• Clean Technology
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• v.19 no.2
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• pp.148-155
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• 2013

Volatile fatty acids (VFAs) production from marine brown algae, Saccharina japonica, was investigated in anaerobic dark fermentation. In order to evaluate the VFAs productivity, various experimental parameters (i.e., physicochemical pre-treatment, microorganism inoculation ratio, substrate concentration, and pH) were evaluated. According to the physicochemical pre-treatment methods, the maximum concentrations of VFAs were obtained in the order of sulfuric acid, subcritical water and subcritical water with lipid-extraction. Also, we investigated the operating parameters such as microorganism inoculation ratio (MV/M = 10 to 30), the substrate concentration (18.0 to 72.0 g/L) and pH (6.0 to 7.0) in sulfuric acid pre-treatment method. When the substrate concentrations were 18.0, 36.0, 54.0 and 72.0 g/L at $35^{\circ}C$, microorganism inoculation ratio 15, pH 7.0 for 372 hours, the maximum concentrations of VFAs were respectively 9.8, 13.9, 18.6 and 22.3 g/L. The change in VFAs concentrations was detected that acetic- and propionic acids increased according to increasing pH, while the butyric acid increased with decreasing pH. The VFAs obtained from concentration and separation process may be used as basic chemistry materials and bio-fuel, and they will expect to produce alternative energy of fossil fuel.

• Food Science and Preservation
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• v.13 no.6
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• pp.740-748
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• 2006

The Chunma (Gastrodia elata Blume) requires a simple pre-treatment, due to inconvenience or preservation, toxicities, and pungencies in intact state. Various drying conditions were examined to establish the physicochemical properties of Chunma by the response surface methodology (RSM). Weter activity and total phenolic acid contents of Chunma dried extracts were optimal at $79.56^{\circ}C$ and $79.64^{\circ}C$ for 7.17 hr and 8.74 hr, respectively, for their characteristics. Electron-donating ability and nitrite-scavenging activity were optimal at 79.79 and $7.99^{\circ}C$ for 8.57 and 8.07 hr. We generated a regression equation for each variable and then superimposed the optimal condition in acquiring values for each frying process factor, physicochemical properties, resulting in that the optimal drying condition was at $75{\sim}80^{\circ}C$ for $8{\sim}9 hr$.