In order to clarify target organisms in thermal processing for canned foods, the frequency of species of spore-forming bacteria appeared in spoilage problems during 1968-1980 was demonstrated for each food category. Bacillus subtilis and B. licheniformis were isolated frequently in every food categories, especially in sweet confectioneries (pH 5.6-6.5), except fruit products. The other species frequently isolated were Clostridium pasteurianum for fruits (pH 3.5-3.9), C. thermosaccharolyticum for vegetables (pH 4.4-6.3), C. sporogenes and B. coagulans for fisheries (pH 5.2-7.4), C. sporogenes for cured meats (pH 6.2-6.8), B. coagulans for formulated meals (pH 5.0-6.2), and C. thermoaceticum for low-acid soft drinks (pH 5.8-6.2), such as coffee containing milk which was to be distributed under a high temperature above 50°C.

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Some factors influencing on phosphorylation of soybean protein were investigated. The extent of phosphorylation was dependent on addition rate of phosphorus oxychloride. It was difficult to complete the phosphorylation with high addition rate. In addition, the extent of phosphorylation was affected by concentration of protein. Owing to high viscosity, more than 8% of soy protein isolate (SPI) solution was not able to be fully phosphorylated. Association of phosphate to SPI was stable after sterilization (140°C, 20sec). On the basis of these results, phosphorylated SPI was sterilized and spray dried. The powdered phophorylated SPI had the same high solubility at acidic region as that of the phosphorylated SPI solution before spray drying.

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Phosphorylated soy protein isolate (P-SPI) was spray dried and the properties of powdered PSPI were investigated. The P-SPI powder was soluble at wide pH ranges and had good gel formiing and emulsifying abilities. In addition, P-SPI powder had good functional properties which were not observed in SPI. P-SPI solution kept high solubility even after freezing and thawing. P-SPI powder was soluble in high saline solution (10% NaCl). These properties are very interesting as food materials.

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In order to examine the effect of anions on the gelling ability of kappa-carrageenan, measurements of stress relaxation, dynamic viscoelasticity and differential scanning calorimetry were carried out on kappa-carrageenan gels containing NaF or NaCl or NaBr or NaI. The concentrations of sodium salts ranged from 0.1 to 2.0M, while the concentrations of the gels were varied from 2 to 5% (w/w). It was found that (1) Dynamic Young's modulus E' became maximum at 0.2M sodium salt. The order of the maximum value was E'_max(F^-)>E'_max(C^-)>E'_max(Br^-)>E'_max(I^-). (2) The relaxation spectrum of kappa-carrageenan gels containing F^- or Cl^- or Br^- was quite different from that of kappa-carrageenan gels containing I-. (3) The temperature of the endothermic peak accompanying the melting of kappa-carrageenan gels which contain sodium salt shifted to higher temperatures with increasing concentration of sodium salts. The order of the maximum endothermic heat ΔHmax evaluated from the area under the endothermic curve wasΔH_max(Cl^-)>ΔH_max(Br^-)>ΔH_max(I^-). It is concluded that the effect of anions on the gelling ability of kappa-carrageenan is more remarkable in anions with small Pauling's radius than in anions with larger radius.

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In our previous paper, we showed that desalting improves heat stability of whey protein concentrate (WPC) effectively and defatting reduces it at pH 5-6, the range of isoelectric points of major whey proteins, or under high ionic strength. When WPCs are used as food ingredients, it is very important to evaluate their functional properties, such as gelation and foaming, as well as solubility and heat stability. We studied the effects of desalting and defatting on gelling and foaming propeties with some WPCs in this report. Partially defatted WPC (MF-WPC) prepared with microfiltration (MF) formed harder gel than normal WPC with or without the addition of NaCl by heating. However, its gel prepared with CaCl2 had rougher gel matrix and its cohesiveness was reduced. Water holding capacity of heat-induced WPC gels increased by desalting. Defatting was more effective to improve the foaming property of WPC than desalting.

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Changes in several components of synthetic and natural medium were measured during acetic acid fermentation. (1) Effective substances such as glycerol, lactic acid, L-alanine, L-aspartic acid and D-glucose, were supplemented to the basal medium respectively. Decrease of glycerol was more than any other substances and was remarkable in the early stage of the fermentation. L-alanine enhibited slight decrease, and L-aspartic acid was converted to L-alanine in the early stage of acetic acid fermentation. (2) In the three kinds of natural medium, including sake cake, yeast extract and non-salt soybean miso, glycerol content showed a remarkable decrease in all of the media tested. Among the non-volatile organic acids, significant decrease of lactic acid content was observed in the yeast extract medium, whereas the amounts of succinic and citric acid were hardly changed. As the acetic acid fermentation progressed, total amino acid contents decreased gradually in all of the media tested. In particulary, glutamic acid, aspartic acid and serine contents decreased considerably at the early stage of acetic acid fermentation.

