawning river chum salmon) and ocean chum (pre-spawning chum salmon caught in the North Pacific Ocean), in comparison to tuna flesh and the penetration rates into both salmon flesh through skin have also been evaluated. Observed concentration distributions and amounts of penetrated salt in flesh were explained by FICK's law of diffusion. And for both direction of diffusion, parallel to or perpendicalar to fiber, there were no differences in mechanism and in diffusivities. As flesh, especially in river chum, swelled and shrank in contact with certain concentration of salt solution, the amount of salt per unit volume of swollen flesh in equilibrium were used as surface concentration in the above calculation. And this treatment was certified experimentally in short time penetration. The rates of penetration into both flesh through skin were also expressed by diffusion in composite media and by diffusion accompanied surface resistance. The diffusivity of NaCl in the skin of river chum was larger than the other one, but its over-all resistance through skin was also larger caused by its larger thickness of skin.

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The relationships between four fermentation conditions (mixing temperature, fermentation time, punching of the dough and the final proofing time) in french bread production by the straight dough method and flavor substances in the crumb and the crust of the french bread were investigated using the experiment of orthogonal L8 design. The amount of alcohols in the crumb decreased as the final proofing time was shortened, but the alcohols in the crust were not affected by any of the factors. The total amount of iso-butyl alcohol and acetone in the crumb was increased by the punching and raised mixing temperature. The acetaldehyde was increased by reducing mixing temperature and fermentation time, while it was decreased by the puching and increased final proofing time. The amount of acetone in the crust increased by reduced fermentation time, while it was decreased by punching and by longer proofing time. The diacetyl was decreased as the mixing temperature was raised. It is suggested that the carbonyl compounds in the bread were formed mainly during the baking process, from the results that the crust contained a larger amount of carbonyl compounds than the crumb.

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It is well known that residual fats and salts in whey protein concentrate (WPC) affect its functional properties, i.e. foaming, gelation and so on. We investigated the effects of NaCl, CaCl2 and fats on the heat stabilities of some WPCs prepared by ultrafiltration (UF), microfiltration (MF), dialysis (DI) and ion exchange by carboxymethyl cellulose. The results showed that desalting was effective for the improvement of heat stabilities of whey protein, whereas defatting reduced the heat stabilities of whey protein at pH 5-6 and in the presence of high concentration of salts, especially Ca ion.

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Manufacturing conditions by combination of centrifuge, celite filtration and ion exchange resins in order to recover bland syrup from press liquor of Satsuma mandarin peel residue was studied. The results were as follows. (1) Press liquor yield of peel residue by adding 0.3% lime indicated 30.0%, which was more than twice compared with 11.3% of no adding lime. By adding lime to peel residue, pH, ash and total flavonoid content was increased and total sugar and amino-nitrogen content was not influenced. (2) In the case of removal of bitterness with ion exchange resins by batch method, HP-20, S-861 and WA-30 adsorbed 36.2, 35.2 and 30.9% of total flavonoid, respectively. On the removal of calcium, SK-1B and PK-218 eliminated about 80% of calcium. (3) On the continuous operation with the column method, the removal of bitterness by HP-20 treatment could be carried out within 4 hours, the removal of calcium by SK-1B and PK-218 treatment was within 3 hours and the decoloration by WA-30 treatment was within 3 hours, respectively. (4) On the combination of ion exchange resins and adsorbents, both (A) combination of HP-20, WA-30, SK-1B and WA-30 and (B) combination of WA-30, SK-1B, WA-30 and HP-20 was the best method. (5) Sugar components in press liquor estimated through extraction season were sucrose: 36.2-44.8%, glucose :26.3-31.0%, fructose: 25.3-28.5% and maltose: 3.7-4.9%. Total sugar content was the highest (11.3%) at the middle of January. (6) Volatile components in press liquor contained d-limonene, γ-terpinene, α-terpineol, linalool and α-pinene, and final sugar solution contained only 0.7% of total volatile quantities. (7) Final sugar solution, which was produced by manufacturing and concentrating press liquor, did not contain bitter taste, color and odor, and components of sugar was glucose: 33.5%, sucrose: 30.6%, fructose: 30.3%, and maltose 5.6%. (8) Recovery yield of final sugar solution was 11% to press liquor and 1.7% to Satsuma mandarin fruit, and total sugar content in final sugar solution was 60%.

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The fruit bodies of 113 kinds of mushrooms were examined by amino acid analyzer to determine 20 free types of protein amino acids and 11 non-protein amino acids. (1) Though considerable difference was often found among species of mushroom, the average of total free amino acids was 213μ mol/g dry matter. (2) It was found that the amount of alanine, glutamic acid and glutamine was very high and they were the dominant amino acids in the free amino acid pool. (3) Contents of non-protein amino acids were commonly low, but ornithine, γ-amino-n-butyric acid and cystathionine were proved to be widely distributed in the mushrooms. (4) So far as the present survey could determine, there seems to be no obvious correlation between the free amino acid pool and taxonomic groups of mushrooms.

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Fruits of 17 varieties belonging to 14 species cultivated in Japan were harvested at different maturities and those at commercial ripeness was stored at 20±3°C. The sugar content of these fruits and their composition were analyzed by HPLC and they were classified into several groups accordiing to the main sugar composition. The changes in sugar composition of the fruits were considered from various viewpoints. (1) Main sugars in fruits were composed of sucrose, glucose, fructose and sorbitol. (2) Sugar composition of the fruits at commercial ripeness was classified to following four categories: (a) Sucrose group, (b) Reducing sugar group, (c) Balance group and (d) Sorbitol group. (3) Total sugar content in fruits increased with the progress of harvest time, remarkably in sucrose content, but at full ripeness the total sugar and sucrose contents of most of fruits decreased, whereas those of melon and plum increased rapidly. (4) The total sugar contents of Japanese apricot, plum and melon decreased during storage and those of the other fruits slightly changed. It was considered that sucrose in most of the fruits examined was hydrolyzed during storage. Rapid hydrolysis of sucrose in persimmon was observed at the end of the storage period. Glucose content increased in 'Chojuro' pear and sucrose content increased remarkably in Satsuma mandarin. Reducing sugar in Japanese apricot and all composed sugars in plum and melon decreased. (5) Sorbitol content in fruits increased with the progress of harvest time and decreased during storage.

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