A simple and rapid method has been developed for determining 4 sweeteners of acesulfame potassium (AK), sodium saccharin (SA), aspartame (APM), neotame (NE) and 2 degradation products of diketopiperazine (DKP) and dimethylbutyl-aspartyl phenylalanin (DMB-AP) in various foods by high performance liquid chromatography (HPLC). These compounds in foods were extracted in ultrasonic bath, and the extract was loaded onto a strata-X-C, cation-exchange and reverse-phase cartridge. The HPLC separation was performed on a Inertsil ODS-4 column (5 μm, 4.6 mm i.d. × 150 mm) using 0.01 mol/L phosphate buffer (pH3.5) and methanol as a mobile phase. The injection volume, flow rate and column temperature were 10 μL, 1.0 mL/min and 40℃, respectively. A UV absorbance detector was set to 210 nm. The recoveries of 4 sweeteners and 2 degradation products from foods added at the level 0.20 g/kg and 0.04 g/kg in HPLC were 82.3-104.9% and 80.4-108.1%, respectively. The determination limit of these compounds was 0.005 g/kg. Nine commercial foods indicated the using of NE were determined by the proposed method. NE was detected in 6 foods in the range of 0.02-0.09 g/kg, AK and APM were detected in 2 foods, simultaneously.

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Polyethylene terephthalate (PET) bottle is widely used for food packaging. The ratio of PET bottle in the beverage packages is as much as 64.9%, so we should develop sustainable PET bottles from the viewpoint of environmental impact reduction. In this study, we estimated the cleaning efficiency of mechanical recycle system of commercial plant, and the direct food contact impact in the application of mechanical recycled PET bottles in accordance with the FDA guidance. The contaminated PET flakes were prepared artificially with eight surrogate contaminants, namely N-methylpyrrolidone, 2-(2-bufhoxyethoxy)ethanol, diethylketone, toluene, benzophenone, naphthalene, phenylcyclohexane, and decane, in the level from 44 to 23000 mg/kg. The contaminated flakes were added by the ratio of 1% to non-contaminated flakes, and they were processed in the real plant of mechanical recycle. As a result, the cleaning efficiency throughout all processes was from 95.1 to 99.8%. And in the analysis of relationship between the cleaning efficiency and the physical properties of contaminants, we determined good regression equations in alkaline washing and vacuum melt extrusion. Additionally migration test was carried out by using beverage or liquor simulant stored for three months in the bottles manufactured from the resin processed in the prior test. As a result, any surrogates were not detected, and it satisfied the FDA's migration limit of 10μg/L.

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Changes in sarcoplasmic proteins during the burnt meat occurrence of cultured yellowtail were investigated using SDS-polyacrylamide gel electrophoresis (SDS-PAGE) and 2D-gel electrophoresis. The decreased proteins during burnt meat occurrence were identified as muscle glycogen phosphorylase (PYGM), phosphoglycerate kinase (PGK), creatine kinase (CK), glyceraldehydes-3-phosphate dehydrogenase (GAPDH), L-lactate dehydrogenase (LDH) and adenylate kinase, respectively, by MALDI-QIT-TOF mass spectrometry (MALDI-QIT-TOFMS). The decreases of sarcoplasmic proteins were little suppressed by the protease inhibitors in vitro. In contrast, some sarcoplasmic proteins such as PYGM, GAPDH and aldolase were appeared in myofibril fraction of burnt meat. These results suggested that the sarcoplasmic proteins are insolubilized and shifted to myofibrillar fraction, when the burnt meat occurs in cultured yellowtail.

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In April 2008, the polysorbates emulsifiers (PSs) were approved as food additives, thereafter it has been increasingly used in Japan. The analytical method in foods was notified by the Ministry Health, Labour and Welfare. In the official method, PSs were extracted from processed foods with the mixture of acetonitrile-methanol-n-hexane and the extract was cleaned up on an alumina column and a silica gel cartridge to remove food color and other interfering substances. In such a complicated process, including salting-out and liquid-liquid partition, this method often showed poor recovery of PSs. To simplify operations and improve purification process and recovery rates, we have examined commercially available column cartridges: a silica gel, a diol, an Ag-ion, an alumina-B, and a graphitized carbon black column cartridges. In this paper, we propose an effective new method for analysis of PSs. A new method uses ethyl acetate containing 10% methanol for extraction of PSs, and a diol cartridge (MEGA Bond Elut-Diol) and an Alumina-B cartridge (Sep-Pak Plus Alumina B) for removal of fat and food color. The presence and the content of PSs are determined by TLC and colorimetric assay, respectively. Using a new method, the recoveries of PS80 in foods fortified at the levels 0.05-5 g/kg ranged from 47 to 89%. The limit of quantitation for PS80 in foods was 0.05 g/kg.

