• Korean Journal of Food Science and Technology
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• v.16 no.2
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• pp.133-138
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• 1984

For the purpose of improving the precooked frozen food, the processing conditions of sardine steaks and the effect of soybean protein and corn starch on quality of the products during frozen storage were investigated. Fresh sardines were purchased from Busan Central Whole Sale Market and filleted. And then sardine meats were separated from fillets by fish meat separator. The meats were mixed with 0.5% sodium bicarbonate, 1.5% of table salt and 0.2% of polyphosphate, monosodium glutamate, white pepper, garlic powder and nutmeg, respectively. The mixture was minced with the stone grinder and filled in polyvinylidene chloride film tube and then stored at $-3^{\circ}C$ for 36 hours prior to frozen storage. Sardine steaks containing 3% of soybean protein were superior to those of containing 3% of corn starch or without soybean protein and corn starch on texture and eating quality of them during the period of frozen storage. It is convinced that addition of 3% of soybean protein to the sardine steak was benefically effective for the control of free drip, oxidative rancidity and the improvement of texture. The quality of frozen sardine steaks, by sensory evaluation, were preserved in good eating quality for 90 days during frozen storage.

• Resources Recycling
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• v.27 no.6
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• pp.59-67
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• 2018

Efflorescence is a white deposit of powders in the surface of cement concrete which can also occur in geopolymers. Efflorescence occurs when sodium ions in alkali activator react with atmospheric carbon dioxide to form sodium carbonate components. In this study, we investigated whether the secondary efflorescence can be reduced by controlling the Na/Al mole ratio or by changing the curing temperature and heat curing time in fly ash-based geopolymers. The 28 days compressive strength in geopolymers having Na/Al ratio of 1.0 was higher than geopolymers having Na/Al ratio of 0.8. The strength increased with the increasing curing temperature and longer heat curing time. On the other hand, efflorescence was lower when the curing temperature was high and the heat curing time was longer in the geopolymers having Na/Al ratio of 1.0. The geopolymers having Na/Al ratio of 0.8 showed accelerated efflorescence occurrence than the geopolymers having Na/Al ratio of 1.0. In order to reduce the occurrence of the secondary efflorescence of fly ash-based geopolymers, it will be advantageous to maintain the Na/Al ratio at 1.0, increase the curing temperature, and lengthen the heating curing time.