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Modifica??o por via enzimática da composi??o triglicerídica do óleo de piqui (Caryocar brasiliense Camb)
Facioli, Nara Lúcia;Gon?alves, Lireny A.G.;
Química Nova , 1998, DOI: 10.1590/S0100-40421998000100003
Abstract: piqui (caryocar brasiliense camb) oil was transformed into a cocoa butter-like fat through an enzymatic interesterification reaction using lipozyme in the presence of stearic acid that was incorporated in the sn 1,3-3,1 position into triglyceride. stearic acid incorporation was determined by hplc, based on the quantification of the principal triglycerides (pop, pos e sos) found in cocoa butter. the proposed process was feasible with a reaction time of 240 minutes with 10% of lipozyme at 70oc and substract weight ratio of 0,33 (stearic acid:piqui oil).
Optimización del proceso de esterificación química del destilado de desodorización del aceite de soja previamente saponificado y acidulado
Facioli, Nara Lúcia,Barrera-Arellano, Daniel
Grasas y Aceites , 2002,
Abstract: In this research work, it was optimized the reaction conditions for the chemistry esterification of unsaponifiable matter in soybean oil deodorizer distillate. The process involves (i) alkaline hydrolysis of saponifiable matter; (ii) acidulation of soaps and (iii) acid catalyzed esterification of resulting total fatty acid. To determine the best process conditions to get the higher conversion rates of total fatty acids to ethylic esters, preserving the tocopherols, it was used, to analyze the results, the response surface methodology in a 2nd order factorial planning. In the step (i) saponification of soybean oil deodorizer distillate saponifiable matter using NaOH:total fatty acids molar ratio = 2:1, temperature = 80 o C and reaction time of 40 min. In the step (ii) the resulting soaps were rapidly and stoichiometrically converted in free fatty acids with sulfuric acid (23 %), using an acid molar excess of 50 %, at 80 o C, for 40 min and under atmospheric pressure. In the step (iii) the optima conditions for the esterification reaction of soybean oil deodorizer distillate were: ethanol:total fatty acids molar ratio from 6.4 to 11.2:1, SO2H4 concentration from 0.9 to 1.5 % and reaction time from 1.3 to 2.6 h, with ethyl esters conversion rates up to 98 %. The mathematical model obtained is predictive and statistically significant (p<0,05). The total tocopherol losses during the process were less than 10,5 %. En esta investigación fueron optimizadas las condiciones de reacción de esterificación de la materia saponificable del destilado de desodorización del aceite de soja. El proceso engloba (i) hidrólisis alcalina da materia saponificable; (ii) acidulación de los jabones y (iii) esterificación catalizada por ácido de los ácidos grasos totales resultantes. Las condiciones óptimas del proceso, para obtener el mayor rendimiento en ésteres etílicos y perdidas mínimas de tocoferoles, fueron determinadas usando la metodología de superficie de respuesta de un dise o factorial completo de 2a orden. Etapa (i) saponificación de la materia saponificable del destilado de desodorización del aceite de soja, usando: relación molar etanol:ácidos grasos totales = 2:1, temperatura = 80 o C y tiempo de reacción = 40 minutos. Etapa (ii) los jabones formados fueron rápidamente convertidos en ácidos grasos libres utilizando ácido sulfúrico (23 %), con exceso molar del 50 %, a 80 o C, durante 40 minutos a presión atmosférica. Etapa (iii) las condiciones óptimas para la reacción de esterificación del destilado de desodorización del aceite de soja saponificado y acidificado fue
Optimization of direct acid esterification process of soybean oil deodorizer distillate
Facioli, Nara Lúcia,Barrera-Arellano, Daniel
Grasas y Aceites , 2002,
Abstract: In this research work, the reaction conditions for the direct acid esterification of free fatty acid from soybean oil deodorizer distillate was optimized, using anhydrous ethyl alcohol and concentrated sulfuric acid as catalyst to determine the best process conditions to get the best conversion rates of free fatty acids to ethylic esters, preserving the tocopherols. The conversion extent of free fatty acids to ethyl esters was optimized using a Response Surface Methodology obtained through a second order factorial experimental design. The optima conditions for the direct acid esterification of soybean oil deodorizer distillate were: ethanol:free fatty acids from 6.4 to 11.2:1, H2SO4 concentration from 0.9 to 1.5 % and reaction time from 1.3 to 2.6 h, with conversions extent above 94 %. No significant tocopherol losses were observed during the process. Results showed a good fit between mathematical model and data obtained at different processing conditions, making this model predictive and statistically significant (p< 0,05). En este estudio fueron optimizadas las condiciones de reacción de esterificación ácida directa de los ácidos grasos libres del destilado de desodorización del aceite de soja, usando alcohol etílico anhidro y ácido sulfúrico concentrado como catalizador. Fueron determinadas las mejores condiciones de proceso para obtener las tasas de conversión más altas de ácidos grasos libres en ésteres etílicos, manteniendo los tocoferoles. Los resultados fueron analizados mediante la metodología de superficie de respuesta usando un delineamiento experimental factorial completo de segundo orden. Las condiciones óptimas encontradas para la esterificación ácida directa del destilado de desodorización del aceite de soja obtenidas fueron: etanol:ácidos grasos libres entre 6.4 y 11.2:1, concentración de ácido sulfúrico entre 0.9 y 1.5 % y tiempo de reacción entre 1.3 y 2.6 h, obteniendo tasas de conversión mayores que 94 %. No fueron observadas pérdidas significativas de tocoferoles durante el proceso. Los resultados mostraron un buen ajuste entre el modelo matemático y las respuestas experimentales para las diferentes condiciones del proceso, lo que permite considerar el modelo como predictivo y estadísticamente significativo (p< 0.05).
Modifica o por via enzimática da composi o triglicerídica do óleo de piqui (Caryocar brasiliense Camb)
Facioli Nara Lúcia,Gon?alves Lireny A.G.
Química Nova , 1998,
Abstract: Piqui (Caryocar brasiliense Camb) oil was transformed into a cocoa butter-like fat through an enzymatic interesterification reaction using Lipozyme in the presence of stearic acid that was incorporated in the sn 1,3-3,1 position into triglyceride. Stearic acid incorporation was determined by HPLC, based on the quantification of the principal triglycerides (POP, POS e SOS) found in cocoa butter. The proposed process was feasible with a reaction time of 240 minutes with 10% of Lipozyme at 70oC and substract weight ratio of 0,33 (stearic acid:piqui oil).
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