@article{oai:teapot.lib.ocha.ac.jp:00035156, author = {稻垣, 長典 and Inagaki, Choten}, journal = {お茶の水女子大學自然科學報告}, month = {Nov}, note = {application/pdf, 紀要論文, The author has isolated a newly crystalline bitter substance from Citrus Natsudaidai (so-called Natsumikan) which has the composition of C_<24>H_<32>O_8. The chemical and physical nature of this bitter substance has been studied. The crystal of this substance obtained by crystallization from 95% alcohol or acetone melts at 274-275°. Extraction of the crystalline substance The exocarp and endocarp of Citrus Natsudaidai are extracted with 65-70% alcohol, and after the solvent has been distilled off, the residue is taken up in water and the impurities are removed by lead acetate solution. After the excess of lead has been removed by hydrogen sulfide, the solution is concentrated to obtain beautiful sexangle plate crystals. It is easily soluble in chloroform and acetone. It is soluble in warm ethyl alcohol, butyl alcohol and benzol, but is difficultly soluble in cold water, ether and petroleum ether. [table] It has reducing property, but does not give color reactions toward HCl and metallic Mg. It has color reaction by Molisch's and Naumann's tests. Its solution has bitterness free taste at above pH 4.6 and the bitte\ r crystals are easily soluble in chloroform and acetone and are absorbed with bentonite or Japanese acidic clay. Natsumikan Juice, which has bitterness-free taste and contains vitamin C, is prepared by amyl-alcohol treatment or bentonite treatment (added 5-10%, stirring for 30 minutes).}, pages = {133--137}, title = {夏みかんより新苦味物質の単離 : 附 ゼタミンC含有苦味除去果汁について}, volume = {2}, year = {1951} }