The characteristics of rice grains cooked with and without lysolecithin were investigated. The results are as follows:
1) The rice grains cooked with lysolecithin were harder and less sticky than rice cooked without lysolectihin. Surface of the rice grain cooked with lysolecithin became smoother than that of grain cooked with a monoglyceride. The change in these properties were significantly correlated with palatability evaluations.
2) The addition of lysolecithin more repressed expansion of rice grain with cooking than monoglyceride addition. However, in this case, expansion ratio of internal part was same to that of external part, comparing with the case of the monoglyceride being different.
3) The amount of lysolecithin penetrated to the internal part was calculated to be 17%, and as the result, concentration of lysolecithin in external part was 3.3 times more than that in the external part.
4) X-ray diffraction and DSC analyses suggested the existence of lysolecithin-starch complex in rice grains cooked with lysolecithin.
5) GPC of the samples with and without DMSO treatment suggested that the ratios of amylose complexed with lysolecithin in the external and internal parts were 3.1% and 2.6% respectively.
6) GPC results indicated about 5% of amylopectin in rice starch being decomposed by lysolecithin in cooking, and this estimation was supported by the model experiment of waxy rice starch with lysolecithin.

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Physical properties of whipping cream were investigated using a cone and plate viscometer. On a viscosity curve of cream measured with the cone and plate viscometer, torque increased linearly with rotational number in the first stage, but the onset of steep increase in torque occurred at a certain rotational number (the second stage). The standardized rotational number of the onset point was defined a-value, and the slope of linear plotting between torque value and rotational number in the second stage was defined as α-value. There was a high correlation between a-value and possible transport distance of creams.Above a-value: 4, viscosity of creams was not increased and a-value was not changed. Under a-value: 4, viscosity of creams increased to more extents during transportation if a-values of the creams were smaller. The possible transport distance was about 300km for a-value: 3-4, about 150km for a-value: 2-3, and under 100km for a-value: <2 respectively. There was not clear relations between a-value and whipping time or overrun. There was a clear relations between α-value and a time-dependent increase of hardness of whipped creams. Larger α-values caused more increases of hardness of whipped creams.

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Because limited researches have been done so far on thawing of frozen foods, it is very important for keeping frozen foods of good quality to estimate food thawing time or changes in temperature profile during thawing period. In view of the fact that food thawing is caused by transition to the aqueous solution in food, we apply unsteady-state heat conduction theory including phase change for analyzing this thawing process. Since in the unsteady-state heat conduction equation the modified thermal diffusivity is related to the temperature, this equation shows intense non-linearity. It is difficult to solve this equation analytically, then we adopt to the collocation method. The calculated results were agreed well with the experimental data obtained from thawing tests of frozen food extracts. It is expected that this result would be useful for frozen food thawing operations.

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It was reported that a simplified synthetic extract of scallop muscle satisfactorily reproduced the taste of the natural extract, and that neither the natural nor the synthetic extract was bitter, despite their having the concentration of Arg approximately 6 times as high as the threshold concentration (50mg/100ml). These results suggest that one or more of extractive components mask the bitterness of Arg. In order to identify the effective component(s), sensory tests were conducted and the following results were obtained. (1) A 0.3% Arg solution was perceived as strongly bitter with weak sweetness. The relative strength of sweetness to bitterness was higher in dilute Arg solutions, 0.15 and 0.075%, than the above concentrated solution. (2) It was confirmed by the omission test employing the synthetic extract that Arg did not impart bitterness to the extract. (3) Glu, adenosine 5'-monophosphate (AMP), Glu + AMP and NaCl were found in addition test to decrease the strength of bitterness due to Arg, with NaCl being the most effective. The effectiveness of NaCl was confirmed in another addition test, in which the panelists could not discriminate NaCl solution from NaCl+Arg solution in terms of bitterness.

