Abstract
On the basis of the results obtained from the previous experiments the author has made the assumptions as follows:
(1) Volatile acids in fish meat may consist of two kinds, one being free acids, and the other bound acids.
(2) The second distillation ratio of the acids from fresh meat of fish exceeds 100 percent because the bound acids are greater than the free acids in amount so that few acids could be obtained in the first distillation.
(3) However, the amount of the free acids increase, while the bound acids decreasing, in response of deterioration of the meat. Such fluctuations in the acids seem to account for the second distillation ratio lowering below 100 percent in case of a spoiled meat.
In order to prove the above assumptions the following experiments have been carried out.
Prepare three kinds of samples from fresh meat of fish; minced meat, its water exudation, and a protein-free solution by treating the sample with 20% sodium tungstate. The similar group of the samples is prepared from the spoiled meat of a fish. Apply steam distillation to each sample.
It was found as a result that the free acids were almost removed dy exudation, for volatile acids contained in the residue of the exudation were measured but little.
When free volatile acids were wrapped as a reagent together with gelatin, they were formed into bound acids to some extent, as the results are shown in Tables 1 to 3.
