Color deterioration, browning of meat, was observed during soaking in seasoning pickles, so it was aimed to elucidate the mechanism and preventive methods. The deterioration was due to the promotion of autoxidation of heme protein from the oxygenated form to the met form by allicin, a component in garlic. This met formation was 1st order reaction and the half-life was 20min in the case of 4% garlic solution. The power of met formation by 6.25% garlic solution was equivalent to 0.002% potassium ferricyanide or 5% of 2-butanone oxime. The met formation by garlic was depressed by 1% sodium ascorbate. DADS (diallyl disulfide), i. e., allicin decomposition product, has a garlic smell. However, DADS slowly promoted met formation of heme protein and the half-life was 7-12 hours. When garlic was heated, the met formation was depressed by inactivation of alliinase. It was inhibited more when garlic was heated and then cut rather than when it was cut and heated, but the browning couldn't be prevented completely the half-life was 4-5 hours. Though garlic existed, reduced heme protein solution didn't progress to met formation. Reduced heme protein in meat was maintained by means of packaging with an oxygen absorber and thus browning could be prevented. Frozen meat in a deoxygenated package containing oxygen absorber didn't develop browning during storage for one month.

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Infrared spectroscopy has emerged as a powerful technique for the structure analysis of biomolecules in a variety of environments such as aqueous solution, gel or crystals. Fourier transform infrared measurements were applied to examine the structural change of wheat starch in the gelatinization and the retrogradation process. In order to estimate the wavenumber shift and intensity change, second derivative and two dimensional correlation spectra were calculated. Characteristic spectral change were observed in the 1200-700cm^-1 region between the high gelatinized and non-treated starch. Particularly the bands at 1022 and 993cm^-1, which were due to the sugar C-C or C-OH stretching mode, showed the significant intensity change as the degree of gelatinization. These data demonstrated that partial structure change in starch crystals was induced in the gelatinization and the retrogradation process.

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The effect of γ-aminobutyric acid (GABA)-enriched Agaricus blazei (AG-GABA) on blood pressure of mild hypertensive human subjects was studied by an open test and a double blind crossover test. In the open test, the results showed that the average weekly values of all 10 subjects for both the systolic and diastolic blood pressure fell down significantly by AG-GABA intake. In the double blind crossover test, 14 subjects were divided into two groups (group A: 1-4 weeks AG-GABA intake, 6-9 weeks placebo intake; group B: 1-4 weeks placebo intake, 6-9 weeks AG-GABA intake), each consisting of 7 subjects. Each subject in group A or group B ingested 4 capsules per day of AG-GABA or placebo, respectively, in two doses in the morning and the evening for 4 weeks. Then, after 1 week of intermission, group A subjects were changed to placebo capsules and group B subjects to AG-GABA capsules. The blood pressure of each subject was measured daily by the subject himself and by a nurse once a week. Results obtained here both in the open test and the double blind crossover test show that during AG-GABA intake period both systolic and diastolic blood pressure values decreased to statistically significant levels, if compared with those of the pretest period or placebo intake period. No significant difference was observed both in the values of TC, HDL-C, LDL-C, TG, AI, GOT, GPT, γ-GTP, and in blood cell properties during the pre-test period, AG-GABA or placebo intake period, and crossover period. From these results, stated so far, AG-GABA was found to be effective in reducing and controlling blood pressure of mild hypertensive human subjects.

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Near Infrared (NIR) spectra of wheat starch samples having different degree of gelatinization were measured, and the effect of gelatinization on the NIR spectra was examined. NIR spectra were shifted upward/downward depending on degree of gelatinization. Though a baseline shift of the spectra could be removed by second derivative treatment, the changes of spectra due to sample expansion could not be removed. In order to solve this thing, the new spectral normalization technique was developed, which is to divide d²log (1/R) value at each wavelength by d²log (1/R) value at the absorption band due to C-H. The functional group of C-H was not affected by gelatinization. In the normalized second derivative spectra, changes of spectra due to gelatinization could be observed, say, around 1926nm and 2080nm. As a result of multiple linear regression based on the normalized second derivative spectra, a good calibration model could be obtained.

