It is difficult to imagine a healthy diet without fish - a source of easily digestible proteins and fatty acids. Where does this unforgettable “aroma” come from and why does it maintain such unshakable durability?
What smells like fish?
Anyone who has ever fished with his own hands knows that a fresh catch smells of the sea and algae or mud and green leaves (if we are talking about the scaly inhabitants of rivers and lakes). An unpleasant scent appears at the stage of autolysis - enzymatic cleavage of trimethylamine oxide (TMAO), which is part of the tissues. The content of this organic compound in the meat of marine fish is 90-1080 mg%, freshwater - 3–95 mg%.
TMAO plays the role of osmolite - a substance that holds fluid with it. Thanks to trimethylamine oxide, fresh water, which is necessary to maintain the normal functioning of the body, does not leave the cells in the salt marine environment. In addition, TMAO contributes to the normal functioning of cells under conditions of high pressure at depth.
Trimethylamine oxide itself smells almost nothing. The characteristic fish smell is responsible for trimethylamine, which is formed during changes in the body as a result of fishing and, as a result, the decomposition of TMAO. This “fragrant” volatile substance exhibits amazing durability, quickly and permanently absorbed into wood, fabric or skin.
Interesting fact: Trimethylamine is essentially a decomposition product.Therefore, the sense of smell of humans and animals has evolved to perceive this smell as something repulsive.
Which fish have no smell?
In mid-May, residents of the Northern capital celebrate a grand holiday - the smelt festival. When the elongated silver fish caught in the Neva River begins to be sold in the markets, a fragrance spreads ... fresh cucumber throughout the city. It is this smell that is inherent in the representative of the smelt family. A pleasant aroma lasts 2-3 days.
Ichthyologists explain this phenomenon by the presence of 2,6-nonadienal, an aldehyde contained in cucumber essential oil, in the mucus that covers the fish. And the fresh, cold waters of the Neva, washing the body of smelt from the salt of the Baltic Sea, are responsible for the intensity of the smell.
By the way, the fresh cucumber smell is inherent not only in the gastronomic attractions of St. Petersburg, but also in whitefish, capelin, cape and grayling. However, cucumber aldehyde erodes from their mucus much faster.
How to get rid of the smell of fish?
The good news: an unpleasant odor appears long before the fish meat becomes completely unfit for human consumption. And to get rid of the annoying "fragrance", you need to remember that the amines to which trimethylamine belongs are successfully neutralized by acids.
Before cooking, fish should be washed thoroughly under a stream of cold water. Then for one hour place it in acidified water with vinegar or lemon juice, adding pepper and chopped bay leaf. Salt the dish immediately before frying or baking.
A fish scent will leave dishes and kitchen utensils if you wipe them with dry mustard, wet baking soda or the juice of one lemon before washing. A solution of vinegar fights the odor remaining on the skin of the hands. The role of a neutralizer is played by orange essential oil added to cool water.
The fish owes a strong and sharp “amber” to trimethylamine oxide - a compound necessary for regulating osmotic pressure in cells. This organic substance in itself is odorless - it appears after the death of fish, when, under the influence of enzymes and bacteria, trimethylamine oxide decomposes to trimethylamine, which emits an unbearable “aroma” of rot. And its resistance is explained by the usual property of all odorous amines to easily soak the skin, wood and fabrics.
