COLORIMETRIC DETERMINATION OF THE CONTENTS OF TOTAL AND REDUCING SUGARS IN CEREALS

There are laboratory procedures of determination of the concentration of soluble and reducing sugars from one plant extract by colorimetric reactions with phenol in the medium of sulphuric acid and with hydrazide of the range of determination of total sugars is varying from 5 to 50 mug and reducing sugars from 1 to 10 mug in sample. Reproducibility of results between individual samplings is on the level of 8 % and is affected by standardization of laboratory processes and purity of chemicals. At the same time, there are presented concentrations of total, non-reducing (difference between total and reducing) and reducing sugars in aboveground part of winter wheat during vegetation of 1991. It was found out that the ratio between non-reducing and reducing sugars is changing during vegetation. This is higher prior to winter and in the generative phase and the lowest is in the period of vegetative growth.