The effect of temperature, catalyst concentration (sodium hydroxide), alcohol molar ratio: oil and transesterification time on the yield of biodiesel obtained from cherimoya residue oil (Annona cherimola) was evaluated. A rotatable composite central design (DCCR) with 30 runs was used. The concentration of the catalyst and the molar ratio alcohol: transesterification oil were the variables that had a significant effect (p < 0.05) on the biodiesel yield. The highest yield biodiesel (90%) was obtained with a catalyst concentration of 0.4%, at a temperature of 50 ° C, molar ratio methyl alcohol: oil of 3: 1 and time of 39 minutes of transesterification process. Its physical characteristics were: caloric power 9477 cal.g-1 , kinematic viscosity 7.53 mm 2 .s-1 , carbon residue 0.0817% and sulphated ash 0.005%. Thus, it was determined that it is feasible to obtain biodiesel using waste cherimoya.

The present work is focused on the revalorization of waste materials from the wine industry such as grape seed for the obtaining of grape oil using supercritical fluid technology. Malbec grape seed was used as raw material to obtain supercritical grape oil, as a potential value added product for both the pharmaceutical and food industries. An initial stage, the physicochemical characterization of the raw material was performed and the results obtained were: humidity (11.4%), proteins (8.1%), ashes (2.5%), fats (11.5%) and carbohydrates (66.5%). In the second stage, preliminary extraction tests with supercritical fluids were carried out using CO2 as a solvent. The following fixed operating parameters were established: average particle size (522.15 μm), supercritical extraction time in steady state (30 minutes), supercritical extraction time in dynamic state (180 minutes) and CO2 flowrate (5 ft3/h). The results were evaluated in terms of yield (g oil obtained / g raw material x100%). Subsequently, the parameters pressure (psi) an temperature (C) that significantly influenced (p <0.05) in the supercritical oil yield were evaluated using the Orthogonal Array L9 of the Taguchi methodology. The levels established for the pressures were: 2205,4410 and 6615 PSI, and the temperatures were: 40, 50 and 60ºC. The result indicated that both factors were significant and the best values respect to the performance of the supercritical oil were pressure (6615 PSI) and temperature (60ºC). In the next stage, we performed the optimization of the significant factors pressure and temperature by applying the Response Surface Methodology, with a central composite design (4 factorial treatments, 4 axial treatments and 2 central point treatments). The optimal temperature and pressure were 68 °C and 7655 psi with an extraction yield of 8.14 percent. Finally, the physico-chemical characterization of the obtained supercritical oil shows that linoleic and oleic fatty acids were found in highest proportion: 64.9 percent and 21.8 percent, respectively.