(1) The muscle proteins of some hens, various fishes and certain animals were prepared as samples for the purpose of studying what changes take place in the muscle proteins at the time of canning meats under pressure and heating. The materials were sealed in glass-tubes and heated at 130–140°C. for one hour, and changes of materials were studied. (2) The hydrogen ion concentration of all of the proteins showed a tendency to approach toward the neutral point. (3) About 20 per cent. of the protein nitrogen was transformed by heating to peptone, peptide, and amino acid nitrogens. The formation of soluble nitrogen compounds, such as these, is considered to cause a speedy putrefaction of contents of an opened can. (4) As the results of elementary analyses of carbon, hydrogen, nitrogen, sulphur and phosphorus, it was found that the quantities of nitrogen and sulphur contained in the proteins generally decreased by heating, and the changes were more marked the higher the values of pH. There was no appreciable change in phosphorus when the solution was neutral, but its amount decreased when the solution was acidic or alkaline, and hence the percentage of carbon increased. (5) The quantities of NH3 and H2S generated by heating were greater in proportion to the values of pH of the solutions. This result explains the fact that, when the tin of cans are bad and the pH of the contents is high, the contents of the can deteriorate more readily and the colour changes to black. (6) As the results of the analyses of the proteins by the Van Slyke method, the decrease of the total nitrogen, ammonia nitrogen and cystine nitrogen and the increase of melanine nitrogen were detected especially when the pH value increased. The quantities of cystine, arginine, histidine and lysine contained in the materials showed a tendency of decrease in all three cases and the same tendencies were very remarkable on cystine at the higher value of pH and on lysine at the lower. (7) Tryptophane by the May-Rose method and tyrosine by the Folin-Denis method were quantitatively analyzed, and the decreases of these substances by heating were very insignificant. (8)The test for proline was made by the Fisher-Bechner method, but no decomposition by heating was observed. (9) Cysteine and cystine were analyzed quantitatively by the Okuda-Katai method, and it was found that a part of any one of these acids always changed to the other acid by heating. But the sum of the two always decreased, and the decomposition of both of these acids was remarkable at the higher value of pH, and the decomposition of cysteine was greater than that of cystine. (10) A part of the protein-sulphur changed by heating to hydrogen sulphide, other sulphides, sulphuric acid and soluble organic sulphur, and the quantities of these substances generated were greater at the higher pH of the solutions, as in the case of the decompositions of cysteine and cystine.
(1)The Raman spectra of methyl phenylacetate, ethyl phenylacetate, ethyl phenylpropionate, ethyl cinnamate, iso-propyl cinnamate, dimethyl phthalate, diethyl phthalate, methyl salicylate, ethyl salicylate and methyl phenyl carbinol were studied. (2) The constitutive influences exerted on the C–H of the benzene ring were observed. It was found that the carbon with the double bond (Remark: Graphics omitted.) attached to the benzene ring (Remark: Graphics omitted.), such as in the case of C6H5·CO·O·R and C6H5·CH=CH·CO·O·R gave the higher frequency (Δν=3070) than that (Δν=3055) in the case of C6H5·CH2·(Remark: Graphics omitted.)O–R and other compounds of the type, C6H5·CH2–X which have no carbon with double bond directly attached to the benzene ring. (3) The constitutive influences exerted on the carbonyl group were observed. (4) Disappearance of 615 cm.−1 in diderivatives and appearance of 560 cm.−1 in salicylates, o-kresyl acetate, o-kresyl benzoate and cinnamate were observed. (5) Estimation of the valency frequencies of the (Remark: Graphics omitted.) linkage was confirmed.