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Recently, it has been recognized effectiveness and functionality of aromatherapy, a natural holistic approach to therapy using essential oils and other plant extracts. Many common essential oils have been used for such as perfume materials, flavor ingredients and antiseptic purposes since ancient times and are still widely used today. Essential oils are registered in "The Japan's Specifications and Standards for Food Additives" mainly used as bitter substances and anti-oxidants, and also seven essential oils are registered in "The Japanese Pharmacopoeia Sixteenth Edition". In this study for development of a new method for the quality evaluation of essential oils, we investigated the profile analysis of 16 kinds of essential oils by a taste-sensing system. As the results, 16 kinds of essential oils were classified mainly into 5 types by the taste distributions. Furthermore, we purchased commercial clove and thyme oils, both of which showed high taste intensities in "anionic bitterness" and investigated the relationship between their anionic bitterness intensity and the amounts of the main constituents, namely eugenol and thymol for clove and thyme oils, respectively. In consequence, as clove oils, the "anionic bitterness" intensities of eight samples were approximately the same as those of the corresponding standard samples of eugenol. As for the remaining three samples, more than 70% of the "anionic bitterness" intensity was attributed to eugenol content. These data strongly suggest that the "anionic bitterness" taste of clove oil is mostly derived from eugenol. Meanwhile, as thyme oils, no correlation was observed between the "anionic bitterness" intensity and thymol content. This finding suggests that constituents other than thmol may have a larger effect on the anionic bitterness intensity of thyme oil.

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A specific and reliable method was developed for determining the presence of linamarin, a cyanogenic glucoside in cassava flour and cassava starch, using liquid chromatography-electrospray ionization tandem mass spectrometry. Linamarin was extracted with acetonitrile and then purified by solid-phase clean-up using an NH₂ cartridge column. Isocratic HPLC was used to introduce samples for electrospray negative ionization tandem mass spectrometry. The multiple reaction monitoring (MRM) was performed using a characteristic fragmentation (m/z 246.1→ m/z 161.0) for linamarin. Calibration with a standard solution was linear over a working range of 0.001-0.1 ppm (r²=0.995-0.999), which is equivalent to 0.18-18 μg/g in food samples. The mean recovery of linamarin from cassava flour was approximately 92-100%. The detection limits of the proposed method of linamarin in cassava flour and tapioca samples were 0.75 μg/g and 0.84 μg/g, respectively.

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As the food related issues receive nationwide attention, acquiring knowledge of food safety is critical for customers to carry healthy dietary life. However, it is not necessarily clear what area of the dietary knowledge needed for customers. This paper was made to examine the expert points of view in Food Safety Commission (FSC), an independent public organization which undertakes risk assessment in Japan, with regard to a scope of dietary knowledge which consumers should know. We asked thirty FSC experts to participate in this examination. Twenty-eight of them agreed and ranked food safety topics in order of importance for customers. We analyzed by three-round Delphi technique, a qualitative approach for experts to revise their earlier answers in light of the replies of other members. The response rates at each round were 89.2%, 82.1%, 67.8% in order. After three rounds, 34 topics had been identified. Topics related to 'a way of risk thinking' was ranked the first, and the fourth and tenth are also pertinent topics for risk assessment concerned. FSC members are highly interested in promoting consumers' understanding for food safety risk assessment. As other "Pesticides", "Genetically modified food", "Food additives", "Natural toxins" and "Health food" are ranked in top 10, and by analyzing experts' response, we found that FSC experts required customers to acquire extensive knowledge about these topics. As other studied for dietitians and food sanitation inspectors by three- round Delphi technique, we compared the differences of experts' viewpoints. As a result, we found that each expert had different aspects in terms of consumer food-safety knowledge, and these differences of the aspect derived mainly from that of their expertness and type of the job.

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The water level of PET bottle mineral waters sold on hot summer days seem to vary. This led us to simulate the high temperature condition (37℃) and examine the change in the quantity and quality of natural mineral water in unopened PET bottles. The results showed that approximately 1 g of water was lost per week when the bottle was kept unopened at 37℃. There was also a change in quality, due to precipitation of calcium carbonate, decline of hardness, and decrease of pH.

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A rapid and sensitive method has been developed for determining of sucralose in various foods by high performance liquid chromatography (HPLC) using derivatization. Sucralose in foods were extracted with water in ultrasonic bath, and the extract was loaded onto a strata-X-C, reverse-phase and cation-exchange cartridge. The HPLC separation was performed on a InertSustain C18 column (5 μm, 4.6 mm i.d. x 150 mm) using acetonitrile-H₂O (4:1) as a mobile phase. The injection volume, flow rate and column temperature were 20 μL, 1.0 mL/min and 40℃, respectively. A UV absorbance detector was set to 230 nm. The recoveries of sucralose from foods added at the level 0.2 g/kg and 0.05 g/kg were 75.2-95.6% and 71.6-92.9%, respectively. The recoveries from foods except chewing gum added at the level 0.008 g/kg were 89.0-98.0% and 19.2% in chewing gum. The determination limit was 0.004 g/kg in foods except chewing gum and 0.025 g/kg in chewing gum. Nine commercial foods indicated the using of sucralose were determined by the proposed method. Sucralose was detected in all foods in the range of 0.01-1.26 g/kg. The correlation between the proposed method and the dialysis method was high (correlation coefficient 0.999).

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This is the first report on analyses of characteristic anthocyanins contained in roots of a newly bred sweetpotato, Ipomoea batatas cv. okiyumemurasaki. Cyanidin 3-sophoroside-5-glucoside and peonidin 3-(6-caffeoyl-sophoroside)-5-glucoside were isolated and identified by LCMS and ¹H- and ¹³C-NMR spectral data. It is of interest that these anthocyanins are isolated from this cultivar at a viewpoint of physiologically activity because such non- and mono acylated anthocyanins are absorbed directly in a small intestine after administration of colored sweetpotato.

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