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Galanga is widely used as one of the spices throughout southeast Asian countries. The aroma character and some potent odorants of galanga were investigated. The aroma concentrate was prepared by steam distillation under reduced pressure and fractionated into hydrocarbons and oxygenated compounds by silica gel column chromatography. Characteristic aroma was presented in the latter fraction. The constituents were investigated by GC and GC-MS and the potent odorants were determined by combined the GC eluate sniffing and dilution method. By the sensory evalua- tion, galanga soup showed more woody, minty and floral aroma quality than ginger. Sixteen oxygenated compounds were identified and among them 1'-acetoxy chavicol acetate was identified as an aroma constituent of galanga for the first time in this study. It seems that the high proportion of 1, 8-cineol and other phenolic compounds of galanga have a great influence on the difference of the aroma quality from ginger. Five compounds, 1, 8-cineol, linalool, geranyl acetate, eugenol, chavicol acetate were determined as the potent odorants of galanga. In addition, acetic acid, bornyl acetate, citronellyl acetate, 2-acetoxy-1, 8-cineol and the isomer, methyl eugenol and 1'-acetoxy chavicol acetate were also selected as the following important components.

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Changes in chlorophylls, carotenoids, ascorbic acid and glutathione-related compounds were determined during storage of broccoli in modified atmosphere packaging. In non-packaged broccoli, the level of chlorophyl a, b and ascorbic acid significantly decreased during storage, while β-carotene was kept constant. Glutathione gradually decreased after showing 47% increase at the second day of storage. In broccoli packaged with polyethylene, no increase of glutathione level were observed. And glutathione decreased with 28% of the initial concentration during storage for 7 days. Equilibrated concentrations of oxygen and carbon dioxide inside the package of polypropylene was 0.1% and 21%, respectively, and chlorophyl a, b and ascorbic acid were stable for 7 days. However, glutathione substantially decreased and retained only 1.5% of the initial concentration. Storage experiments of broccoli under controlled atmosphere indicated that the substantial decrease of glutathione were due to a low concentration of oxygen but not to a high carbon dioxide. These and other results suggest that presence of oxygen is indispensable for simultaneous maintenance of the pigments, ascorbic acid and glutathione, and its minimum allowable level is ca. 1%.

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Roasted onions with corn oil were prepared. Flavor components of roasted onions of four cultivars grown in Japan: Momiji-3go Taabo, Kitamomiji and Sapporoki, and an unknown cultivar grown in the State of Washington, named "Washington onion", were investigated. The contents of free sugar were analyzed by HPLC. The volatile isolates were obtained by SDE method and analyzed by GC and GC-MS. Momiji-3go cultivated in Awaji area had the highest free sugar contents among 5 cultivars. Momiji-3go was preferable to "Washington onion" for roasted onion flavor in sensory evaluation. Forty five compounds were identified or tentatively identified in roasted onion volatiles. Methyl propenyl trisulfide, diallyl trisulfide, methyl (Z)- and (E)-propenyl disulfides, and furan compounds were the major aroma components of roasted onion, compared with those of boiled onion. Many aliphatic aldehydes existed in roasted onion volatiles. Those volatile aldehydes were thermal generation and oxidation products from corn oil. Those aldehydes were seemed to contribute to the characteristic oily and heavy roasted onion flavor. The similarities among GC patterns obtained from roasted onion volatiles of five cultivars were calculated. The similarities between Japanese onions and "Washington onion" were low. The similarity between Kitamomiji and Sapporoki which were cultivated in Kitami area was very high.

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The influence of several water-soluble organic solvents on the activity of rutin-degrading enzymes (RDEs) I and II of tartary buckwheat (Fagopyrum tataricum Gaertner) seeds was investigated. In the presence of 20% (v/v) water-soluble solvents such as alcohols and DMSO, the RDEs' activity was higher than that observed in the absence of solvent. In the presence of methanol, RDEs had the highest activity. On the effects of concentration of methanol and DMSO, RDEs showed the highest activity in 10-20% (v/v) methanol and 5% (v/v) DMSO. Furthermore stability of RDEs was maintained at the original activity level under this condition. During rutin degradation with RDEs in the presence of methanol, quercetin and an unknown product (X) that was not rutinose were produced. By ¹³C-NMR analysis, we found that the product (X) was methyl β-D-rutinoside.

