Sugarcane quality by X-ray spectrometry in the field

The quality of sugarcane growing in the field can be estimated by portable energy dispersive X-ray fluorescence with a handheld instrument, helping to judge when best to harvest a particular crop, say Brazilian scientists. Fábio Luiz Melquiades from the Universidade Estadual do Centro-Oeste in Guarapuava, and coresearchers, measured the sucrose concentration, fibre content and degree of polarisation in the growing stems of 11 varieties of sugarcane, and compared them to the values for the leaf and for extracted juice.

Using two portable spectrometers, the data were processed by principal components analysis, as described in the Journal of Agricultural and Food Chemistry. With rapid preliminary cleaning of the test region on the stem using dry paper and a single 60-second irradiation, the results were equivalent to those from the juice and more accurate than those from the leaves. The data from the two instruments were equivalent, confirming that the use of portable equipment in the field is valid in real time.

Analysis in the field is more convenient and far less time consuming than analysis of the juice and many measurements can be taken quickly. The procedure will help farmers to decide when to cut the crop and will be invaluable for the alcohol and sugar industries.