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The stability of wheat bran proteases for producing angiotensin I-converting enzyme (ACE) inhibitory peptides during storage was investigated. The aspartic proteinase activity upon storage at 15, 20, and 30°C was > 90% of initial levels after 30 days, while storage at 40 and 50°C resulted in levels of 87.3 and 63.1%, respectively. The carboxypeptidase activity remained constant at all temperatures during the storage period. The yields of ACE inhibitory peptides from wheat bran at 15, 20, 30, 40, and 50°C after 30 days were 99.0, 98.0, 97.1, 97.1, and 92.2% of the initial level, respectively. The ACE inhibitory activity of all fractions was > 95% of the initial level. These results indicated that the storage of wheat bran at 15 to 40°C results in maintenance of the ACE inhibitory peptide-producing activity, for at least 30 days.

The content of insoluble bound phenolic acids in pearled barley was determined by an analytical system consisting of alkaline hydrolysis extraction, high-performance liquid chromatographic separation and electrochemical detection. Insoluble bound phenolic acids in five pearled cultivars and fifteen breeding lines of barley comprised ferulic acid (4.3-34.2mg/100 g dry matter), sinapic acid (0.025-0.445 mg/100 g), caffeic acid(0.002-0.016 mg/100 g). Soluble free polyphenols comprised procyanidins(12.2-80.3 mg/100 g), catechin (0.1-28.2 mg/100 g), and total pholyphenolcomprised 152.4-324.0 mg-gallic acid equivalents/100 g. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity for the barley samples ranged from 403 to 1501 μmol-Trolox equivalents/100 g whereas those of oxygen radical absorbance capacity (ORAC) ranged from 1050 to 3816 μmol-Trolox equivalents/100 g. High correlation (0.980, p

The content of synephrine, an adrenergic phenethylamine, was determined by high performance liquid chromatography (HPLC) in Shiikuwasha (Citrus depressa, Hayata) plant material (flesh and peel) during fruit development, as well as in 45 species and cultivars of Citrus genus. HPLC conditions were as follows: column, Develosil ODS-5; mobile phase, acetonitrile-H2O (2:98)-10 mM phosphoric acid and flow rate, 0.8 mL/min. In the extraction of synephrine from the sample citrus peel, a large quantity of synephrine was detected in water (100%) while no synephrine was found in the methanol extract (more than 60% concentration of methanol). Synephrine content in the peels during Shiikuwasha fruit development was gradually decreased to half the amount in January compared with that in August. Synephrine was detected in 30 of the 45 species and cultivars of Citrus genus, and was mainly found in the samples of Aurantium and Acrumen sections according to Tanaka's classification.

Certain qualitative properties of Citrus depressa juice extracted by belt-press, centrifugal, and screw-press extractors were investigated to evaluate the methods for extracting Citrus depressa juice currently used in Japan. Among the three methods, juice yield was highest with screw-pressing. The migration rate of polymethoxyflavonoids (PMF) to the juice was also highest with screw-pressing. Screw-pressed juice had different physicochemical properties from the other two types of juices, and it was evaluated as being unsuitable for drinking following a sensory test. Citrus depressa juice processed by belt-press and centrifugal extractors had lower juice yield and a lower migration rate of PMF. Citrus depressa juice processed by centrifugal extractors was evaluated by a sensory test as being the best of the three types of juices for drinking. PMF and vitamin C found in Citrus depressa juice were largely retained during filtering, sterilizing, and bottling after being extracted with these three methods.

A micellar electrokinetic capillary chromatographic (MEKC) method was developed for the two major polymethoxylated flavones, nobiletin and tangeretin, using a fused-silica open-tubular capillary in a 70% methanol extract from citrus albedo tissue. A MEKC separation buffer (pH 7.0), consisting of 32mM sodium dodecyl sulphate (SDS), 20mM sodium dihydrogen phosopate, 12mM disodium tetraborate and 20% methanol, was selected in order to optimize separation conditions. The order of elution was nobiletin and tangeretin. Of the 46 species and cultivars in the Citrus genus, 17 were assayed for nobiletin and/or tangeretin in this study. The Acrumen and Pseudofortunella sections, classified by Tanaka, were found to contain the highest flavone concentrations.

The relationship between ingestion of coffee and reduction of mental stress was investigated in 256 young Japanese women. Among the 68% of subjects whose questionnaire responses indicated that they liked coffee, 68% indicated they feel relaxed when they drink coffee. In an organoleptic test, coffee extracted at 80°C exhibited a greater relaxation effect than coffee extracted at 65 or 95°C. This effect showed a significant negative relationship to sourness, suggesting that the relative lack of sourness enhances feelings of relaxation. Coffee drinking also decreased experimentally-induced mental stress evaluated by chromogranin A concentrations.

Essential oils of citrus fruits have many uses in consumer products so that efficient methods for their isolation are needed. Membranes are often used in the separation process but a common problem is that the flux through the membranes decreases with time. In the present study we examined whether ceramic membranes might be better at maintaining the flux at acceptable levels. To test the membranes, we attempted differential recovery of nonpolar terpene hydrocarbons and aqueous oxygenated compounds from condensates produced as a by-product during the concentration of citrus juices. When zirconia membranes (ZrO2-UF, cut-off molecular weight 50,000 and ZrO2-MF, pore size 0.08 μm) were used, little decrease in the flux was observed during filtration. The nonpolar terpene hydrocarbons were retained while more polar oxygenated flavor compounds passed through the membrane. The percentages of alcohols, esters, and aldehydes in the permeate increased markedly compared with their percentages before filtration. When the condensate from the concentration process of citrus juice sampled from a juice factory was filtered using ZrO2-UF, the hydrocarbons was concentrated, and a water-soluble essence consisting primarily of oxygenated compounds was obtained in the permeate.

