Hwangtae-guk (Freeze-Dried Pollock Soup)

Name: Hwangtae-guk (Freeze-Dried Pollock Soup)
Prep time: 20 min
Cook time: 35 min
Total time: 55 min
Yield: 3 servings
Cuisine: Korean
Ingredients: 60 g shredded hwangtae; 1.5 L water; 150 g daikon; 1 piece kombu; 1 tbsp toasted sesame oil; 1 tbsp perilla oil; 1 tbsp garlic; 1 tbsp soup soy sauce; 1 tsp salted shrimp; 2 eggs; 1 spring onion; 150 g tofu; 1 pinch black pepper

A Gangwon hangover soup made from pollock that has been frozen and thawed all winter long. This site’s freezing guide opens with "ice crystals tear cells" and tells you to freeze as fast as you can, because slow freezing grows large crystals that rupture cell walls and let the moisture out on thawing — dry food sitting in a puddle. Hwangtae is that failure carried out about ninety times over three months, on purpose. What is left is a sponge full of holes, and rehydrated it holds more liquid than the fresh fish ever did.

Steps

Soak the shredded hwangtae in cold water for five minutes only and lift it out — longer and the flavour goes into the water. Keep that water for the broth. Squeeze the fish out by hand.
⏲ 5 min
If you have a whole one, beat it with a rolling pin to loosen the grain, pull off the head, bones and fins, and tear it into strips. The beating is part of the cooking — the fibres have to split before broth can get inside them.
⏲ 10 min
Heat the sesame and perilla oil in a pot and fry the squeezed fish 2-3 minutes. Frying the dried fish in fat before any liquid goes in is what gives the broth its nuttiness. Add the garlic for another 30 seconds.
⏲ 3 min
Add 1.5L of water with the daikon and the kombu and bring it up hard. Lift the kombu out just before it boils — boiled, it goes slippery and bitter.
⏲ 8 min
Twenty minutes at a medium-low simmer. When the broth turns cloudy and milky it has drawn properly. Leave the lid slightly ajar.
⏲ 20 min
Season with soup soy sauce and salted shrimp, adding the tofu now if you are using it. When it returns to the boil, turn the heat down and pour the beaten egg in a thin stream. Do not stir for ten seconds — stirred, it disperses and clouds the broth.
⏲ 3 min
Add the spring onion for 30 seconds, grind over pepper and take it off. Serve in an earthenware bowl.
⏲ 1 min

Tips & Variations

Variations

Bugeo-guk. Made with bugeo, pollock simply air-dried without the freeze-thaw cycling. The flesh swells less and the broth is a little thinner. ko.wikipedia keeps the two names apart.
With bean sprouts. Outside Gangwon many households add them, which brings in the clean edge of Kongnamul-guk.
Sesame oil only. Perilla oil is not essential; without it the aroma is lighter.
Clear. Some skip the egg entirely and keep it clear with only daikon and spring onion.
Grilled or steamed. The same fish is also painted with a seasoning paste and grilled or steamed rather than made into soup.

Tips

The ingredient is the freezing guide's failure, repeated on purpose. Freezing and Thawing opens with "ice crystals tear cells": freeze slowly and the crystals grow large, rupture cell walls, and on thawing the moisture escapes through those holes — so freeze as fast as you can. Hwangtae is the exact opposite. On the drying racks of Daegwallyeong it freezes every night and thaws every day for three months, about ninety times. The bigger the crystals and the more holes, the better the hwangtae.
What is left is a sponge. Riddled with holes, the flesh rehydrates to hold more liquid than the fresh fish ever did. That is why the broth goes into the fish rather than sitting on it, and why a mouthful releases broth when you bite it.
Read it beside Polbo á Feira. That freezes an octopus once, to break down connective tissue — the aim is tenderness and the result is still a wet octopus. Hwangtae does the same thing ninety times while drying — the aim is preservation and the result is a dry sponge. Pelmeni uses freezing as a production step. Same ice, three different jobs.
Beating it is cooking, not prep. The muscle bundles only split while the fish is dry. Skip it and the outside rehydrates while the inside stays stiff.
Five minutes of soaking, no more. Longer and the savour leaves for the water. And do not throw that water away — the same reason dried shiitake and dried shrimp are on the "use it" side in Soaking.
Fry it in fat first. Frying the dry flesh before any liquid goes in is half the colour and half the nuttiness of the broth. Skip the order and you get a bland fish soup.
Pour the egg and count, do not stir. A thin stream, then ten seconds untouched. Stirred, it disperses and the broth goes muddy.
Cloudy broth is the sign. Unlike Seolleongtang, where it comes out of bones, here it came out of the inside of the sponge.