Culture collections (CCs) are organizations that mainly collect strains of microorganisms to stably preserve or maintain them and distribute them to users. There are 23 CCs in Japan ; these are mainly established in universities and national institutes, and contain a total of 411 183 strains of preserved microorganisms (191 692 bacteria, 50 799 yeasts, 49 380 fungi and others), accounting for 20 % of strains preserved in CCs around the world. CCs also store information on their microorganism collections (species, location and origin of isolation, and growth conditions) in databases. These primary data for the identification of strains are open to the public via the Internet, and users can retrieve the data using searching systems offered by the CCs instead of using paper-based catalogs. In CCs, deposited microorganisms are cultured and, depending on the microbial group, freeze-drying or other freezing methods are used to prepare the microorganisms for distribution. At regular intervals, survival tests are carried out to check the quality of the preparations. In addition, CCs offer services other than distribution of their collections, such as e-mail newsletters, workshops on the handling of microorganisms, booklets on the microorganisms, and safety-deposit services for users’ collections.

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Whole wheat flour is rich in dietary fiber, vitamins and minerals when compared with commercial flour lacking bran and germ. However, whole wheat flour prepared by conventional milling contains roughly ground bran and causes elastic deformation of the gluten membrane and degradation of bread quality. Cleaning of the wheat seed coat is an important step in the process of preparing hygienic whole wheat flour. It is also important to prepare fine scratches on the seed coat in order to finely pulverize the bran. Milling of wheat grain was carried out using a stainless steel mortar developed by NFRI, and this enabled the preparation of whole wheat flour with finely pulverized wheat bran. Bread products made from fresh ground whole wheat flour showed high quality with superior flavor. In this study, we outline the novel surface treatment technology used to prepare hygienic whole wheat flour with finely pulverized wheat bran, and the techniques for producing high-quality whole wheat bread from the noodle wheat “Kitahonami”.

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Increases in nitrite ions in tarako, ikura and sujiko during manufacture or cold storage have been observed. We isolated 30 bacterial strains from tarako and examined their nitrite-producing abilities. Eleven strains among the isolates reduced nitrate to nitrite at 0-5 % NaCl and 5-30°C in a succinate-nitrate liquid medium. 16S rRNA gene sequence analysis indicated that these nitrate-reducing bacteria belonged to Vibrio, Halomonas or Cobetia. Two strains (strains No. 6 and No. 19) that showed the highest nitrite production among the isolates, and one strain (strain No. 17) that showed the lowest nitrite production, were inoculated in tarako and mentaiko. Then, they were tested for nitrite production after storage at 5, 10 and 20°C. Results showed that strain No. 19 produced nitrite ions at every tested temperature. We also found that frozen Alaska pollack roe imported from the USA and Russia were contaminated with nitrite-producing bacteria from 8 to 340 CFU/g. These results suggest that the increase in nitrite ions in tarako and mentaiko is due to the reduction of ingredient-derived nitrate to nitrite by nitrate-reducing bacteria that contaminate Alaska pollack roe.

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Collagen synthesis declines with aging. Low protein diet fed rats can be used as a model for aged rats. In the present experiments, we evaluated the collagen content of granulation tissue after oral administration of collagen peptide in aged rats. After administration of 0.2, 1.0 or 5.0 g × kg^-1 body weight collagen peptide for 1 week, weight and hydroxyproline (HYP) content of the granulation tissue were increased in a dose-dependent manner. To directly investigate the collagen content of granulation tissue, collagen was stained with Sirius red/Fast green. Histological analysis clarified that 1.0 g × kg^-1 body weight of collagen peptide increased collagen fiber content in the granulation tissue. Furthermore, we compared the effects of several food-derived peptides or protein on collagen content. All peptides and protein (1.0 g × kg^-1 body weight) increased weight and HYP content of granulation tissue in aged rats. Interestingly, orally administrated collagen peptide was the most effective in increasing weight and HYP content of granulation tissue. These results indicated that oral administration of collagen peptide is effective for increasing collagen content in an aged rat model.

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Commercial roasted coffee beans are commonly degassed. However, we found that a large number of volatile compounds were lost from coffee extracts through this process. Extracts of non-degassed roasted coffee beans strongly enhanced intestinal IgA production in mice. Moreover, we found that 2-methylpyrazine, 2,5-dimethylpyrazine and 2,6-dimethylpyrazine, which were lost by degassing, enhanced intestinal IgA production in mice. These results indicate that if degassing is not carried out, or if degassing time is reduced, roasted coffee beans include sufficient volatile compounds to enhance intestinal IgA production in mice.

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We investigated five commercial types of packaging for green soybeans. The packages consisted of micro-perforated, perforated or non-perforated oriented polypropylene. In-package oxygen concentrations were 9.3 % to 19.7 %. Micro-perforated packages maintained especially high oxygen concentrations, so these were considered unsuitable for modified atmosphere packaging (MAP). Two hundred-gram amounts of green soybeans were packaged in polypropylene (17.3 cm × 18.3 cm ; thickness : 41 μm) with 0, 1, 2, 3 or 4 micro-perforations 209 μm in diameter. The packaged green soybeans were stored at 5°C and their quality was investigated at 1-week intervals for 3 weeks. The flavor of green soybeans packaged in the non-perforated bag was judged to be off after 1 week ; this was attributed to the excessively low oxygen concentration. Bags with 1 or 2 micro-perforations allowed for sufficient oxygen concentrations and maintained high carbon dioxide conditions, so their flavor was judged to be good even after 3 weeks. The green color of the raw beans was maintained in the samples in bags with fewer micro-perforations. However, when the beans were boiled, the green color of all samples became more vivid regardless of the number of micro-perforations in the packaging. The packaged beans hardened over time, whether tested raw or boiled, and the number of micro-perforations in the packaging did not affect this hardening.

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A method based on the 4-dimethylaminocinnamaldehyde (DMAC) method was optimized for determination of total proanthocyanidin content in grain legumes using 96-well microplates. The recovery determined for a milled soybean material spiked with black soybean seed coat extract equivalent to 1.0, 2.0 and 4.2 mg/g of proanthocyanidin ranged from 96.1 to 97.9 %. Duplicate determinations of total proanthocyanidin content in eight different grain legumes were performed on three different days. Statistical treatment revealed that the relative standard deviation of the repeatability (RSD_r) and the relative standard deviation of the intermediate reproducibility (RSD_int) for determination of total proanthocyanidin content was 0.5 to 4.1 % and 0.9 to 4.7 %, respectively. The HorRat values (RSD_int/predicted RSD_R) ranged from 0.17 to 0.87. This demonstrates that the proposed method for determining total proanthocyanidin content in grain legumes had good intralaboratory reproducibility. The contents of proanthocyanidin, ranging from 0.33 to 2.97 mg/g, in 59 samples of black soybean determined by the DMAC method were strongly correlated to those determined by the vanillin-sulfuric acid method (r=0.980). However, the contents in black soybeans determined by the vanillin-sulfuric acid method were higher when compared with the DMAC method in almost all samples, when the content obtained by the DMAC method was directly compared to that obtained by the vanillin-sulfuric acid method.

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