Resumo

GONZALEZ-ALEJO, Fanny Adabel; BARAJAS-FERNANDEZ, Juan  e  GARCIA-ALAMILLA, Pedro. Extraction of soluble compounds from cocoa shell with supercritical CO₂ . A methilxantines and fat case. CienciaUAT [online]. 2019, vol.13, n.2, pp.128-140. ISSN 2007-7858.  https://doi.org/10.29059/cienciauat.v13i2.1073.

Supercritical extraction is an effective technique for separating various compounds from natural matrices due to the properties from solvents, such as CO2, in supercritical state. In the present work, the supercritical extraction of theobromine, caffeine and fat from cocoa shell was carried out with supercritical CO2. A 22 design with 5 central points was proposed, with static operation conditions, having pressure (2 000 psi to 6 000 psi) and extraction temperature (318 K to 333 K) as study factors. The residues were analyzed in the extraction chamber to evaluate the removal and residual percentages of fat, caffeine and theobromine, respectively. The results showed a yield between 1.72 % to 9.57 %, with a removal rate for fat and caffeine of 61.31 % to 94.54 % and 38.52 % to 78.38 %, respectively. The theobromine was retained in the shell powder with a residual ratio greater than 90 %. The effects of temperature and pressure for fat were predicted through a first-order polynomial with interaction effects, but not for caffeine or theobromine. The extraction method was efficient to remove fat and caffeine, leaving a residue powder in the extraction chamber considered as high in functional compounds.

Palavras-chave : theobromine; caffeine; fat; supercritical extraction; cocoa shell.