Minoru Akiba

On the Streaming Birefringence Observed in the Meat Extracts of Sea Cucumber (Stichopus japonicus SELENKA)-III

The substance which shows streaming birefringence in the water-extracted solution of sea cucumber meat is considered to be the suspended fibrous matter of collagen fiber, rather than to be some dissolved proteins. On the contrary, in the case of squid meat, substance which shows streaming birefringence is suggested by electrophoretic examination to be a dissolved protein (viz., myosins). The phenomenon of streaming birefringence in the extract of ?? ea cucumber meat should be discussed from the histological characteristics.

Studise on the Manufacture of Gyomeso (Fermented Fish Paste) II. The Chemical Changes of the Fish Meat Protein during the Ripening of Gyomiso

(1) The decomposition of fish meat protein is the most active from the 7th day to the 13th day after mixing the raw materials. From the 14th day the rate of the decomposition slows down. (2) The hydrogen ion concentration of the mixture decreased in the earlier time after the mixing, but increased slowly at the end of the ripening. (3) The quantity of non-protein nitrogen increased rapidly from the 7th day to the 13th day but thereafter remained static. (4) The change of the quantity of amino acid nitrogen, which constitutes the greater part of the non-protein nitrogen, was the same as (2). But the decreasing of the quantity of amino nitrogen at the end of the ripening of the mixture was due to the creation of ammonia from the amino acid. These changes can be explained by the change of the hpdyogen ion concentration of the mixture. (5) The ratio of the quantity of non-protein nitrogen and of amino acid nitrogen to the amount of total nitrogen was investigated. The ratio of non-protein nitrogen to the total nitrogen increased rapidly from the 13th day after the mixing, and thereafter the increase slowed down. The ratio of amino acid nitrogen to the total nitrogen showed the same tendency as in the case of the upper mentioned ratio. The ratio of amino acid nitrogen to the non-protein nitrogen showed also the same tendency as in the case of the upper mentioned ratio.