Abstract
It is said that the lizard fish muscle being able to make a strong jelly while it keeps fresh, may be decreased in jelly-forming ability at a great rate after losing freshness. It is also accepted as true that the shark muscle seems, on the contrary, to be rather increased in this ability with decrease of its freshness. We have studied on the reasons for these influences.
In the present experiments, these fishes were both found to be decreased in jelly-forming ability with fall of the freshness, and be recovered in its ability with the higher staleness. One of the rcasons for the decrease of this ability in the early stage of storage, seems to be due to the denaturation of the protein in these muscles, and its recovery in the later stage to be ascribed to the increase of alkalinity accompanying the rising of the pH value.
In the case of the lizard fish, its recovery stage of the jelly-forming ability is quite out of question, because in this stage the muscle will be so much putrefied that it is impossible to make the food products. It should be said therefore that the jelly-forming ability of the lizard fish is easily lost in the course of storage. And the rate of its loss was found to be very large.
In the shark muscle whose jelly-forming ability is recovered with its intense alkalinity in the early stage, it may be said that the muscle shows sometimes the strong jelly-forming ability with decreasing of the freshness.