To determine a useful method for evaluating the quality of fresh-cut Welsh onions (Allium fistulosum L.), the onions were examined and electrical conductivity (EC), potassium and ammonia contents of electrolyte solution extracted from them were compared. The quality of cut onions stored at 0, 5 and 10°C was stable for 6 days, while the quality of those stored at 15 or 20°C showed slight deterioration after 4 and 3 days of storage, respectively, with mashed deterioration occurring thereafter. EC of onions stored at 15 or 20°C decreased for the first 4 and 3 days of storage, respectively, and thereafter began to increase, although that of onions stored at 0, 5 or 10°C decreased throughout the storage period. The changes in potassium content extracted by homogenization were steady during storage, although the changes in potassium extracted by leakage were similar to those in EC stored at 15 or 20°C. The relationships between EC or potassium content and quality of cut onions suggested that electrolyte leakage occurred when the tissue collapsed due to decay. In cut onions stored at 15 or 20°C, ammonia was first detected after 4 or 3 days, respectively, with high levels of ammonia detected thereafter. This indicated that ammonia is formed in the cellular tissue. The first day on which ammonia was detected corresponded approximately with the day on which an unpleasant odor was detected. Chlorophyll content of cut onions decreased with decay. However, in the case of EC, potassium and chlorophyll, the quality of the onions could not be known without continuous measurement. On the contrary, if ammonia was measured once, the quality of the onions could be evaluated; therefore, ammonia was a good parameter with which to evaluate onion decay.

A theoretical model of the atmosphere within polymeric film and shipping containers was developed and validated by experiments with or without Welsh onion (Allium fistulosum L.). There were three processes in the model: respiration of fresh vegetables, permeability of gas in polymeric film and permeability of gas in the shipping container. The respiration rate of Welsh onion was expressed in a multiple regression equation. When empty packages were used, changes in carbon dioxide (CO2) and oxygen (O2) concentrations inside the unperforated polypropylene (OPP) film packaging and expanded polystyrene (EPS) containers agreed very well with the simulated data. These results indicate the suitability of the proposed model. Changes in CO2 and O2 concentrations in the EPS container were approximated when Welsh onion was placed in the film package. The predicted CO2 and O2 concentrations in the OPP film differed slightly from the experimental data obtained with a maximum of 1.5% and 1.2%, respectively, but gas correlated significantly with the model. Therefore, the simulation model may be useful for fresh vegetables wrapped with polymeric film and then encased in shipping containers.

The chemical components and quality stability of pre-cut Welsh onion wrapped in an unperforated or micro-perforated orientated polypropylene (OPP) film package were evaluated during storage at 10°C. The concentration of oxygen (O2) in the unperforated OPP package decreased rapidly to 2% while that of carbon dioxide (CO2) increased. Therefore, the onion underwent anaerobic respiration, ethyl alcohol was produced and some of the chemical components were lost. Moreover the cellular tissue of the vegetable became water-soaked. The O2 concentration in the OPP film package with too many micro-perforations decreased slightly, so that ethyl alcohol was not detected but there was a loss of chemical components. The quality of the product was diminished and the onion was unmarketable after 6 days of storage. For cut Welsh onion packed in perforated OPP film (with 24 micro-perforations), the O2 concentration in the package was not as low as in the modified atmosphere packaging for onion, but did decrease to 10%. Ethyl alcohol could not be detected and there was no or only slight loss of chemical components, so that the onion was still marketable after 6 days of storage.

Chemical components and quality of Welsh onion (Allium fistulosum L.) wrapped roughly or completely heat-sealed with orientated polypropylene (OPP) film were investigated during storage at 5 and 20°C. Concentrations of oxygen (O2) and carbon dioxide (CO2) in the roughly heat-sealed packages were the same as in air, whereas O2 concentration in the completely heat-sealed packages decreased to 2-3% at 20°C and to 4-5% at 5°C. Contents of reduced ascorbic acid (RAA) and chlorophyll in onion which was roughly sealed and stored at 20°C decreased, and withering of leaf tip occurred. This meant that the quality deteriorated severely. However, the contents of RAA and chlorophyll in Welsh onions which were sealed completely and stored at 20°C, and which were sealed roughly or completely and stored at 5°C, did not change or only slightly decreased. In Welsh onion sealed completely and stored at 20°C, off-odor was detected after 2 days and severely after 7 days and leaf tips began to wither after 7 days, suggesting that quality could be kept only for 4 days storage. In Welsh onion sealed completely and stored at 5°C, off-odors and withering of leaf tip was not observed for 9 days, indicating that quality marketability could be kept for that period.

Iyo tangor (Citrus iyo hort. ex Tanaka) seeds contained limonin, nomilin, obacunone and deacetylnomilin, in order of decreasing concentration. They also contained the 17-β-D-glucopyranosides of nomilin, obacunone, limonin, deacetynomilin and nomilinic acid. Total limonoid aglycone concentration in the seeds was 873 mg per 100 g on a dry weight basis and total limonoid glucoside concentration was 446 mg. The composition and relative concentration of each limonoid aglycone and glucoside in Iyo tangor seeds were very similar to those of other citrus species distributed widely in western Japan such as Valencia orange (C. sinensis Osbeck), Sanbokan (C. sulcata hort. ex Tanaka) and Hyuganatsu (C. tamurana hort. ex Tanaka). These data reveal that Iyo tangor taxonomically belongs to the same group as those citrus species.