• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.4
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• pp.413-426
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• 2014

This study was conducted to investigate changes of physicochemical properties and fatty acid compositions of rough rice stored at different storage temperatures and periods. So we analyzed texture, alkali digestion value (ADV), toyo glossiness value, pasting properties, fat acidity and fatty acid compositions of five rice varieties every 4 month on the condition of which rough rice had been stored at different temperatures (ambient and low temperature condition at $15^{\circ}C$) for 2 years. Hardness of cooked rice was increased by storage periods and cohesiveness of cooked rice was not considerably different among varieties according to storage temperatures and periods. ADV was significantly different among varieties and storage periods but not different with storage temperatures. Toyo glossiness value of cooked rice was continuously decreased from 4 months after storage regardless to storage temperature. The pasting properties were considerably affected by storage temperatures and periods of rough rice. Increase in peak viscosity, final viscosity and breakdown was observed but setback was decreased by storage periods. Fat acidity of brown rice was much higher than that of milled rice during storage of rough rice and tend to increase by storage period. Oleic acid among fatty acids of brown rice except Sindongin and Hitomebore tended to be decreased by storage periods and linoleic acid among fatty acids of brown rice of Hopum was decreased by storage periods. The contents of linoleinic acid and stearic acid among fatty acids of milled rice were comparatively decreased from 4 months after storage, whereas the content of palmitic acid tended to be increased by storage periods.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.12
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• pp.1381-1389
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• 2007

Wastewater discharged by industrial activities of metal finishing and electroplating units is often contaminated by a variety of toxic or otherwise harmful substances which have a negative effects on the water environment. The treatment method of heavy metal-cyanide complexes wastewater by alkaline chlorination have already well-known($1^{st}$ Oxidation: pH 10, reaction time 30 min, ORP 350 mV, $2^{nd}$ Oxidation: ORP 650 mV). In this case, the efficiency for the removal of ferro/ferri cyanide by this general alkaline chlorination is very high as 99%. But the permissible limit of Korean waste-water discharge couldn't be satisfied. The initial concentration of cyanide was 374 mg/L(the Korean permissible limit of cyanide is 1.0 mg/L max.). So a particular focus was given to the treatment of heavy metal-cyanide complexes wastewater by $Zn^{+2}/Fe^{+2}$ ion and coprecipitation after alkaline chlorination. And we could meet the Korean permissible limit of cyanide(the final concentration of cyanide: 0.30 mg/L) by $Zn^{+2}/Fe^{+2}$ ion and coprecipitation(reaction time: 30 min, pH: 8.0, rpm: 240). The removal of Chromium ion by reduction(pH: 2.0 max, ORP: 250 mV) and the precipitation of metal hydroxide(pH: 9.5) is treated as 99% of removal efficiency. The removal of Copper and Nickel ion has been treated by $Na_2S$ coagulation-flocculation as 99% min of the efficiency(pH: $9.09\sim10.0$, dosage of $Na_2S:0.5\sim3.0$ mol). It is important to note that the removal of ferro/ferri cyanide of heavy metal-cyanide complexes wastewater should be employed by $Zn^{+2}/Fe^{+2}$ ion and coprecipitation as well as the alkaline chlorination for the Korean permissible limit of waste-water discharge.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.1
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• pp.52-59
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• 1986

As one of trials to process instant sardine foods which can be preserved at room temperature, three kinds of products were prepared as seasoned-dried product (control, C), liquid smoked seasoned-dried product(S) and antioxidant treated seasoned-dried product(E), and their processing conditions and quality stability during storage were examined. Raw sardines were dressed, steamed and then filleted. The sardine fillets were seasoned with the mixed seasoning solution containing $28.0\%$ of sorbitol, $14.0%$ of sugar, $5.6\%$ of table salt, $1.8\%$ of monosodium glutamate, $0.6\%$ of garlic powder and $50.0\%$ of water at $5^{\circ}C$ for 15 hours, and dipped for 45 seconds in $10\%$ Smoke-EZ solution. After liquid smoking, the seasoned and liquid smoked sardine fillets were dried at $45^{\circ}C$ for 4 hours, vacuum packed in laminated plastic film bag(polyester/casted polypropylene= $12{\mu}m/70{\mu}m,\;15{\times}16cm$), and finally pasteurized in water at $95^{\circ}C$ for 30 minutes. The results obtained from chemical and microbial experiments during storage are as follows : the moisture contents, water activity and pH of the products showed little change, and VBN of them slightly increased during storage. The TBA value and POV of the products (E, S) were lower than those of control product(C) considerably. In color values, L value (linghtness) decreased while a and b value (red and yellow) revealed a tendency to increase during storage. The fatty acid composition of the products were similar to those of raw sardine, the predominant fatty acids were 16:0, 20:5, 18:1 and 22:6. The products (E, S) have a good preservative effect on highly unsturated fatty acids during storage. Viable cell counts of those products were negative and histamine contents were less than 2.0 mg/100 g. Among the texture profiles, hardness, elasticity and cohesiveness of the products slightly decreased during storage. Judging from the sensory evaluations, liquid smoked seasoned-dried product(S) was the most desirable, and the products could be preserved in good condition for 40 days at $25{\pm}3^{\circ}C$.