Fucoxanthin in brown algae, such as Wakame, Kombu and Mozuki, is an oxygen-containing carotenoid xanthophyll and is highly bioavailable. Dietary fucoxanthin is found in the blood after being processed to fucoxanthinol by deacetylating hydrolysis in the intestinal epithelial cells. The pharmaceutical parameters in human subjects of a single dose of 47 μmol fucoxanthin are C_max, 44.2 nmol/L; T_max, 4 h; t_1/2, 7.0 h;and AUC_∞, 664 nmol/Lxh. Most of fucoxanthinol is excreted in urine at around 25 h after ingestion and produces no side effects. Even with such short-term residence time in the blood, fucoxanthinol exhibits diverse and significant biofunctions, such as cancer preventing action, anti-obesity effect, improvement of lipid metabolism, and antioxidant potency. In this review, the bioavailability and diverse biofunctions of dietary fucoxanthin will be described.

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The amount of freezable water in starch had been estimated assuming that the heat of fusion is identical for both freezable and free water. Based on the hypothesis that freezable water contains both free and bound water, and that there is likely to be a difference in their heats of fusion, differential scanning calorimetry (DSC) was performed across the temperature range of −30-120°C on potato and nonglutinous rice starch with a wide range of water contents. The analysis results suggested that freezable water contains free water and bound water that demonstrate different fusion behaviours, and that the ratio of free to bound water changes depending on the water content. Bound water has a heat of fusion of 225-246 J/g water, which is two-thirds that of free water. For high water content, the fusion of free water as well as the existence of bound water for raw starch at 0.09-0.10 g water/g dry matter (gW/gDM) and gelatinized starch at 0.18-0.23 gW/gDM were confirmed. Using the calculated value of the heat of fusion of bound water, 0.30-0.40 gW/gDM of unfreezable water was estimated in the measured samples.

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Conjugated linoleic acid (CLA) comprises geometrical and positional isomers of linoleic acid and is a fatty acid with a conjugated double bond. The activities of CLA, including anti-obesity and anti-cancer activities, are known, and CLA is now used as a health-food supplement for its beneficial effects. However, there are few reported studies on CLA intake, absorption and metabolism in the Japanese population. Information about CLA intake in Japanese individuals was obtained in the present study by examining the daily intake of CLA, normal blood CLA levels, and the change in blood CLA levels after taking a CLA supplement. Results indicate that the normal dietary intake of CLA for Japanese individuals is 37.5 mg/day. Normal blood CLA levels are 6.4 μmol/L in plasma and 1.7 μmol/L in red blood cells. After taking 2.3 g/day of a CLA supplement for three weeks, blood CLA levels were 7.7-fold higher in plasma and 8.7-fold higher in red blood cells. Although normal dietary intake and blood levels of CLA in Japanese individuals were lower than those in non-Japanese subjects reported in previous studies, Japanese individuals taking a dietary supplement of CLA showed a dramatic increase in blood CLA levels. Therefore, long-term intake of 2.3 g CLA/day as a dietary supplement likely has a positive effect in Japanese individuals.

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We determined the stable carbon and oxygen isotope compositions (δ13C and δ18O) of apples grown at various locations in Aomori Prefecture, Japan and China. The values could be used to distinguish the geographical origin. The δ13C and δ18O values for Aomori apples were significantly smaller than those for Chinese apples. Moreover, among eight locations within Aomori Prefecture, δ18O values of apples from Nishimeya and Oowani were relatively lower than those from the other six locations, and the δ13C values of apples from Nishimeya were relatively lower than those from the other seven locations. These results are consistent with previous findings that δ13C and δ18O values of plant tissues, such as fruits, reflect the environment in which the plants are grown (e.g., low δ18O values were found for Nishimeya and Oowani, which have large amounts of precipitation). Thus, δ13C and δ18O values are potentially useful for the discrimination of geographical origin of apples between Japan and China and for apples produced within Japan.

