Publication Date:
1916-09-01
Description:
Gill in 1871 first pointed out that when an excess of basic lead acetate is added to a solution of invert sugar the negative rotation of the latter is greatly reduced owing to the formation of a soluble lead compound of laevulose. If sufficient lead solution is added the negative rotation may become a positive one; thus in one experiment quoted by Gill a negative reading of – 28° was transformed into a positive value of + 57°. The change of rotation was not, however, permanent and on removing the lead or on acidifying the solution the original rotatory power was restored. The change of rotation was attributed to an effect of the lead on the laevulose only; a solution of dextrose was practically unaffected by the presence of basic lead acetate. Since Gill's paper the effect of basic lead acetate as a source of error in sugar analysis has been the subject of numerous papers especially by Pellet, Svoboda, Edson, Prinsen Geerligs, Watts and Tempany and Eynon.
Print ISSN:
0021-8596
Electronic ISSN:
1469-5146
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
