What is Kimchi?

Kimchi is a healthy & delicious traditional Korean staple that accompanies every meal (even non-Korean dishes). It is a naturally fermented pickle made from:

• variety of produce (napa cabbage, radish, mustard greens, beets, etc)

• aromatics (onions, garlic, green onions, ginger)

• salt

• seasoning (red chili pepper flakes, fish sauce, salted shrimps).  

By fermenting kimchi, it creates the effervescent quality that kimchi is well-known for, accompanied by its distinct tangy, sour, spicy and savory flavors.

Koreans, like many other cultures around the globe, used fermentation as a method of preserving food prior to refrigeration, to nourish during periods of lack.  Traditionally in Korea, the community came together after the late harvest to preserve its yield; this collective activity is called kimjang, a time of making and sharing kimchi.  Family members, relatives and neighbors, regardless of age, all contributed to making large volumes of kimchi that would sustain families throughout the harsh winter until the following spring when fresh crops were available again.

The finished kimchi was stored in large earthenware containers (onggi) and buried in the ground, where the temperature-regulated environment protected its contents from freezing.

FERMENTATION

Fermentation is an ancient method, but today, we are seeing its revival. Many look to kimchi for its health benefits, others simply for its flavors. But how kimchi is made, has not changed much.  

Kimchi is a lacto-fermentation. It starts naturally with the raw materials that already contain numerous micro-organisms, and of these micro-organisms, it is the lactic acid bacteria (LAB) that is primarily responsible for the fermentation. LABs convert carbohydrate (sugar, starches) to lactic acid, which is the dominant byproduct, followed by carbon dioxide and organic acids.

To create a supportive environment for LABs to proliferate, we start with a brine. Brining the main vegetable is a crucial step in the initial stage of fermentation. Salt helps prevent spoilage by suppressing the bad bacteria, which is intolerant to salt, while simultaneously encouraging the growth of the beneficial bacteria (LAB). 

Salt also helps draw out the excess water from the vegetable, breaks down the cellular walls and penetrates the vegetable, thereby seasoning it. This will help the kimchi achieve a firm, pliable, crunchy texture (It also helps the seasoning to better adhere to the vegetable during the assembly).

Further, LABs require an anaerobic environment to thrive, which is why when we make kimchi we try to minimize the oxygen in the container by packing down the vegetables to minimize air gaps between the contents. The other important thing to do, when packing and fermenting, is to keep the contents submerged under the liquid line to prevent contact with the oxygen above the surface, to prevent surface mold. As fermentation kicks in, carbon dioxide is produced replacing the remainder of the oxygen, reinforcing the anaerobic habitat. Therefore, as you leave out the newly made kimchi on your countertop to ferment, you will notice the contents and liquid pushing up, open the jar and press the contents down, to keep submerged below the liquid.

The group of LAB microorganisms involved in fermentation is diverse and each LAB has its function and characteristics that shine at different stages of fermentation and under a range of conditions. The essential goal for LAB is to produce acid, each producing different amounts and types that allow subsequent LABs to come, play, and fulfill their tasks. Over time, as the acidity increases and the pH levels drop, it creates an inhospitable environment for harmful micro-organisms to survive. For humans consuming the ferment, well, things are considerably more favorable.

Signs of fermentation:

• tiny bubbles in the liquid

• vegetables pushing up from the gas buildup

• fermenting odor

At this point, you can move the kimchi into the fridge. Make sure to press down on the kimchi to keep the contents below the liquid line, tighten the lid and place it in cold storage. It will continue to ferment in the cold environment but at a slower pace, deepening the flavors; the slower the pace, the better the quality of the kimchi.

Salt and temperature affect fermentation significantly: Less salt and/or warmer temperatures speeds up the fermentation. 

• To ensure the quality of your kimchi and prevent mold, use a minimum salinity of 2%. (Some home fermenters may choose 1.5% but any lower will affect the crispness & crunchiness of your vegetables and increase potential for mold.)

• To maintain a crispier firm texture, avoid fermenting in higher temperatures which can turn your kimchi mushy. Ideal ambient temperature range, to kick start the fermentation, is between 65-72°F. In warmer temperatures, you will see the signs of fermentation sooner than in cooler temperatures; ie. summer vs winter.

Other factors that affect fermentation:

• denseness of vegetables

• water content

• size of vegetable.

We encourage you to use on-hand produce, eat seasonal/local and experiment. Find that sweet spot of fermentation that you enjoy as you curate your own kimchi. Use up your fresh odds & ends and help prevent food waste in the home, keep more money in your pocket, while promoting health through a traditional practice that fosters real food & real eating.

Food waste is a serious issue in this country, we encourage people to get creative with kimchi, tackle food waste by practicing root-to-fruit eating. Kimchi can be made with any type of produce and all of its parts, it’s why Korea has over 200 varieties of kimchi.

Let’s end food waste. Preserve through kimchi, zero waste through kimchi. Value the food grown for us by using up every bit.

Use up today’s odds & ends or excess harvest for tomorrow’s healthy diverse meals. Ferments pay back with loads of nutrition & benefits with minimal input.

Good for the gut, plate & planet.

Enjoy and keep us posted! We love hearing from our community of yummy creators spreading the love of kimchi.