WHY SALMON ARE PINK

Southland Times, Issue 19625, 21 September 1922, Page 7

WHY SALMON ARE PINK

A PUZZLE FOR NATURALISTS. Men of science were long puzzled to know why the various salmon and trout, have red or pink flesh. Now they believe that the colour comes from the food they eat (observes the Youth’s Companion). All of the salmon family arc particularly fond of shellfish; and trout eagerly feed on freshwater shrimp. It is well known that when lobsters, prawns, and shrimp are cooked the flesh turns pink; similarly the process of digestion turns shellfish pink. When a shrimp is found in the stomach of a salmon or a trout the gastric juices of the fish have turned it almost as red or pink a? if it had been boiled. Therefore, even if we had no definite proof, wc might believe that the colour of the flesh of salmon and trout results from the considerable quantities of various small shellfish that the fishes eat. But there is definite proof. Several years ago Professor Leger, of the Piscicultural Laboratory at Grenoble, France, made experiments with trout to determine what gave their flesh its colour. He separated the eggs from one trout info two lots, and hatched them in different troughs. He fed one Jot of young fish exclusively on freshwater shrimp's; to the other lot he gave no shrimps whatever. At the end of the second year the trout that had fed on shrimps had salmon-coloured flesh, but the flesh of the other trout- was perfectly white. But someone may ask, why is the flesh of shellfish red or pink? That is a hard question to answer. Perhaps the colour comes from the food the shellfish cat.*