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The effects of fermentation temperature(0∼15℃) and salt concentration(1.5∼4.0%) on the fermentation property of Chinese cabbage Kimchi were analyzed by response surface methodology. The pH decreased and acidity increased with increasing fermentation time. The reduction and increment velocities of pH and acidity were increased by increasing fermentation temperature and decreasing salt concentration. The optimum pH 4.2 was reached within 14∼24 days at 5∼15℃, while pHs of 24 days at 0∼5℃ were still lower value than 4.2. The effect of salt concentration more affected terminal fermentation period than initial fermentation period. The maximum edible acidity, 0.75%, was reached within 8 days at 15℃, while acidifies of 24 days at 0℃ were 0.35∼0.43%. The effects of salt concentration at 0℃ was higher than those at 15℃. The fermentation time, fermentation temperature and salt concentration were the first, second and third affecting factors on the pH and acidity of Kimchi. Based on the coefficients of determination, pH and acidity were highly fitted to the experimental data(r²$gt;0.9276). For the suitable acidity range, 0.40∼0.75%, the edible period of Kimchi at 15℃, 10℃ and 5℃ were 4 days, 10 days and 18 days at the 2.75% of salt concentration, respectively. The edible period increased from 14 days to 19 days with increased salt concentration from 1.50% to 4.00% at 5℃ of fermentation temperature.
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