Grave-curing and pickling fish
There are two methods of preserving fish I like: grave-curing and pickling. In the old time, fishermen would dig a hole on the beach and bury their fresh catch in salt, to be dug up later for a meal. But for grave-curing a freezer bag is also okay.
To implement this kind of preservation technique (grave-curing), I use a salt-sugar cure that draws the natural liquid out of the fish to form a brine. The fish soaks in its own juices--it’s getting really savory and delicious as enzymes work to break down proteins into amino acids and fat into fatty acids-- and the high salt content discourages the growth of bad bacteria while encouraging the growth of lactobacillus. As the lactobacillus multiply in the cure, they produce lactic acid, lowering the pH of the fish (more acidic), and producing an even more beneficial environment for themselves, as well as further defending against the growth of other kinds of bacteria.
The amount of salt and sugar to use depends on the length of the cure and the kind of end product I am looking for. The more sugar the cure contains, the creamier the fish will be. If the fish is only being cured for a short time, the fish will be sweeter, because the lactobacillus will not have had enough time to consume the sugar in the cure. If the cure is longer, the lactobacillus will have consumed more of the sugar, and the fish will be more acidic. More salt means more water is drawn out of the fish, so it will be firmer and the pH level will be lower. Longer cures are more savory, because the lactobacillus will have broken down more of the protein and fat into amino acids and fatty acids.
For a pickle, I follow a short grave-curing process by submerging the fish with its savory brine into a solution of white vinegar and liquor. Both methods take a large quantity of aromatics. I like bay leaves, rainbow peppercorns, sea buckthorns, Jamaican scotch bonnet peppers, juniper berries, and lots of fresh dill. I also like coriander, cardamom, and caraway. The aromatics ferment along with the fish, resulting in an even more complex flavor. Both grave-cures and pickles should have plenty of red beets in them for color. The sugar in the beets also encourages lactobacillus growth, and as they ferment they will enrich the flavor of the fish.
The more time, the more savory the result. A good grave cure should go at least three weeks; a good pickle will result in a very firm fish, at least two weeks.