@article{oai:ir.kagoshima-u.ac.jp:00010534,
 author = {越智, 通秋 and 大城, 善太郎},
 journal = {鹿児島大学水産学部紀要=Memoirs of Faculty of Fisheries Kagoshima University},
 month = {2016-10-28},
 note = {Simplified method for colorimetric determination of gelatine in food and non-
food through the well-known Sakaguchi's reaction was investigated. The separation and determination of gelatine in the presence of large amount of other high molecular nitrogenous compound was achieved promptly by the following  procedure  : To 20cc. of test solution was added 5 cc of precipitant mixture  (  20% trichlo-racetic acid 1  :  25% Pb-acetate  1)  , and 5 cc. of 15% potassium nitrate, and its solution was filtered after being allowed to stand for 5 minutes. Then,  5  cc. of 2N sulfuric acid was added to  15  cc. of the filtrate to remove Pb-, and it was filtered after 5 minutes. Five cc of the filtrate was transferred into 15 cc. centrifuge tube, and added 1 cc of  10% sodium ortho phosphate di H  (NaH2PO4. 2H20) and  1  cc of  10% Na-tungstate to precipitate gelatine, the mixture was allowed to stand for 5 minutes, and then centrifuged for 5 minutes at 2000 R.P.M, and this supernatant liguid was siphoned off. The precipitate was washed 3 times with 5 cc. of N/5 sulfuric acid containing 5 % sodium chloride. The precipitate was dissolved in 6 cc of 5% sodium hydroxide, and was cooled in a ice-bath for 15 minutes. Then, 1 cc of ice-cold a-naphtol and 0.2 cc of ice-cold sodium hypobromite were added to the above solution. After 15 to 20 seconds, 1 cc of 40 % urea was added. The color developed almost immediately, but approximately 1 minute was required for maximum color  development. The optical density of the solution against water was  'read at 500 mμ. The determination of gelatine in certain materials by this method was possible to be made in 40 to 60 minutes.},
 pages = {71--77},
 title = {ゼラチンの比色定量},
 volume = {4},
 year = {}
}