This study was conducted in order to reveal the weak luminescence phenomena, such as spontaneous ultra-weak photon emission, chemiluminescence and Photo-Stimulated Luminescence (PSL), in food materials. Additionally, new food-quality evaluation methods using weak luminescence were developed as screening methods. Spontaneous ultra weak photoemission from potato chips, rice grain and roasted sesame oil were measured using photon counting and imaging techniques. Ultra weak photon emissions from the food materials were related to quality changes. Chemiluminescent reagents have advantages in improving emission levels and enabling functional selectivity, such as toward reactive oxygen species, antioxidants and so on. Sake quality and buck wheat antioxidative property could analyze using chemiluminescence. The PSL method provides a rapid and remarkably sensitive technique for identifying irradiated foods that contain minerals, such as spices and dried vegetables. A novel PSL method that detects irradiated foods, based on time-dependent intensity decline, was developed. These weak luminescence techniques might use in quality analysis for food processing and distribution.

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The purpose of this study was to investigate the effects of mechanical properties of foods on tongue movement at initiation of swallowing. Five healthy adult volunteers freely ate four types of food (3ml of hard gel, soft gel, sol and liquid). A probe was placed under the chin and the coronal section of the tongue was observed. Displacement of the dorsal surface of the tongue from the under surface of the chin was recorded against time using M-mode ultrasound imaging. We analyzed up-down movement of the tongue with the grooving depth, and the velocities of descending and ascending of grooving. The results obtained were as follows. 1) The grooving depth differed significantly among the foods; the sol showed the maximum and water exhibited the minimum. 2) Mechanical properties significantly affected the velocity of descending grooving, which was greatest for the sol. 3) The velocity of descending grooving was greater than that of ascending grooving for all the food samples. The results suggested that tongue movement at the initiation of swallowing changes according to the mechanical properties of foods.

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Anthocyanin is unstable and mainly degraded by oxidation and heating processes in liquid during beverage production. Although several efforts to stabilize blackcurrant beverages have been made, adequate results have yet to be achieved. In this study, we examined whether CO₂ microbubbles could reduce O₂ concentration and improve the stability of anthocyanin, which is one of the most important components in blackcurrant beverages. Microbubbles have relatively large surface areas and high mass transfer rates. Therefore, this study focused on their high rate of gas dissolution in liquids. Using CO₂ as a supply gas, a pressurized dissolution method microbubble generator introduced microbubbles with a mode diameter of 64μm into a blackcurrant beverage. The O₂ concentration rapidly decreased to levels below the detection limit (<0.1mg/L) after 45 min, as compared to 270 min with the common bubbling treatment (3mg/L). The beverages were bottled, stored for 28 days at 37°C and then analyzed for anthocyanin content. The anthocyanin content was significantly higher in the beverages containing CO₂ microbubbles than in both the beverages prepared using the common bubbling method and the untreated controls. These results suggest that introducing CO₂ microbubbles into blackcurrant beverages effectively improves anthocyanin stability.

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A semi-quantitative competitive PCR method for estimating rice flour content in rice bread was developed. PCR primers were designed using sequences common to the rice and wheat chloroplast genomes and their resulting amplicons were distinguished and quantified by gel electrophoresis. Competitive PCR analysis using different DNA sources, amounts template DNA, and PCR cycles showed that the ratio of amplicons was little affected by PCR conditions, and was approximately proportional to rice flour content in rice bread, ranging between 0 and 50%. On the other hand, the amplicon ratio was affected by material rice cultivars and possibly by bread type.

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It has been observed that recent unusual weather changes have caused major variability in the quality of rice grain, which is the main ingredient in rice crackers. This study clarifies the physicochemical properties of chalky rice grains in relation to rice cracker processing and quality. We aimed to establish a useful assessment method. Both quality and physicochemical properties were analyzed in rice crackers containing 0%, 50% and 100% chalky rice grains. Chalky rice grains exhibited low rates of amylose and starch degradation, and high levels of protein content and α-amylase activity. Protein content and α-amylase activity had a high negative correlation, while amylose and starch degradation rates had a high positive correlation in sensory evaluation. Whereas conventional techniques evaluated amylose rate and performed multiple regression analysis of multicollinearity, we created a new evaluation system using both amylose rate and α-amylase activity as explanatory variables. A higher coefficient of determination was seen with this new evaluation system, which suggests that rice cracker quality can be predicted based on mixtures of chalky rice grains.

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We have developed an analytical method for mucopolysaccharides (MSs) and a simple method for removing their impurities from un-fractionated heparin (UFH) preparations. An over-sulfated chondroitin sulfate standard (OSCS-STD) was de-polymerized with nitrous acid, as were UFH sodium salt containing OSCS and other MSs (OSHP-SH), OSCS reference standards containing heparin (CSMS-CE1 and CSMS-CE2), and various UFH products. Following de-polymerization, the molecular weight distributions of these samples were analyzed by gel permeation HPLC. The molecular weight distribution of OSCS-STD remained unchanged before and after nitrous acid de-polymerization, and the molecular weight distribution of OSCS-STD was similar to that of OSHP-SH de-polymerized with nitrous acid. On the other hand, the molecular weight distributions of CSMS-CE1 and CSMS-CE2 were similar to that of standard chondroitin sulfate B. UFH sodium salt and several drug substances containing heparin and other MSs were then purified by ethanol precipitation. After nitrous acid de-polymerization, gel permeation HPLC and ¹H-NMR spectroscopy revealed that MSs resistant to de-polymerization with nitrous acid were concentrated in the supernatant and heparin was concentrated in the colloidal precipitate.

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Carnitines exist as either free carnitine or acylcarnitine bound to a fatty acid. However, most of the acylated forms are found only in minuscule amounts, and thus not easy to separate, detect and quantify. Therefore, the purpose of the present study was to determine the quantity of free carnitine and acylcarnitine in venison (round primal cut) using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Free carnitine and four acylcarnitines (acetylcarnitine, hexanoylcarnitine, myristoylcarnitine and palmitoylcarnitine) were detected. These results suggest that venison contains more free carnitine and acylcarnitines than beef, pork and chicken.

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