0023-6152

AA00697606

23720

査読無

0023-6152

AA00697606

This study was undertaken purely from processing point of view, hence the conclusions made were also, which better fitted in the process, judged by the experience. It was found that unleached peel can not be dried satisfactorily because of its sticky nature and development of undesirable dark reddish brown color, and that cold leaching seemed more practical than hot leaching when compared on the basis of economy and merits in return. Quality of pectin in citrus material was adversely affected by drying temperature. whereas. moisture contents of the dry pomace and the temperature of peel in its final stage of drying controlled the quality of pectin in the pomace. Yields of cold and hot leached pomace were 11.2 % and 9.6 % respectively and that 7-10 % moisture contained pomace did not show any promising undesirable change during one year of storage when packed in the polythene bags and kept in a dry place. Total extractable pectin yield increased about 3 % and 5 % by cold and hot leaching respectively (due to concentration of pectin in the peel by leaching out other soluble solids), this difference was more promising when yield calculated on qualitative basis. An extract suitable for Cu^<2+> precipitation (0.50-o. 55 % pectin) was obtained by extracting one part weight of pomace with 40 parts of 0.13 % HCl solution (extract pH 1.7) for 45 minutes at 95℃. Best Cu-pectin precipitates were obtained when 20mg of Cu^<2+> as CuCl_2 was added in 100 ml of 0.50-o. 55% pectin contained extract and then pH was adjusted at 2.8 with conc. NH_4OH, after cooling the mixture to about 20℃.