In order to obtain the basic knowledge on the industrial application of the spray drying method of agar-agar, the aqueous agar extract from Gelidium pacificum OKAMURA, a typical red algae for agar-agar manufacture, as well as the aqueous agar solutions of commercial powder agar which were mostly processed from the alkali treated Cracilaria species were Spray dried by an experimental spray drier.
Generally, no distinctive reduction of melting point and jelly strength was observed by the spray drying Process at the input air temperature of 130°C. However, jelly strength was affected by the spray drying Process at 150°C input air temperature. The spray dried products were consisted of hollow granules of which diameters are 3 to 100 microns. The economical anticipation as well as some other technical problems were also discussed.

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The behavior of nucleotides added to milk or cheese curd during the cheese manufacturingwas investigated.
The nucleotides and orotic acid were shown to be stable against heat treatment at 63°C for 30 min. or 115°C for 15min. But, the most part (more than 90%) of the added nucleotides (disodium salt of 5'-inosine monophosphate or 5'-guanosine monophosphate) to milk was lost into whey, leaving only the small portion in cheese curd. By dipping the cheese curd in brine containing 0.215% each of nucleotides for 48hr. at 5°C, about 0.038% nucleotides were infused in cheese curd. About 30 to 40% of these nucleotides in cheese curd was lost gradually during 4 months' ripening. That the decrease of 5'-inosine monophosphate was more rapid than 5'-guanosine monophosphate is possibly due to the preferential utilization of the former by lactic acid bacteria.
These results suggest that the addition of nucleotides to cheese will be accomplished more effectively in process cheese than in natural cheese.

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Nucleotides (disodium salts of 5'-inosine monophosphate and 5'-guanosine monophosphate) were added to process cheese and their stability in the cheese during storage at 4±1°C and the effect on the taste of process cheese were investigated.
Nucleotides added to the process cheese were more stable during storage than in natural cheese. The heat inactivation of alkaline phosphatase and the pasteurization of microorganisms may be the reason for it.
Gouda and Cheddar cheeses ripend for 1 or 3 months were made to process cheeses with and without the addition of the various amount (0.006 to 0.05%) of nucleotides, and these cheeses were tasted by 45 persons. About one third of them could not distinguish the nucleotides-added cheese from blank cheese (cheese without nucleotides). But, persons who preferred the nucleotides-added cheese were generally more than those who liked blank cheese. The addition of nucleotides seemed to be more effective in ripened cheese than in young cheese, because a larger amounts of amino acid like glutamic acid, which was known to have the synergistic effect with nucleotides on enhancing the taste, was found in ripened cheese.

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From the viewpoint of soybean protein gel utilization for human foods, studies on the conditions affecting on the chewiness or physical properties of the gels were already reported by the author. In this paper, changes of the dye binding abilities and the amount of SH group of the protein during gel formation process were investigated.
Any changes on the dye binding abilities of the protein were not observed during gel formation process of protein pastes, in both cases of acid dye and basic dye.
The amount of SH group in protein extract from undenatured soybean meal was affected by heat treatment, and after the amount of SH group reached about maximum in the range of 50-80°C, the SH group decreased rapidly. SH group in the protein paste obtained from unheated extract also decreased with the heating temperature rapidly especially in the range of 60-90°C. But in the case of the protein paste from heated extract, the amount of SH group showed low level without depending on the heating temperature, and was equal to those of the protein pastes heated above 90°C from unheated extract.
Based on the above results, the structure of the protein network was discussed in relation to gel formation of soybean protein.

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The molecular species of 3-sn-phosphatidylcholine from soybean were determined after convertion into diglyceride acetates by means of hydrolysis with phospholipase C and acetylation with acetic anhydride and pyridine. The resultant diglyceride acetates were separated by thin layer and columnchromatography on silica impregnated with silver nitrate into 7 (LDGA-1-7) and 13 (LDGAA-L) differing with respect to their degree of unsaturation, respectively. Furthermore, the diglyceride acetates were separated by gas liquid chromatography on 3% -JXR on the basis of total carbon number of the fatty acids.
As the results, the amount of the 3-sn-phosphatidylcholine composed of total carbon number 36(16+20, 18+18), 34(18+16, 14+20) and 38(20+18) was abundant, and this accorded with the large amount of linolenic acid (59.4%) and palmitic acid (10.6%) in the original 3-sn-phosphatidylcholine. Notwithstanding the original 3-sn-phosphatidylcholine contained arachidonic, eicosatrienoic and eicosadienoic acid in comparatively large quantities, the amount of the 3-sn-phosphatidylcholine composed of total carbon number 40 was scarcely, and this showed that the combination of the fatty acids' carbon number among both ester positions in the 3-sn-phosphatidylcholine were not (20+20), but (12+20), (14+20), (16+20) or (18+20).

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The linear relationshi pbetween "apparent jelly strength" (y) of agar gel and agar concentration (x) was investigated for 26 kinds of agar of the various sources. The regression line of y on x was expressed by the followingformula:
y=ax+b
The significances of the coefficient a, the constant b, -b/a, and the estimated error by the regression line were discussed. A practical formula, where the constant b was -50, was also developed for the various possible applications.

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Factors which affected on agar concentration of gels and the related problems were discussed in relation with "apparent Jelly strength". A method to obtain the so-called jelly strength value by calculation which was based on the measured values of the "apparent jelly strength" of the industrial raw gels was introduced.

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