We investigated the effect of continuous supplementation of drinking water with silicate for 7 weeks to broilers on the level of functional ingredients and taste in chickens. The functional ingredients and taste components were measured using HPLC, and the taste was evaluated by sensory evaluation of the breast, thigh, and tenderloin, respectively. Analysis of functional ingredients revealed that the level of anserine in the breast and tenderloin as well as the level of carnosine in the tenderloin in the high-dose silicate solution-supplemented group were higher than those of the control group. Analysis of ATP-related compounds revealed that the inosinic acid level decreased in the breast and thigh but did not decrease in the tenderloin. In addition, analysis of free amino acids indicated that the level of glutamic acid exhibiting umami taste increased in the tenderloin. Furthermore, sensory evaluation revealed that the umami taste of tenderloin in the high-dose silicate solution-supplemented group was significantly higher than that of the control group. In conclusion, our findings suggested that the supply of drinking water containing silicate increased the level of functional ingredients in the breast and tenderloin in broilers and improved the umami taste of chicken tenderloin. Therefore, supplementation with silicate may be beneficial as a feed additive for better rearing of broilers.

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Free amino acids, catechin content, and inhibitory effects against carbohydrate absorption in rats were assessed for “matcha” of different qualities. Among the tested matcha from three different companies, low-quality matcha was found to have more powerful inhibitory action on carbohydrate absorption than high-quality matcha. With regard to the structural components of matcha, free amino acids were more abundant in high-quality matcha, and were less abundant in low-quality matcha. On the other hand, catechin content was lower in high-quality matcha, but was higher in low-quality matcha. These results indicate that low-quality matcha, which has a higher catechin content, has greater functionality than high-quality matcha. It may therefore be possible to increase the utility of low-quality matcha by using it as an ingredient in functional foods.

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Lately, new plant biotechnologies, termed New Breeding Techniques (NBT), have appeared and are attracting attention worldwide. Their development is proceeding rapidly as the next-generation gene technology following the present genetically modified (GM) technology. A psychological experiment was conducted to show the effect of material for explaining NBT on consumers’ attitude with 100 housewives having children in Tokyo, Japan. The results showed that giving information about NBT crops through PowerPoint slides decreased risk perception and increased acceptance of NBT crops among the participants. We also found that this effect persisted for more than three months at least. In contrast, the effect of giving information about risk literacy was not verified.

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The concentration of phenolics (feruloylglucoside and flavonoid) in Allium macrostemon Bunge (103 plants in November 2016 and 98 plants in April 2017), which have been collected in various area of Japan and cultivated at Saga University, was determined by HPLC analysis. Although some plants showed high concentration of feruloylglucosides including allimacronoid A and flavonoids (glycosides of kaempferol and quercetin), the definite relationship between the phenolics concentration and the harvest points of the plants was not observed. The most plants, collected in the northern Japan and the areas along the Sea of Japan, showed relatively high concentration of the flavonoid such as kaempferol 3-O-sophoroside-7-O-glucuronide.

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In this study, an analytical method for determining cyclopiazonic acid (CPA) in cheese using solid-phase dispersive extraction (SPDE) followed by 1iquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed, and the method was applied to the analysis of commercial cheese samples. The cheese sample was homogenized with 80% (v/v) ethanol, and CPA was extracted using ethyl acetate; then, SPDE using Oasis^® MCX was performed. Thereafter, the sample was subjected to LC-MS/MS analysis. Using the proposed method, the limit of detection (LOD) was 0.2 ng/g for cheese samples. The method achieved sufficient sensitivity to determine CPA in cheese samples. CPA-spiked cheese samples were prepared (a low concentration of 10 ng/g and a high concentration of 50 ng/g) for validation study. The recoveries of the low- and high-concentration samples were 70.4% and 81.2%, respectively. The relative standard deviation (RSD) of repeatability and intermediate precision were 10.1% and 10.1% for the low-concentration sample and 8.3% and 15.0% for the high-concentration sample, respectively. The proposed method was applied to commercially available cheese samples, 8.9 ng/g of CPA was detected in one imported camembert cheese sample. These results indicated that the proposed method is useful for determining CPA in cheese samples.

