Delipidated and dehydrated starfish, Asteropecten scoparius, Asterias amurensis Asterina pectinifera and Distolasterias nippon were calcined and powered to test their bactericidal effects for foodborne disease causing bacteria. The powders calcined at 55°C showed merely inhibition for the growth of Escherichia coli 0-157 : H7, Staphylococcus aureus and Salmonella enteritidis. However, the powders calcined at 700°C completely inhibited the bacterial growth at over 0.4% (minimal concentration tested). CaCO₃, a major chemical constituent of the starfish, changed to CaO by calcination at 700°C or higher. The Asterias amurensis and Distolasterias nippon powders calcined at 900°C for 10 hrs consisted of Ca, Mg, Na and Cl, of 72-77, 11-15, 5.4-6.4 6.4 and 2.9-4. 3%, respectively, as the major minerals. Even in 0.02% aqueous solution of the powders procured by calcination at 800°C, the pH values indicated were around 11.5, and 0.2% solution had about 12.5 of high alkalinities. From the results, it seems that the bactericidal effect of calcined powder of starfish could be attributed to the multiple effects of high alkalinity and other trace elements.

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The nineteen isothiocyanate compounds with five kinds of functional groups, alkyl, ω-alkenyl, aryl, -methylthioalkyl, and ω-methylsulfinylalkyl, were tested for minimum inhibitory concentration against growth of four species of bacteria and two species of fungi. In general, the isothiocyanate (ITC) analogues showed antimicrobial activities according to the following order : aryl ITC > ω-methylthioalkyl ITC> ω-alkenyl ITC> ω-methylsulfinylalkyl ITC > alkyl ITC. They also had different antimicrobial spectra. The aryl and ω-mithylthioalkyl ITCs indicated higher antimicrobial activity against gram-positive becteria and fungi than gram-negative bacteria, whereas ω-alkenyl ITCs were more effective against gram-negative bacteria and fungi than gram-positive bacteria. Gram-positive bacteria and A. niger were more sensitive to the ω-methylsulfinylalkyl ITCs than gram-negative bacteria and C. albicans. The antimicrobial activity was increased by a combination of ITCs having different antimicrobial spectra. The ITCs other than alkyl ITC inhibited the growth of methicillin resistant Staphylococcus aureus and methicillin sensitive S. aureus at the same concentration. The antimicrobial activity of ITC analogues other than alkyl ITC is about 5 to 10 times those of preservatives generally used in foods.

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Effect of vibration by simulated truck transportation on respiration rate and quality of strawberry fruits was investigated. Vibration data were actually recorded by truck transportation, and a vibration experiment using the data was carried out with a trans-simulation vibrator in the laboratory. 1) Before the vibration, the respiration rate (carbon dioxide production) of strawberry fruits was approximately 30 mg/kg/hr during storage at 5 °C and 70 mg/kg/hr at 15°C, respectively. During the vibration, the respiration rate increased rapidly to 50 mg/kg/hr at 5°C and 84 mg/kg/hr at 15°C, respectively. The level of respiration rate during the vibration was kept higher than that before the vibration. After the vibration, the respiration rate decreased gradully to the initial level within 1 hr. 2) The vibration damaged the quality of appearance is strawberry fruits, and the quality was lower than that of fruits of non-vibration. Further more, storage temperatures also affected strawberry fruits, and the quality of fruits at 5°C was maintained higher than that of fruits stored at 15°C. 3) The decrease of flesh firmness was observed by the vibration. Flesh of fruits stored at St was maintained firmer than that at 1St. 4) No effect of the vibration was found with respect to solible solid, acidity and vitamin C content of strawberry fruits.

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Squid livers prepared by 10% salt as the whole were matured during preservation for 10 days at 20°C in the dark. The changes in the water activity, contents of moisture and total lipids of the sample were measured each day during preservation. The water activity was maintained at 0.73 throughout the period, and the moisture and the total lipid contents after storage were approx. 33% and 43%, respectively. Free fatty acid fractions increased gradually accompanied by changes in the ratios of poly unsaturated fatty acids during preservation. The amount of hydroperoxide increased as well as changes in free fatty acid fractions within a week, but the extent of lipid peroxidation was slight after storage. The stability of the lipid peroxidation in squid liver was maintained during preservation even at a relatively low level of salting.

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