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Sensory tests were performed to disclose the taste quality of glycine betaine (GB) and its participation in the taste of the muscle of a whelk, Neptunea polycostata, whose GB content was found to be very high, being 1.555g/100g. Results obtained are summarized as follows.
(1) The threshold concentration of GB estimated by the triangle difference test in combination with water was 0.25-0.5g/100ml.
(2) Differing from literatures describing that GB is sweet, more than half and most of panelists perceived bitterness with sweetness for GB solutions of 1.0 and 1.555g/100ml, respectively.
(3) In omission test of GB using a synthetic extract simulating the whelk muscle extract, no significant changes in strength of the five basic tastes were perceived by the panel. Furthermore, the addition of GB to a GB-deficient synthetic extract did not enhance the strength of sweetness. However, it was increased significantly by the addition of GB to the synthetic extract devoid of GB and sweet amino acids, indicating that the contribution of GB to the sweetness of seafoods is not so high as so far evaluated.
(4) It was suggested by the panel that GB intensifies thickness, fullness and aftertaste of the synthetic extract.

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Antioxidative compounds were isolated from ethanol extract of Saxifraga stolonifera MERB. and their activity were determined. They were identified as quercetin, chlorogenic acid and bergenin. Consequently, antioxidative activity of S. stolonifera was considered to be due to co-operation of many polyphenol compounds.

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Although the ascorbic acid (AsA) content in most vegetables is decreased by wounding, that in potato tubers tends to be increased by wounding.The change of AsA content in wounded potatoes was investigated in connection with the Storage time after harvest to clarify the cause of the AsA increase. Whereas the AsA content in wounded potato tubers did not increased within 4 weeks after harvest, the content slightly increased during 5-6 weeks and remarkably increased after 7 weeks. The AsA content in potato tubers stored more than 7 weeks after harvest decreased to approximately half the value on the beginning of storage, but it returned to the original value by wounding. The activity of L-galactono-γ-lactone dehydrogenase, the synthetic enzyme of AsA, in wounded potato tubers also was remarkably increased by using tubers stored more than 7 weeks. These results suggested that potato tubers wounded after a constant storage time increase the AsA content to overcome the damage generated by wounding stress.

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The carotenoid contents in F₁ and F₂ plants of Beta orange strain and Delta strain were investigated. The interaction of gene B and Del on the carotenoid biosynthesis was also investigated. In F₁ hybrid, the content of α-carotene specifically increased as compared with their parent strain, while the content of ε-carotene slightly increased, F₂ plants were consisted of 9 types. These types were divided into 3 subgroups. Group 1 (4 types) contained so much amount of α-carotene, while group 2 (2 types) contained little amount of α-carotene. Group 3 (3 types) contained no α- and δ-carotene. ε-carotene was detected only in the plants contained α-carotene. These results suggest that genes B and Del highly and complementally participate in the biosynthesis of α-carotene, and that gene Del mainly participate in the biosynthesis of carotene with the preceding participation of gene B. Namely, gene B participates in the cyclic formation of β-ionone, and there was a mutual relation of BB>B⁺B>B⁺B⁺ in β-carotene productivity. Gene Del participates in the cyclic formation of ε-ionone, and there is a mutual δ-carotene productivity is in a relation of DelDel>Del<⁺Del, but none in Del⁺Del⁺. Gene B and gene Del participate in production of α- and ε-carotene, and ε-carotene productivity was most remarkable in BBDelDel, less in B⁺BDel⁺Del, scarce in B⁺B⁺DelDel. But in B⁺B⁺Del⁺Del⁺, ε-carotene was not formed.

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