Avaliação do processo de fermentação alcoólica de suco de maçã obtido por liquefação enzimática

Abstract

The application of clean technology concept aims to optimize the extraction process in order to obtain maximum juice, to decrease loss and to manage the generated residue applicability. The use of enzymatic complexes, of cellulases and pectinases, during juice extraction process allows to modify physical-chemical characteristics of the products and to minimize residue generation. This work aimed to study the fermentative behavior of apple juice obtained through the use of clean technology concept, called enzymatic liquefaction. Process and liquefaction products characteristics were compared to extraction by pressing. An increase of 28.43% in total acidity, 28.6% in total nitrogen and 39.38% in phenolic compounds was found in the juice obtained by liquefaction. The pomace presented a decrease of 23.35% in pectine, an increase of 38.3% in ether extract and was not observed statistical difference for total alimentary fiber values. By using enzymatic liquefaction process was observed a decrease of 19% of humid residue, when compared to pressing process. The juices obtained by enzymatic liquefaction and pressing process were submitted for fermentation, in defined conditions of temperature and time, when was undertaken the analysis of biomass production kinetics, ethanol, flavor volatile compounds formation and the total sugar reductor consume. The superior alcohol sum for fermented obtained from liquefaction and pressing was 133.6mg.L-1 and 130.4mg.L-1, respectively. Methanol average levels, resulting from pectin desmetoxilation by pectinesterase activity were 486.24mg.L-1 for liquefaction process and 13.95mg.L-1 for pressing process.