摘要：Beans occupy an important place in the diet of Brazilian people but their use by phenylketonurics is forbidden. In this way, this study aimed at reducing Phenylalanine (Phe) content from protein beans using activated carbon as Phe adsorbent. The effect of some parameters was evaluated, such as initial pH, enzyme: substrate ratio, temperature, type of protease and protein: activated carbon ratio. The efficiency of Phe removal was assessed by second derivative spectrophotometry. The results showed that the percentage of Phe removal varied from 25.4 to 87.9% and the final Phe content from 433.7 to 2679.8 mg Phe 100 g-1 hydrolysate. The action of a protease from Papaya carica gave rise to the highest percentage of Phe removal (81.5%) and the best values for enzyme: substrate ratio, protein:activated carbon ratio and temperature were 10:100, 1:88 and 50°C, respectively. The pH of 8.4 was chosen as the best one, since no adjustment was needed for initiating the hydrolytic reaction. The conditions used in this work were appropriate for obtaining low-Phe beans.