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An ethanol extract (EPE) was prepared from defatted seeds of Evening-primrose (Oenothera biennis L.). In this study, we examined the effect of EPE on postprandial blood glucose level and its active components. Detected polyphenol components of EPE were penta-O-galloyl-β-D-glucose (PGG) 2.7%, gallic acid 3.1%, (+)-catechin 3.4%, procyanidin B1 and procyanidin B3 1.5%. 41.4% of the total proanthocyanidin (PAC) was contained in EPE. Then, we examined the effect of these components of EPE on inhibitory action against α-glucosidase in vitro and on the postprandial blood glucose level using rats. The results suggested that 1) the suppression of postprandial hyperglycemia was caused by inhibition of α-glucosidase activity due to EPE, 2) PAC was the main active component of EPE.

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Mumefural is a component of Japanese apricot fruit juice concentrate, which has been used as a traditional nonofficial medicine in Japan, and was reported to have an activity to improve the blood fluidity. For quantitative analysis of mumefural, water extract of the fruit-juice concentrate was loaded on a cartridge column for solid-phase extraction (Oasis^® HLB, Waters) and eluted with 20% acetonitrile. Following HPLC analysis on a XTerra^TM MS C₁₈ column (Waters) by linear gradient elution with acetonitrile-20mM sodium phosphate buffer (pH 2.3) gave a peak of mumefural at 280nm, from which area quantity of the compound could be elucidated based on the calibration curve obtained in this work. Mumefural content of 4 Japanese apricot fruit-juice concentrates was determined as 1.41mg/g, 0.361mg/g, 11.5mg/g, and 3.82mg/g, respectively, by this method. Accurate molar absorption coefficient (ε) of mumefural was determined as 1.78×10⁴ (λ_max 282nm, water). Since mumefural is highly hygroscopic amorphous solid, it is difficult to weigh out an accurate quantity for preparation of a standard solution. Molar absorption coefficient of mumefural is, therefore, useful to calibrate the concentration of the standard solution for HPLC analysis.

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We examined breaking strength and protein composition for quality evaluation of salmon roe. The protein composition was analyzed by SDS-PAGE. The 47kDa component, which was the main egg membrane protein of salmon roe, was becoming less in low-grade products in which maturation advances. The SDS solubilization rate was 91-99% in extra high-quality products, 87-92% in high-quality product, and 37-76% in low-quality products, respectively. After 72h storage at 5-25°C, the solubilization rate of the egg membrane protein for SDS solution lowered, as the grade of raw material eggs lowered. In addition, there was a difference in the sediment quantity in centrifuged solubilizing liquid, SDS solution added to the egg membrane by homogenization, according to the class of salmon roe. In raw material egg of the C rank salmon which corresponds to a low-quality product, the 47kDa component rapidly decreased after curing. And, the solubilization rate in SDS solution gradually lowered. From the above results, we conclude that the 47kDa component of the egg membrane protein decreases, as the rating of salmon roe drops into lower grades in the three-level grading. In factories where simple measurements are required, sediment quantity and solubilization rate in SDS solution, measured by centrifugal separation, are effective indices which evaluate the rating and quality of salmon roe.

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This paper describes the rapid and easy determination by ultra weak chemiluminescence (CL) method for assessing the degree of autoxidation during storage in several oils, dried fisheries products, and deep-fried snacks. When using luminol and hemoglobin as chemiluminescence reagents, a good correlation co-efficient was obtained between the integral luminescence intensity and peroxide value (PV) of edible oils and oils extracted from above mentioned food products stored for several weeks. Acetone extracts from minced foods were applied to either CL and PV methods. Due to the good correlation with PV method, this simplified CL method could also be useful for evaluation of autoxidation in foods.

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The ethyl acetate extracted fraction of Ume vinegar (AT fraction) contained aryltetralin lignan, lyoniresinol. Lyoniresinol showed various antioxidative activities, such as not only suppressing autooxidation of linoleic acid, but also scavenge of DPPH radical and superoxide anion. Purified lyoniresinol and AT fraction suppressed mutagenesis caused by Trp-P-2 and ethylmethane sulfonate. Lyoniresinol indicated remarkable mutagen scavenging activity, which was based on the antioxidative activity, for Trp-P-2. And the existence of antimutagenetic compounds other than lyoniresinol were also suggested from the result of antimutagenetic activity for ethylmethane sulfonate.

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