Aproveitamento do bagaço de abacaxi (Ananas comosus L. Merril) para produção biotecnológica de xilitol

• Autor(a) principal: Silva, Orlando de Oliveira
• Data de Publicação: 2011
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/440
• topic: Fermentação; Biomassa; Hidrólise; Edulcorante; Fermentation; Biomass; Hydrolysis; Sweetener; CNPQ::CIENCIAS AGRARIAS::CIENCIA E TECNOLOGIA DE ALIMENTOS

Pineapple bran from a juice agribusiness was collected and characterized by quantitative saccharification for the monomeric sugar contents, glucose (29.9%), xylose (27.63%), arabinose (5.48%), and lignin (15.1%), making up the fiber. Then it was used to obtain hemicellulosic hydrolyzate by dilute-acid hydrolysis. The condition of hydrolysis was determined by surface methodology, with collected data from tests in batch reactor, following spherical experimental design (23 + 13), considering the factors temperature (120 to 160 ºC), reaction time (20 to 40 minutes), and H2SO4 concentration (2 to 4%). The hydrolysis condition at 140 °C, 20 minutes, and acid 2% was selected as one of the best way to perform the pineapple bran hydrolysis in a pilot reactor (100 L). The hemicellulosic hydrolyzate was concentrated four times relative to its sugars initial content, detoxified by combined method with CaO and adsorption with activated charcoal. It was then characterized for the glucose contents (21.3 g L-1) and xylose plus fructose (64 g L-1), heat treated at 60°C for 120 minutes, supplemented with nutrients (NH4)2SO4 1 g L-1, MgSO4 7H2O 1.1 g L-1 and yeast extract 5 g L-1), and fermented in a bioreactor (Vmeio = 1.0 L, X0 = 1 g L-1, pH = 6.0, 30°C, 2.5 vvm, 200 rpm for 120 h) by Debaryomyces hansenii UFV-170, resulting in 28 g L-1 of xylitol, volumetric productivity of 0.24 g L-1 h-1, and μmáx equal to 0.034 h-1.Pineapple bran from juice agribusiness is a potential raw material for obtaining hemicellulosic hydrolyzate by dilute-acid hydrolysis and excellent substrate for xylitol production by fermentation with Debaryomyces hansenii UFV-170.