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Both whipping and emulsifying properties, the characteristic functional properties of soybean products, were investigated by using the commercial products in Japan. Whipping properties of the soybean products, expressed by foam expansion and foam stability, were found to correlate with water dispersible nitrogen, and the resultant foams were stable when the dissolved proteins were native. Thus, the native defatted soybean flour which contained native and soluble protein exhibited excellent whipping property. Emulsifying properties correlated positively with protein and negatively with fiber contents. As soybean protein isolate and soybean protein extract are rich in protein and poor in fiber contents, both of them show good emulsifying functions.

Fatty acid composition of lipids from polished rice was studied by gas chromatography on the separated fractions, fat-by-hydrolysis, neutral fat, free fatty acid and phospholipid. After six months storage, fatty acids were released from neutral fat in the same proportion as they were combined in the neutral fat.

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Taste interactions of /?-cyclodextrin with naringin or limonin, which are bitter tasting constituents of citrus fruits and their products, were evaluated by psychophysical methods. The mechanism of interaction of /?-cyclodextrin with naringin or limonin was explained by both the solubilities of the bitter tasting compoundsand the changes brought about by proton shifts within the jS-cyclodextrin. In the presence of 0.5% j5-cyclodextrin, the bitterness of naringin or limonin was reduced to approximately half of what it was without jS-cyclodextrin. This reduction in bitterness by /?cyclodextrin was also observed in the citrus juice itself. The solubilities of naringin or limonin increased with the addition of /?-cyclodextrin. In a series of XHNMRspectra of j5-cyclodextrin in D2O, the low-field triplet signals assigned to the H-3 and H-5 protons, which are located within the cavity of /?-cyclodextrin, showed a gradual shift to the higher-field values with increases in the molar ratio of naringin to jS-cyclodextrin. It was concluded that this bitterness reduction was due to the formation of an inclusion complex between the /?cyclodextrin and the naringin or limonin. The bitterness of citrus fruits and their products is caused primarily by either of two constituents-naringin and limonin. Naringin is said to be the bitter tasting constituent of grapefruit, natsudaidai, buntan oranges and so forth.1} On the other hand, limonin is the bitter tasting component of navel oranges, Valencia oranges and iyo oranges, among others.2'3) These bitter compounds are often necessary components for the acceptable flavors of citrus juices. However, when the intensity of the