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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.

Six morphinane alkaloids, cephasamine (3), cephakicine (4), tannagine (6), 14-episinomenine (7), FK-3000 (8), and sinoacutine (9), and five hasubanane alkaloids, cephatonine (5), cepharamine (10), aknadinine (11), aknadicine (12), and aknadilactam (13), were isolated from the tuber of Stephania cepharantha Hayata (Menispermaceae) cultivated in Japan. Three of these (3−5) were new alkaloids. Structures were spectroscopically determined by comparison of their 1H and 13C NMR data with that of cephamonine (1), cephamuline (2), and other known alkaloids (6−13).

An improved method of urea detection having a sensitivity to 0.05 ppm, applicable to white wines, was developed by modifying Jansen's procedure. The urea concentration in many commercial bottled wines was found to be around 2 ppm. The method was utilized to the urea degradation by an acid urease which degraded naturally occurring urea of OS-2 ppm at the same reaction rate as that for the spiked urea of 30 ppm in the same white wine. Wine treatment with the acid urease also reduced ethyl carbamate formed by heating.

Gel formation of curdlan at lOO-130°C and behaviors of curdlan gels under frozen state were investigated by measuring gel strength and syneresis. Even when aqueous suspensions of curdlan were heated to 100°C or higher, they formed a gel, and gel strength increased with temperature. Curdlan gel was also stable against freezing and thawing. The syneresis of a 4% curdlan gel after freezing and thawing was reduced from 20.6% to about 2.1% by addition of 5% waxy corn starch and to 8.9% by addition of 20% sucrose. Suggested by these findings, new applications to foods have been developed, especially those subject to retorting and/or freezing.

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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

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