A coliform flora analysis method using real-time polymerase chain reaction (PCR) was developed. The amplified region targeted was lacZ, encoding β-galactosidase. Forty-two species belonging to 16 genera of coliform bacteria were successfully detected. Specific primers were designed to detect the genus Klebsiella/Enterobacter and the genus Citrobacter, allowing for the discrimination of coliform bacteria into 3 groups. Quantification of bacterial numbers ranged from 10³ to 10⁶ cfu per PCR reaction vessel. Differences in flora between vegetables and meat, and among various factory locations, were able to be detected. Finally, sources of contamination were investigated in a real food factory. Coliform bacteria were detected in 23 out of a total of 32 samples. As a result of cluster analysis, 4 potential sources of contamination during the manufacturing process were proposed for the 2 products. Analysis of the flora was completed in approximately 5 hours; thus, a rapid contamination source search system has been developed.

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While okara contains various functional components such as isoflavones, it is typically discarded as industrial waste due to its rapid deterioration. In this study, we prepared beni koji by the fermentation of okara using Monascus anka AOK 2026, followed by examination of changes in antioxidant activities and major components during koji fermentation, as well as evaluation of its utility as a food material. Both antioxidant activities and total polyphenol contents were similarly increased during koji fermentation, and a particularly remarkable increase was recognized at 4-days fermentation; a strong positive correlation was evident between them (r=0.99). Tocopherols content did not change appreciably during koji fermentation; however, isoflavone glucosides were converted to their aglycone form, which can be efficiently absorbed into the human body, by beta-glucosidase produced during M. anka fermentation. As an example of the effective utilization of okara beni koji, cookies containing koji from 0 % to 10 % and 20 % were prepared. The cookie with 10 % koji was evaluated as highly palatable by a sensory test. In addition, the added koji was effective in preventing lipid autoxidation. These results suggest that okara beni koji has the potential to be a new, usable, high value-added functional food material.

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The purpose of this paper was to use metabolomics to investigate the chemical changes occurring in a green tea beverage packaged in polyethylene terephthalate (PET) bottles. The analysis methodology uses trimethylsilyl derivatization followed by gas chromatography-mass spectrometry (GC/MS) and multivariate analysis of principal component analysis (PCA). Bottled tea samples were stored at 4°C (control) or 55°C for 2 and 4 weeks. The samples were pretreated and then derivatized. The data set was analyzed using PCA. Two-dimensional PCA plots were constructed, then the stored tea samples were divided into three groups according to their storage temperature and duration. PCA showed a clear classification reflecting the deterioration of each tea sample and revealed two indicator compounds, identified by GC/MS and LC/MS analysis as xylonic acid and lyxonic acid (belonging to the aldonic acid family). These compounds, generated from ascorbic acid present in the green tea infusion, increased in concentration during storage at 55°C. Thus, the results indicated the presence of a degradation pathway involving ascorbic acid in green tea products.

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We measured the concentrations of 7 minerals in 8 cultivars of pigmented brown rice grown between 2002-2005, then compared these concentrations with those in Koshihikari rice cultivated in the same field. The results showed that the calcium content of pigmented brown rice was higher than that of the Koshihikari cultivar. These results raise the possibility that the potassium, magnesium and phosphorus content of the pigmented rice may be higher than in the Koshihikari cultivar, whereas its zinc concentration might be lower than in the Koshihikari cultivar.

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We found that many volatile compounds were decreased from coffee extracts through a degassing process performed in commercial roasted coffee beans. Extracts of non-degassed roasted coffee beans enhanced serum IgG and IgA production in mice. Moreover, we found that 2,5-dimethylpyrazine and 2,6-dimethylpyrazine, which were decreased by degassing, were mainly involved in the effect. In addition, 2-methylpyrazine enhanced serum IgG production. These results indicate that non-degassed roasted coffee bean extract include sufficient volatile compounds to enhance serum IgG and IgA production in mice.

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Various mushrooms were screened for use in the production of miso from quinoa (Chenopodium quinoa) seeds. Forty mushrooms were cultured in the preparation of quinoa koji on the solid-state medium composed by quinoa and water. The protease activities of the quinoa kojis were assayed, and 14 mushrooms were shown to exhibit high protease activity. Among the 14 strains, 5 edible mushrooms showed salt-tolerance in the presence of 10 % NaCl, and these were used to produce miso from quinoa. The free amino acids content and antioxidant activity of the quinoa miso with mushroom fermentation were higher than that of the quinoa miso without mushroom fermentation and were similar to commercially produced miso.

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Twelve strains of edible mushrooms were cultivated on solid-state medium with wheat bran. Only strain Hericium erinaceum NBRC 100328 showed high milk-clotting enzyme activity. Furthermore, milk-clotting activity was assayed in 7 strains of H. erinaceum obtained from the MAFF culture collection. Among the strains tested, 4 strains showed the activity. Four MAFF and one NBRC strains of H. erinaceum were applied to the preparation of milk curd. All 5 strains were capable of curd production. Of the 5 strains, H. erinaceum MAFF 435060, MAFF 430234 and NBRC 100328 were selected as suitable strains for cheese making.

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Recently, the focus of allergy treatment has changed from prevention to tolerance induction, and hyposensitization using Specific Oral Tolerance Induction (SOTI) for food allergy and SubLingual ImmunoTherapy (SLIT) for hay fever have been attracting attention. We found that food proteins ingested maternally exist as IgA immune complexes in breast milk, thereby inducing oral tolerance in the offspring. Breast milk is typically the first meal for humans, and may thus represent the first natural drinkable vaccination against food allergens for babies. In this report, evidence supporting this hypothesis and recent knowledge regarding its application are reviewed. We hope that this report will stimulate the re-evaluation of breast-feeding based on the mammalian origin.

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