Cucumber Kimchi (Oi-Sobagi)

Oi-sobagi is summer kimchi: crisp cucumbers cross-cut and stuffed with a garlicky gochugaru filling, given a short ferment, then chilled. It is a fresh, fast kimchi — bright and barely soured rather than deeply funky — and is meant to be eaten within a week while it is still snappy.

Ingredients

Cucumbers are dry-salted at 2% of cucumber weight, briefly, to firm them and draw a little water. The filling is a smaller version of the kimchi paste.

Ingredient	1 Jar (1 qt / 1 L)	1 Crock (2 L / ½ gal)
Kirby / Korean cucumbers, whole	700 g	1750 g
Non-iodized salt — for salting the cukes	14 g	35 g
Gochugaru (Korean chile flake)	20 g	50 g
Garlic, grated	12 g	30 g
Ginger, grated	4 g	10 g
Fish sauce	15 g	38 g
Korean radish or carrot, fine matchsticks	60 g	150 g
Garlic chives or scallion, 2 cm cut	40 g	100 g
Sugar	1 tsp (~4 g)	2½ tsp (~10 g)

Yield: about 750 g stuffed cucumbers per jar; about 1.9 kg per crock.

Calculated values

Value	Target
Cucumber salting (dry-salt % of cucumber)	2.0%
Working salinity, finished dish	~2%
Ferment temperature	18-22 °C / 64-72 °F
Time at that temperature	4-12 h (then refrigerate)
Eating window	best within 5-7 days, refrigerated
Cold storage / arrest	2-4 °C

Set the cucumber salting with the dry-salt calculator.

Readiness window

Oi-sobagi is a short ferment: a few hours at room temperature to start the lactic activity, then straight to the fridge. Held at 18-22 °C it is ready in 4-12 hours — taste at 4 h. It does not reach the deep sour of long-fermented napa kimchi, and it is best eaten within 5-7 days while crisp.

Done when: the filling smells lively and garlicky, the brine at the bottom is faintly tangy, and the cucumbers are still crunchy. Move to 2-4 °C to hold; the sourness builds slowly in the cold.

Method

Cut and salt the cucumbers

Trim the ends and cut each cucumber into 5-6 cm logs. Slit each log lengthwise into quarters, leaving 1 cm uncut at one end so it stays hinged. Toss with the salt and rest 30-60 minutes until pliable; they will weep a little water.

Rinse and drain

Rinse briefly under cold water and drain well, pressing gently. The cucumbers should bend without snapping.

Make the filling

Combine gochugaru, grated garlic and ginger, fish sauce, and sugar into a paste; fold in the radish/carrot matchsticks and chives. (For vegan, swap fish sauce for light soy or a kelp stock.)

Stuff the cucumbers

Wearing gloves, pry open each slit cucumber and pack the filling into the cuts. Set the stuffed logs upright in the jar.

Pack and rinse the bowl

Press the stuffed cucumbers into the vessel. Swirl 2-3 Tbsp water in the seasoning bowl and pour it over so the filling stays moist. Leave 2-3 cm headspace.

Brief ferment, then chill

Hold at 18-22 °C for 4-12 h, tasting at 4 h. When faintly tangy and aromatic, move to 2-4 °C and serve cold within the week.

Variations / mix-ins

Vegan: replace fish sauce with light soy sauce or a kombu stock.
Extra-crunch: add a few fine matchsticks of Korean radish to the filling.
No-stuff (quick mat-style): slice the cucumbers into coins and toss with the filling for an even faster, salad-like oi-muchim that you eat the same day.