To improve microbiological quality of Aster scaber during storage and distribution, hurdle technology with the sanitizers and packaging methods was used. After blanching, total aerobic bacteria of Aster scaber treated with 20% ethanol and 10% NaCl were measured at 2 log CFU/g after 6 days. Total aerobic bacteria of blanched Aster scaber at 100℃ were measured at 2 log CFU/g, and the storage at 4℃ effectively inhibited the growth of bacteria. Repeated blanching using water with added NaCl at 80℃ showed similar microbial growth inhibition compared with treatment at 100℃. After vacuum packaging, blanched sample showed 2 log CFU/g of total aerobic bacteria during 10 days (the storage at 4℃). Therefore, repeated blanching using the water with added 10% NaCl improved the microbiological quality of Aster scaber. We also found that repeated blanching after vacuum packaging was an effective way for storage and distribution of Aster scaber. In conclusion, blanching two times in the 10% salt water or in vacuum packaging at 80~100℃ would be helpful to control the microbes during storage and distribution.

In this study, oyster shells were processed and classified into sizes equal to or smaller than the fine aggregate threshold, and their engineering properties and fire-resistant performance were examined. The differences in heating weight loss of oyster shell aggregate (OSAs) with different particle sizes were examined using thermogravimetric analysis (TGA). The TGA results showed indicating that the temperature at which decarboxylation reaction started depended on the OSA particle size. The porosity of mortar specimens was analyzed using mercury intrusion porosimetry (MIP). The porosity area and porosity of the OSA-containing mortar increased with decreasing particle size. Mortar fire-resistant boards with heated for 2 h in accordance with the heating conditions of KS F 2257-1(methods of fire-resistant testing for structural element—general requirements) to measure their back-side temperature. The board made with OSA2.5 exhibited 273.2 °C, which is more than 90 °C higher than the back-side temperature of the board with OSA 0.6Under. Such difference was attributed to the greater heat transfer delay caused by higher porosity, porosity area, and specific surface area in OSAs with small particle sizes. The TGA results combined with the heating test results suggested that CO2 would be generated at different temperatures in boards containing OSAs with different particle sizes because of the differences in the endothermic reaction temperature.