RESUMO
A strategy to optimize biotechnological process design is illustrated for the production of fructose-rich syrups via enzymatic hydrolysis of agave fructo-oligosaccharides. The optimization process includes ecological studies from natural fermentations leading to the selection of a strain with capacity for inulinase synthesis, and variable optimization for the synthesis, and enzymatic hydrolysis using the response surface methodology. The results lead to the selection of Kluyveromyces marxianus , endogenous strains isolated from aguamiel (natural fermented sugary sap from agave plants), as the main strain with high capacity for enzyme synthesis with inulinase activity. Production optimization at bioreactor level revealed that operation at 30.6 degrees C, 152 rpm, 1.3 VVM of aeration, and pH 6.3 leads to maximum inulinase synthesis, whereas 31 degrees C, 50 rpm, and pH 6.2 leads to maximum hydrolysis of agave fructo-oligosaccharides. HPLC analysis of the fructose-rich syrups obtained at these optimal conditions showed an average composition of 95% of fructose and 5% of glucose and the absence of sucrose. The analysis also revealed that the syrups are free of residues and toxic compounds, an undesirable occurrence often present when traditional methods based on thermal or acid hydrolysis are applied for their obtainment. Therefore, the product may be suitable for use as additive in many applications in the food and beverage industries.
Assuntos
Agave/química , Biotecnologia/métodos , Aditivos Alimentares/química , Frutose/análise , Proteínas Fúngicas/metabolismo , Oligossacarídeos/química , Reatores Biológicos/microbiologia , Fermentação , Hidrólise , Kluyveromyces/enzimologia , Kluyveromyces/metabolismoRESUMO
Enzymatic treatments using noncommercial enzymes as a means to the improve the extraction of carotenoids and capsaicinoids from chili fruits are explored in this study. The results show that it is possible to obtain chili fruit powder with a higher concentration of both capsaicinoids and carotenoids than previously reported for similar processes. Furthermore, extraction yields above 96% for carotenoids and 85% for capsaicinoids as separate fractions can be achieved using a sequential and selective two-stage extraction. Evidence is presented demonstrating that the content and extraction yield depend directly on the extent of the enzymatic hydrolysis of chili cell walls, and higher yields are obtained when the sample is completely hydrolyzed. The enzymatic treatment described here is a promising alternative to current industrial practices, and it improves the extraction of carotenoids and capsaicinoids from chili fruits.