TRATAMENTO ENZIMáTICO DA POLPA DE UVA NO PROCESSO DE PRODU O DE SUCO DE UVA

This work aims to investigate the best conditions for an enzymatic treatment of grape juice. Twoenzymes of type pectinolyase (Novozym 33095) and polygalacturonase (Ultrazym AFP L) were tested inorder to improve the quality of the pulp of grape before a membrane separation process. A series of enzymatictreatments was performed regarding properly ranges of enzymatic concentrations (50-100 mgL-1), treatmenttemperatures (35 and 45 oC) and process times (0-90 min.). Essentially a set of physico-chemical parameterssuch as total acidity, soluble solids, color and turbidity was considered for the assignment of grape pulpquality and choose of the enzyme as well as get its best experimental condition. From a statistical analysisfor both tested enzymes, an enzymatic treatment based on the Novozym 33095 has improved the grapepulp quality when this process is performed at an enzymatic concentration of 50 mg L-1, 35 °C temperatureand 15 min. of treatment time. Under this experimental condition, a significant reduction on the turbidity,suspended solids and pectin in grape was achieved, resulting in a grape juice with a minimum amount ofpulp, more clear and transparent.