HARMFUL NITROGEN AS A CRITERION OF BEET Q UALITY

Harmful nitrogen represents the soluble nitrogen of sugar beet which c annot be eliminated during traditional juice purification (e.g. total nitrogen in thick juice). For this reason harmful nitrogen is an impor tant criterion of beet quality. Using the recently developed pyro-chem iluminescence method harmful nitrogen can be determined in beet extrac ts clarified with aluminium sulphate as aluminum sulphate soluble nitr ogen (AlN). In a first overview the harmful nitrogen content of sugar beet from a variety- and nitrogen fertilizer trial is presented. Harmf ul nitrogen, together with other beet constituents, is subsequently us ed for quality assessment after the presently applied quality criteria . In contrast to the usual amino-N analyses harmful nitrogen determina tions by means of aluminum sulphate soluble nitrogen (AlN) will take i nto consideration this most important N-fraction of sugar beet in qual ity assessment and breeding for low nitrogen sugar beet varieties with sufficient alkalinity reserves.