How to use seaweed.

If you have never cooked with seaweed, start here. The basics: how to rehydrate it, which format to use for what, how much to add and how to store it.

The rule that sums it up: cold water and a few minutes. The umami does the rest.

The plant

Each format comes from a different part of wakame (Undaria pinnatifida). Knowing the plant helps you choose what to use.

Drawing of a whole wakame plant: blade, midrib, sporophyll and holdfast.

Blade: The leaf. Dried whole it is the whole leaf; without the midrib and flaked, the flakes.
Midrib: The central rib, thicker and crunchy. The most mineral part.
Sporophyll: The fertile frill at the base. This is mekabu.
Holdfast: What anchors it to the rock. Not eaten.

The key move: rehydrating

Dried seaweed rehydrates in cold water (never hot, which turns it slimy and ruins the texture). It unfolds in a few minutes.

A bowl of water with a handful of dried seaweed next to it.

Whole leaf

4–10 min in cold water

It unfolds and turns silky; it grows about eight times. Drain without squeezing and cut with scissors.

Flakes

Not needed

Sprinkle it straight on; it absorbs the moisture of the dish. If you like, 3–4 min in cold water.

Powder

No rehydration

Blend it straight into liquids, doughs or salt mixes.

Mekabu

5–8 min in cold water

It turns silky, almost gelatinous.

Water is not always needed. Seaweed rehydrates in any liquid and takes on the flavour of whatever wets it. In a vinaigrette, ten minutes: it rehydrates and marinates in one step. In beaten egg, five minutes before the pan. In milk or cream, an hour in the fridge. In a hot broth it rehydrates on its own, in the bowl.

Keep the soaking water

Since the seaweed has no added salt, the soaking water is not thrown away. It comes out salty and mineral: a finished stock. A soup base, cooking liquid for rice, pulses or potatoes, water for bread dough. The less water you soak in, the more concentrated it gets. It keeps two days in the fridge and three months frozen in an ice tray.

The soaking water is poured from the bowl into a pot.

Dried wakame, dark and tight, next to the same seaweed rehydrated and unfolded. — Dried, it has a greenish tone. Rehydrated, it turns green, slightly brown.

By format

Whole leaf

The whole dried leaf, minimally processed.

Soups, salads, long broths.

Flakes

Leaf only, no midrib, in flakes.

Sprinkling over eggs, rice, salads, doughs.

Powder

Whole seaweed finely milled.

Smoothies, baking, seaweed salt, thickening broths.

Mekabu

The wakame sporophyll: silky and mineral.

Soups and salads where you want texture.

Which format for what

A soup or salad

Whole leaf

To sprinkle on a dish

Flakes

To add to a smoothie, dough or salt

Powder

A silky texture

Mekabu

How much to use

As a starting point: a tablespoon of flakes or about 10 g of dried whole leaf per serving. From there, add to taste: in soups, salads and rice, seaweed can be the main ingredient.

In the kitchen

It salts without a salt shaker: lower the salt in the dish before adding it. It brings a saline, mineral depth that is not a fishy taste, a firm texture between leaf and cartilage, and some body to liquids.

Rehydrated and raw, it goes into salads or quick pickles. Dried, it cooks with the rice and rehydrates in the pot. Dried with oil, fried or in a hot oven, it becomes a chip. Ground in a grinder, it is table salt with flavour. And the soaking water makes the stock. It can also be eaten as is, dried, straight from the bag.

The nutritional values for this species come from scientific literature. We have not analysed this batch yet. When we do, it will be published.

Storage

Dried seaweed lasts a long time if kept dry: store it in an airtight container, in a cool dark place, away from moisture. Once rehydrated, use it the same day.

Tips & common mistakes

Cold water, never hot: heat turns it slimy and ruins the texture.
The umami is intense: taste the dish and add seaweed to your liking.
Keep it dry and airtight; moisture is its enemy.
If it over-hydrates, drain it well before using.

The seaweeds

Wakame

Mild, versatile, green. The easiest one to start with.

Luche

Red, sweet and delicate. For rice, fish, furikake.

Mekabu

The fertile base of wakame: silky, mineral, rich in fucoidan.

From the sea to the bag

Undaria reached Puerto Madryn in 1992, in the ballast water of a ship from the Mediterranean. A diver found it on the pier pilings. Nobody had seen it in Argentina before. Today there are a thousand kilometres of coast with it.

The cycle

It is harvested between August and October, while the seaweed is young. The sea lets us dive about fifteen days a month. In summer all the seaweed dies and detaches. In July a new cohort grows back.

The forest

It grows down to fifteen metres. The best quality is at three to four metres: that is where we harvest.

The cut

We free-dive or use tanks, and cut by knife. We cut below the sporophyll: that plant does not grow back and does not release the spores it would have released until December. Our harvest protocol limits the reproductive capacity of the species without affecting the ecosystem.

Drying

Seaweed hung in rows on a rack to air-dry.

The wakame you find in shops today is blanched and salted. This one is not. It is rinsed in fresh water and hung. It dries in the cold Patagonian air for four to six days, using no energy. There is no backup: if humid days come, it takes longer to dry.

Depth: 3–4 m
Bycatch species: under 0.5%
Harvested per 1 kg of dried wakame: 13 kg

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