Cooking with acids

When we cook food applying heat, we are modifying their molecular structure in order to make them more palatables and digestibles.
One of the effect of heat on food is protein denaturation, which are part of the muscles in meat and fish.
This denaturation makes meat softening and thus with a nicer texture to eat.

A similar protein denaturation, although weaker, can be achieved with acid marination. The effect is similar to a superficial weak boil, too weak for meat but enough for some fishes.

For instance, marinated fish in lemon juice is the base of the Peruvian “ceviche”.
Marinated anchovies in vinegar (together with garlic) is the base of the Spanish dish "boquerones en vinagre"
In Finland, we have something similar with salmon in mustard (and dill), where the vinegar of the mustard "cooks" the salmon.

The most commons acids in kitchen are lemon juice (citric acid), vinager, (acetic acid) and red wine (tartaric acid). Lemon juice can be easily sustituted by citric acid solution.

Beef-carpaccio recipe:

Beef frozen tenderloin is cut in thin stripes with either a mandoline or a very shrap knife. The stripes are hold in a plate and marinated with lemon juice for about 30 min. in refrigerator.

It is served with a splash of extra virgin olive oil and some parmesan small chips. High quality olive oil with herbs gives an extra aroma to good meat.
You can decore it with rucola leafs.