2.5. Fermentation of tofu with kimchi seasoning
Compositions (w/w) of kimchi seasoning were as follows: Ground Chinese cabbage 75%, red pepper powder 8.0%, minced garlic 4.0%, minced ginger 2.5%, white sugar 4.5%, salt 3.0% and fermented anchovy juice 3.0%. Tofu was crushed by hands, mixed with kimchi seasoning at a ratio of 1:0.5 and 1:1 (w/w) and fermented without and with a starter belonging to the Lactobacillus plantarum group for 16 weeks at 20 °C. During fermentation, tofu and kimchi seasoning (TK) samples were taken after 1 week and at 4-weeks intervals. Half of the sample was used for measurement of pH and LAB count, and the other half was freeze-dried (PVTFD20R, Ilshin lab., Suwon, Korea) and stored at −70 °C for subsequent measurement of antioxidant activities and free amino acids.