摘要：In this study sugar beet varieties (Evita, T.Ş. Poly. Gisela, Adonis and Agra) grown in the fields of the Sugar Research Institute (Turkish Sugar factories Corporation, Ankara) were tested for polyphenoloxidase (PPO) activity. The PPO enzyme activity was measured by an indirect method by using catechol as substrate. Slope of the absorbance-time graph was taken as the total enzyme activity. Some of the sugar beet varieties (Evita, T.Ş. Poly) had considerably higher average PPO activity and the variation of enzyme activity among the samples of the same cultivar was wide. However Adonis variety had lower values both in terms of average PPO activity and standard deviation. In Whole Sugar production polyphenoloxidases in beet deteriorate color of the product. Therefore, PPO is inactivated with steam at the first stage of production. Such varieties with lower PPO activity can be used advantageously in the Whole Sugar production in order to improve the color of the final product.
