Lightly brining fresh fish eggs firms their texture and turns them colorful and translucent. The result pops in your mouth and tastes of the sea. The salt levels called for here will produce a caviar that is seasoned like Japanese-style salmon roe (ikura) or what Russians call malossol (lightly salted). We learned about the hot water soaking method from Bonnie Morales’s book, Kachka.
Remove from very fresh fish as soon as possible:
Thoroughly rinse the sacs under cold water and refrigerate in a bowl. Place a grid-patterned wire cooling rack set over a large baking dish and fill a large bowl in the sink with piping-hot tap water. Transfer the sacs to the hot water and let them soften for 5 minutes. Drain the water. Place one of the sacs on the cooling rack with the exposed eggs facing down. Press down gently and move the sac back and forth on the cooling rack, letting the wire work the eggs free from the membrane. Discard the membrane and repeat with the other sacs. Rinse out the large bowl, fill with cold water, and transfer the eggs in the baking dish to the water. Stir the eggs around with your fingers, agitating them so that any lingering pieces of membrane are freed (they will float to the surface). Carefully pour off the water and any floating bits from the top, keeping the eggs in the bowl with your hand. Fill the bowl with more cold water, agitate, and repeat until the water is clear and there are no more floating bits. Drain the roe, measure their volume, and refrigerate.
For every 2 cups roe, whisk together in a large bowl until the salt has dissolved:
Add the roe to the brine and refrigerate for 1 hour. Strain the roe once more, discarding the brine, and let the roe drain, covered, overnight over the bowl.
The roe is now cured and ready to eat. Transfer to a glass jar and keep refrigerated for up to 5 days, or transfer to a zip-top freezer bag, seal with the air displacement method and freeze for up to 2 months.