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In April 2015, “Foods with Functional Claims (FFCs)” was established as a new category of labeling in health food products sold in Japan, and we have already found some FFCs with poor-quality for functional component level. To ensure the efficacy and safety of the FFCs, effective quality control on the validity of the original plants, the consistency of components, and manufacturing process is important for the herbal ingredients with specific health-related functions in FFCs. In this study, we evaluated the amount of isoflavones in 8 FFCs of which functional components are Puerariae thomsonii flower-derived isoflavones (as tectorigenin derivatives). These FFCs contained 39.9 ~ 49.0 mg/day of tectorigenin derivatives (sum of tectorigenin 7-O-(6-O-xylosylglucoside), tectoridin, and tectorigenin), corresponding to 106 ~ 117% of the labeled values within a small margin of error. This result indicated that the tested FFCs have as high quality as herbal medicinal products for the chemical component level. Additionally, the aglycone content (tectorigenin equivalents) in 8 FFCs ranged from 25 to 31 mg/day. Since tectorigenin derivatives is thought to have strong estrogenic effects even though their binding affinities for estrogen receptors are weak, further investigation and discussion would be needed for ensuring the efficacy and safety of FFCs containing Puerariae thomsonii flowerderived isoflavones.

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The aim of this study is to elucidate and reconstruct paleo diets using the carbon and nitrogen isotope ratios (δ¹³C and δ¹⁵N) of charred residue on earthenware pots. It is necessary to consider whether there are any significant differences in the δ¹³C and δ¹⁵N values of modern foods between before and after cooking. In this study, we investigated the changes occurring during the boiling of foods (sea bream, coho salmon, hard-shell clam, wakame, rice, and millet) in the earthenware pot. In addition, we examined the fluctuations in δ¹³C and δ¹⁵N values in the charred residue. We defined the cases where δ¹³C and δ¹⁵N values varied by more than 1.0 ‰ and 3.0 ‰, respectively, as “varied”. The δ¹³C “variation” was small within 1.0 ‰ except sea bream which indicated decreases of 1.4-1.8 ‰. The change in δ¹⁵N values was less than 3.0 ‰ in all charred residue samples. The δ¹³C and δ¹⁵N values were likely to be almost maintained during boiling. This result suggested that δ¹³C and δ¹⁵N values of charred residue depended on the food group, such as fish, shellfish, seaweed, and C₃ and C₄ plants. Thus, we may discriminate the food groups of charred residues using their δ¹³C and δ¹⁵N values.

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Standard Methods for the Analysis of nitrite can be inaccurate because of the instability of nitrite. Therefore, calibration curves need to be plotted for each new sample, and processing many samples is time consuming. To overcome these issues, we examined the use of additives in extracts to improve the stability of nitrite during extraction and quantification processes. Oxidizing agents (hydrogen peroxide, potassium nitrate, and potassium permanganate), reducing agents (ascorbic acid, glucose, sodium oxalate, and sodium sulfite), chelating agents (cyclohexanediaminetetraacetic acid, and EDTA) that can suppress oxidation by metal ions, and an organic solvent (chloroform) than can suppress oxidation and reduction by microorganisms were selected as additives. For each additive, a series of ten-fold dilutions from a 1 M stock solution were used to prepare a range of solutions with concentrations between 0.01 M and 10⁻⁷ M, except for chloroform, which was used at a volume fraction of ≥ 1%. First, we investigated if these additives inhibited color development in the Griess reaction. Next, we evaluated if the additives suppressed decomposition of nitrite in standard solutions stored for 1 week. Finally, we investigated suppression of nitrite decomposition in actual food extracts stored for 1 month. Optimum quantitation of nitrite was possible for extracts stored for ≥ 2 weeks when EDTA was added to them at 0.01 M.

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