The relationship between pulp content and quantitative changes in volatile components during storage was investigated. Juice processed by the In-line Extractor contained about 1ppm of α-tocopherol derived from peel. The α-tocopherol content was constant during 50 days storage at 40°C, but α-tocopherol had no effect on the essential oils from peel in juice. The decrease in d-limonene during storage was proportional to the amount of d-limonene in liquid (serum) fraction, that means the essential oil undergoes a change in serum. The distribution coefficients of major volatile compounds between pulp and serum fraction in juice were determined: terpene hydrocarbons; 60_??_70, linalool; 5.4, citronellal; 3.8, geranyl acetate; 32. Every component is distributed more in pulp than in serum fraction, which is favorable for the preservation of the flavor. In juice with lower pulp content, the formation of α- and β-terpineol and fenchyl alcohol increased with a rapid decrease in terpene hydrocarbons and the flavor deteriorated remarkably. Juice, therefore, may as well contain much pulp for the preservation of the flavor.

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The present study is a continuation of previous work on examining high-boiling fraction constituents.
The high-boiling fraction of China gum terpentine was investigated gas chromatographymass spectrometer. Ten sesquiterpenic hydrocarbons, including α-humulene, 15 sesquiterpenic alcohols and oxocompounds were identified. Two identified components were humulene epoxid-II [18] and 2 (12)-humulen-1-ol [42]. They were obtained from lead tetraacetate oxidation products of α-humulene.
Two sesquiterpenoids were isolated and determined to be caryophylla-4 (12), 8 (13)-dien-3-ol [47] and caryophylla-4, 8 (13)-dien-3β-ol [51] by spectral evidence.

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Ultraviolet spectrophotometry with 2, 2'-Azino-di-(3-ethylbenzothiazoline-6-sulphonic acid) (AB TS), fluorometry with p-hydroxyphenyl acetic acid (HPA) and colourimetry with 4-aminoantipyrine were used for microanalysis of hydrogen peroxide, using test samples of noodles, fish paste and white Shirasu. The ARTS method was successfully applied on noodles and fish paste with a detection limit of 0.5ppm, while it showed low recovery on white Shirasu, indicating that ABTS was degraded by some components in Shirasu. Though the HPA method was successfully applied on noodles and fish paste with a detection limit of 0.2ppm, it was a less reliable than the other two methods. Moreover, measurement was often disturbed by fluorescent substances in foods. The 4-aminoantipyrine method was the most reliable method of the three methods investigated for noodles, fish paste and white Shirasu with a detection limit of 0.2ppm. Recoveries of 4-aminoantipyrine method at 1 or 5ppm levels of hydrogen peroxide on fish paste and white Shirasu were relatively low indicating degradation of added hydrogen peroxide by some heat-labile substances in these foods.

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The juices were adjusted to pH 2.4_??_4.4 respectively and stored for 20 days at 40°C. The off-flavor developed more heavily in the juices of decreased pH. Therefore, the differences in the quantities of volatile components among the juices of various pH were investigated.
The recoveries of terpene hydrocarbons, predominantly d-limonene, were at the maximum level in the juice of pH 3.2_??_3.4, but the recoveries decreased to 60% or less in the juice of lower than pH 2.9 0r higher than pH 3.8.
In fresh aroma components, linalool and citronellal were well preserved in the juice of increased pH.
In off-flavor components, the formations of fenchyl alcohol, β-terpineol and α-terpineol were strongly influenced by pH of the juice and the amounts of these terpene alcohols formed during storage were increased linearly with decrease of pH. Judging from this fact, the reactions of formations of off-flavored terpene alcohols were acid-catalyzed hydration of terpene hydrocarbons. As an exception, effect of pH could not be observed with respect to formation of terpinen-4-ol.
These results lead to the conclusion that the quality of flavor is well preserved in the juice of higher pH.

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A rapid high performance liquid chromatographic method was established for the determination of taurine in drug drinks and beverages. Shodex Ionpak C-811, an adsorption-distribution type column was chosen with combined use of 1% phosphoricacid as the eluant, the eluted taurine being measured by refractive index detector. By use of this condition, it was possible to isolate and estimate taurine from other coexisting substances such as sugars, amino acids and organic acids. Recoveries at lmg/ml spikage level were not less than 86.8%, the detection limit being O.2mg/mt. From the result of actual survey on commercial products, it was revealed that 80% of drug drinks contained O.5_??_1.0% of taurine, and the detected amounts were closely coincident with those labelled. No taurine was detected from commercial beverages.

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The effects of pantethine (PaSS) on the growth of Bifidobacterium were examined. Lactobacillus acidophilus grew on both media containing either Ca-pantothenate (PaA) or PaSS, whereas Bifidobacterium grew only on the latter medium. The essential requirement of PaSS for the growth of Bifidobacterium seems to be explained from the fact that PaSS itself is the precursor of CoA and ACP. Therefore the insufficiency of PaSS has a direct influence on the cell growth. Further research indicated that glucose-6-phosphate dehydrogenase activity in PaSS-deficient cells was 26% of that in PaSS-rich cells. It was concluded that the insufficiency of PaSS was an initial factor for the decrease of the activity of glucose-6-phosphate dehydrogenase, the key enzyme for biosynthesis, and it in turn also resu1ted in the decrease of the cell growth.

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