Fermentation is a method of food preservation that breaks down carbohydrates to create lactic acid. Kimchi is a traditional Korean dish made of fermented cabbage or cucumbers and other vegetables and flavorings. Salt and liquid are the only elements necessary for fermentation. Fermentation does not require cooking, so the nutrients in the vegetables are preserved, making kimchi a nutritious condiment. The fermentation process begins within a few days, and can preserve food for several weeks.
Prepare the Kimchi
Cut the cabbage into quarters, keeping each quarter intact with leaves attached to the core.
Dissolve 1 cup salt in 1/2 gallon water. Soak the cabbage in the saltwater for 3 to 4 hours.
Pulse garlic, ginger and fish sauce in a food processor until finely minced.
Combine mustard greens, radish, green onions, garlic mixture, chili powder, 1 tbsp. salt and sugar (optional) in a large bowl. Toss gently until thoroughly mixed.
Drain cabbage and rinse thoroughly. Squeeze out as much water as possible.
Stuff mustard green and radish mixture between the leaves. Start from the outside with the largest leaf and work your way in. Do not overstuff. Wrap one large leaf tightly around each stuffed cabbage quarter.
The Fermentation Process
Put the stuffed cabbage into the jar or divide among jars. The salt will draw the water out of the cabbage, so no additional liquid is needed. Press down to release any air bubbles. Seal.
Let sit for two to three days in a cool place. Fermentation begins after a few days, and becomes stronger over time.
Taste the kimchi periodically until it is ripe enough for your liking. Fermentation continues over several weeks.
Refrigerate fermented kimchi after opening. Fermented kimchi can be eaten straight from the jar for up to three weeks. After about four weeks it is too fermented to eat alone, but it still good for mixing into recipes like dumplings and fried rice.
Korean chili powder is very spicy. If mixing with your hands, wear gloves to avoid skin burns.