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Volatile compounds from a chilled grape-flavored black tea beverage (grape tea) permeating through gable-top non-barrier and barrier cartons were analyzed by gas chromatography/mass spectrometry (GC/MS) and GC/olfactometry (GC/O). We first developed a new glass apparatus to capture volatile compounds permeating through packaging materials of gable-top cartons. Using this apparatus, the sampling conditions for volatile compounds from grape tea permeating through the non-barrier and barrier materials were determined as follows: SPME fiber, PDMS/DVB; sampling temperature, 10°C; duration of SPME exposure, 30 min; sampling timing for SPME exposure, after 24-hr incubation at 10°C. Under the conditions, volatile compounds from grape tea permeating through the non-barrier and barrier materials were captured by the SPME fibers, and analyzed by GC/MS. The GC/MS results showed remarkable differences in the peak areas of ester compounds depending on the packaging materials. In addition, GC/O analyses revealed that odor intensities (charm values) of the following six odorants: ethyl 2-methylpropanoate, ethyl butanoate, ethyl 2-methylbutanoate, ethyl 3-methylbutanoate, ethyl 2-methylpentanoate, and methyl anthranilate, were significantly higher when packed in the non-barrier material than when packed in the barrier material. These results will provide useful information for development of formulas and selection of packaging materials suitable for gable-top carton beverages.

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The effects of measurement and preparation conditions on the mechanical properties of so-called konjac jellies were investigated using agar jellies for comparison. Here, konjac jellies represent dessert jellies containing konjac-based materials as a constituent with other polysaccharides like κ-carrageenan and locust bean gum, whereas agar jellies contain only agar as a polysaccharide source. As mechanical properties, the apparent breaking stress and strain were determined by puncture tests. Both fracture parameters for konjac jellies were more sensitive to the measurement conditions, including size of the plunger relative to the container, table speed (deformation rate), trigger settings, and temperature than those for agar jellies. Moreover, these fracture parameters for konjac jellies were more sensitive to the preparation conditions, including swelling time of konjac mannan (as a constituent) and storage time of jellies, than those for agar jellies. These results indicate that more detailed conditions should be required for determination of the mechanical properties of konjac jellies when the test protocol is standardized or manualized in terms of data reproducibility and universality.

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To investigate the effects of bite speed on the basic parameters in texture profile analysis (TPA), three different samples were measured using four commercial instruments. The 2-bite TPA tests, where the plunger changes direction twice, downward and upward to a food sample, were conducted at test speeds of 10 mm/s and 1 mm/s, and values of maximum stress, tensile work and second-to-first bite work ratio were compared among the instruments. Significant differences among the four instruments were found in the textural parameters measured at 10 mm/s but not at 1 mm/s. Under the 10 mm/s condition, two of the instruments could not correctly change the movement direction at a set compression distance. Another instrument needed a significantly long acceleration period, which influenced the work values. Some instruments detected noise due to inertia that significantly affected the textural parameters. These data obtained from different commercial instruments at 10 mm/s indicated it is difficult to interchange these instruments with each other.

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Anthocyanins in black pearl rice and soybean were extracted using the optimal solvent, trifluoroacetic acid:water:methanol=0.5 : 60 : 40. Total anthocyanin in these extracts was quantified using the pH differential method and high-performance liquid chromatography (HPLC) . The results from the two methods showed a high correlation, and the pH differential method is a simple spectral method showing good reproducibility of total anthocyanin content in these grains. The total anthocyanin content in black pearl rice (mean±S.D., 742.9±572.7 μg/g; n=16) showed a broader distribution than did that for black pearl soybean (968.9±270.1 μg/g; n=20) . HPLC analysis showed that the major anthocyanin in black pearl rice and soybean was cyanidin-3-glucoside. The proportion of cyanidin-3-glucoside in the total anthocyanins in black pearl rice was almost constant (96.1±1.1%; n=16), while that in black pearl soybean showed a wide range (64.6-100.0%).

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