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In this paper, we studied on the seasonal changes in sucrose contents and activities of the acid and neutral invertases in stalks and leaves of two varieties of sugarcanes, 'Chikusha' (Saccharum sinense Roxb. cv Chikusha) and 'N:CO 310' (S. officinarum L. cv. N:CO 310). The former is used as a material of "Wasanbon" sugar, whereas the latter is also used as a material of commercial refined sugar. The main purpose of the study is to investigate the seasonal accumulation of the basis of acid and neutral invertase activities in the sugarcanes. The highest activity of the acid invertase was observed in the top internode section of the stalks during the rapidly growing season. The greater activities of the enzyme were found in the leaves of the upper parts of the stalks in both varieties. On the other hand, the neutral invertase activities were found to be higher in the lower parts than in the upper parts of the stalk. Sugar content of the stalks in 'Chikusha' sugarcane was considered to reach the maximum values in October because of the observed decrease in the activities of the invertases in this season, but that in 'N:CO 310' sugarcane showed the maximum value in November. The sugar accumulation in stalks of both varieties increased from base to top.

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The effects of fermentation conditions, such as mixing temperature, fermentation time, punching of dough and final proofing time during french bread production by the straight dough method, on products were investigated using the experinent of orthogonal L₈ design. The pH values of products showed higher value at lower mixing temperature, shorter fermentation time and not affected by punching and final proofing time. The T.T.A. (total titratable acibity) of the products showed higher value with raising mixing temperature and longer fermentation time. Not only the final but also the punching affected considerably the specific volume of the products. Monosaccharides were almost not remained in the products. The residual disaccharides in them showed lower level at longer proofing time. Decreasing the mixing temperature and the fermentation time tended to show higher level of residual free amino acids in the breads.

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Organic acid and free amino acid compositions affecting for processing of "Mume" fruit (Prunus mume SIEB. et ZUCC.) were analyzed in relation to variety or growth and developement of fruit portions. Results obtained are as follows: (1) Organic acid and free amino acid contents changed conspicuously with fruit growth and development. (2) Total free organic acid contents of fruit flesh in all 26 varieties varied from 4.2 to 5.5% at the end of three stages of harvest maturity. (3) The organic acids of the fruit flesh were citric, malic, oxalic, succinic, fumaric and three kinds of unknown acids. And their contents were quite different among variety or harvest maturity. Citric acid and malic acid was predominant acid in common types or apricot types of "Mume" fruit at the end of harvest maturity, respectively. (4) Free amino acids in the fruit flesh increased with fruit growth, followed by decrease after optimum picking time. But in the stony endocarp and kernel, amino acid content decreased gradually with fruit growth and their hardening. (5) Twenty or 22 amino acids were detected in all fruit portions of flesh, stony endocarp and kernel, and asparagine accounted for 80-91% in flesh at all stages of maturity. Stony endocarp and kernel contained much more arginine, serine, glutamic acid, glutamine and alanine than fruit flesh, causing decrease in the percentage of asparagine content to 66-67% in stony endocarp and 33-35% in kernel at the end of harvest maturity. (6) Free amino acid contents in the main three varieties did not change appreciably throughout the optimum picking time.

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Effects of variety and harvest maturity of "Mume" fruit (Prunus mume SIEB. et ZUCC.) on the yield and composition of juice extracted by osmosis of high concentration of sugar solution were investigated in connection with fruit growth and the changes of some chemical compositions for three years through 1981 to 1983. The results obtained are as follows: (1) Juice yield percentage of the fruit showed a decreasing tendency with fruit growth and development, but juice yield per fruit increased gradually untill the optimum picking time. (2) In all of the 26 varieties used, about 55% or more of the juice yield percentages were obtained, and juice yield per fruit rised with an increase in size of the variety. (3) Organic acid and free amino acid compositions extracted with sugar solution were paralleled to those of the fruit of raw materials. But the extraction rates of organic acid and free amino acid with sugar solution decreased with fruit growth, showing about 40% at optimum picking time. (4) It was possible to decide that the optimum picking time for juice extraction was in the duration from 105 to 110 days after full bloom in the case of standard variety 'Nanko'. (5) It was also found that the blending of fruit puree made from fully ripened fruit improved the quality of diluted solution of juice extracted with sugar solution.

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