The first step in fermenting kimchi is salt pickling.
The salt reacts with enzymes in the cabbage to break down proteins and begin fermentation immediately. This process continues even at cold temperatures. Traditionally, kimchi was allowed to ferment slowly during the cold winter weather.
The taste of kimchi also depends on the seasonings used.
Typical seasonings include green onion, garlic, ginger, salted fish, and chili powder. The combination of spices chosen determines the overall taste of the kimchi.
Fermentation Rates for Kimchi
Adding a lot of garlic, seafood, onions, chili powder, cucumber or green onions makes kimchi ferment more quickly. Adding salted oysters, salted shrimp or persimmon sauce really speeds up fermentation. On the other hand, adding leeks, mustard or ginseng slows down fermentation.
Kimchi begins fermenting as soon as it is prepared.
Contact with air will make kimchi sour. If the kimchi is not covered in sauce or has too little salt, a thin skin of yeast will form on its surface.
Keep air away from the vegetables by covering them in sauce or placing the kimchi in a plastic bag or covering it with plastic wrap.
How Temperature Affects Kimchi
Temperature affects the fermentation rate of kimchi. Colder temperatures slow the fermentation rate.
Long-Term Storage of Kimchi
Like cheese, kimchi is a living organism and will change over time. To keep kimchi fresh for long periods, increase the salt content and store at a low temperature, near 32°F (0°C).
Press vegetables down so they are covered with sauce and cover the container with plastic wrap or a layer of cabbage leaves to keep air out and keep kimchi fresh longer.
Choosing the Right Cabbage for Kimchi
There are many different kinds of cabbage available. For kimchi, choose a medium sized cabbage which is rounded rather than long and thin. The inner leaves should be sweet and paler than the outer leaves. Outer leaves should be thin and light green.
Selecting Radishes for Kimchi
There are many types of radish kimchi, and different radishes are used for different types of kimchi.
For radish kimchi, use Korean radishes that have pale green tops and well-spread leaves.
For chonggak (young radish) kimchi, use Seoul radishes that have round, thick bottoms.
For kkakdugi (cubed radish kimchi), try to find radishes with white rather than green tops.
For dongchimi, use radishes with soft leaves and white rather than green tops.