Nasunin is a major pigment in the skin of eggplant cultivar 'Mizunasu' fruit. The surface color is an important factor of eggplant's quality. Therefore, the visible-near-infrared reflectance spectroscopy (Vis-NIRS) was used to estimate nasunin content nondestructively and rapidly. Actual nasunin contents were extracted with 5% formic acid and analyzed absorbance at 525nm by spectrophotometry. The absorbance on the surface of 'Mizunasu' fruits by Vis-NIBS was generally high value except nearby edges in the range of visible wavelength. Forty-four samples of calibration set were used to select the strongest correlating wavelength of the Vis-NIRS spectra with the nasunin contents. The best wavelength was 710nm. From this relationship, a calibration equation as a nondestructive method, Y=1.1975X-0.0594 (Y: predicted nasunin content, X: absorbance at 710nm) was obtained. The correlation coefficient was 0.93. Other 36 samples of prediction set were used to evaluate the equation. The correlation coefficient and standard error of prediction were 0.92 and 0.034, respectively. There was a peak at 555nm in the extract with 0.2 M-phosphate buffer, pH 7.0. The multiple correlation coefficient and standard error of prediction were 0.94 and 0.030, respectively. These relationships allow us to use one or two wavelengths for the calibration equation for nasunin content in the skin of eggplant 'Mizunasu' fruit in situ.

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The properties of ostrich egg were examined by measuring proportional parts, shape index, yolk index, percentage of thick albumen, pH of albumen and yolk, chemical compositions, color, rheological properties of albumen, compared with those of white leghorn hen egg. The shell of ostrich egg was extremely thick, the ratio of shell weight to egg weight was 20.0% (12.4%: hen egg), and yolk index was 0.17 (0.39: hen egg). Chemical properties of ostrich egg were similar to those of hen egg. The adhesion in physical properties of ostrich egg albumen was higher than that of hen egg. SDS-PAGE patterns of albumen and yolk were different between ostrich egg and hen egg. As the weight of ostrich egg is about 20 times as much as that of hen egg, ostrich egg is expected as an useful food resource.

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Staphylococcus xylosus 41 was selected from bacteria isolated from cured meat for use in an experiment to improve the sensory properties of cooked cured pork loin. The selection was based on its growth temperature, salt-tolerance, nitrite tolerance, aerobic and anaerobic growth, and proteolytic activity. A fermented pork extract, which is the supernatant of pork suspension solution fermented for 5 days at 25°C after inoculation of S. xylosus 41, had a slightly strong characteristic flavor. Cooked cured pork loin produced by using this fermented pork extract was evaluated to have better flavor and significantly (p<0.05) better taste than those of cooked cured pork loin containing a nonfermented pork extract. The amounts of protein and total amino acids in the fermented extract were less than those in the nonfermented extract, presumably due to decomposition of the protein in the pork suspension solution and absorption of the decomposed amino acids by S. xylosus 41. Acetic acid was produced in the fermented extract, and it was thought to contribute to the improvement in taste of the cooked cured pork loin. Only three kinds of amino acid, glutamic acid, leucine and proline, remained in the fermented extract, and it was thought that they also contributed to the improvement in taste of the cooked cured pork loin. Peptides with higher and lower molecular weights were produced in the fermented extract than those in the nonfermented extract, suggesting that decomposition of proteins to peptides and amino acids proceeded rapidly. From these results, it was concluded that the sensory properties of cooked cured pork loin can be improved by injecting the pork extract that has been fermented by S. xylosus isolated from cured pork loin.

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The volatile component in commercial itohiki-natto was extracted with divinylbenzene/carboxen/polydimethylsiloxane solid-phase microextraction fiber at 50°C for 60min, and injected by gas chromatograph (GC) or gas chromatograph mass spectrometer (column: DB-WAX (0.25mm ID, 30m long, 0.25μm film thickness)). Each peak was identified by comparing the mass spectrum and the retention indices with the mass spectrum data bases and the retention indices of authentic compounds, respectively. Twelve alcohols, 20 ketones, 12 fatty acids, 12 nitrogen compounds, 10 hydrocarbons, 8 esters, 3 phenols, 2 frans, 1 aldehyde, 1 pyrane, 1 oxazole, and ammonia, and total 83 compounds were identified. The quantitative comparison was carried out by addition of an internal standard of 2-heptanol (100ppm aq, 10.0μl) into the vial, and it was done by the gas chromatograph equipped with FID. By comparing the peak area between major odor compounds and internal standard, the concentration was obtained. The abundance of the volatile components is greatly different between each product. Especially, in the product using Natto-bacteria mutant which does not produce the low molecular branched fatty acid, there were small content of isobutyric acid, 2-methylbutyric acid and isovaleric acid. These measurement result agreed with the odor difference.

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Royal jelly from the honeybee, Apis mellifera, is traditionally known to have some diverse nutritional and pharmacological functions. In order to clarify the potential physiological function of royal jelly, angiotensin-I converting enzyme (ACE)-inhibitory activities of its several protease digests were investigated. Not intact royal jelly but some protease digests showed ACE-inhibitory activities. The digests produced by Bacillus subtilis protease, protease N, had ACE-inhibitory activities with the 50% inhibition against ACE at 0.25mg/ml, which is the most potent among the various protease digests. The ACE-inhibitory activities of the protease-N digest did not change after further digestion by pepsin, trypsin and chymotrypsin. These results suggest that ACE-inhibitory activities in the protease-N digests were stable without being digested by gastrointestinal enzymes.

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