An ethanol-based process to simultaneously extract and fractionate carotenoids from Mauritia flexuosa L. Pulp

Abstract

-Mauritia vinifera (buriti) is a palm tree that grows wild in different areas of Brazil, particularly in the Amazonian region. The buriti oil is rich in carotenoids, especially in b-carotene. The growing interest in other natural sources of b-carotene has stimulated the industrial use of buriti as a raw material for pulp oil extraction. Most processes are based on the conventional technologies, involving drying and pressing the pulp for oil recovery and further separation of carotenoids in a liquid phase using organics solvents. In the present work, the ethanol-based process was evaluated for simultaneous carotenoids recovering and fractionating from buriti pulp. The raw material and ethanol, 1:4 ratio, were placed in an erlenmeyer flask and maintained at 30rpm for 1 hour in a temperature-controlled bath at 65°C. The mixture was filtered under vacuum and cooling at 10 o C to allow for the separation of the solvent in two phases. Carotenoids composition, determined by HPLC, has indicated a b-carotene concentration about 12 times greater in the lower phase than in the upper phase. The profile of the carotenoids in the denser phase is quite similar to that of raw buriti oil, and the concentration of total carotenoids is 40% higher than that of the original raw oil, making the ethanol-based process particularly attractive for industrial applications. Index Terms: Beta-carotene, vegetable oil, ethanol, buriti. USO DO ETANOL COMERCIAL PARA EXTRAÇÃO E FRACIONAMENTO SIMULTÂNEO DE CAROTENÓIDES DE MAURITIA FLEXUOSA L. PULPRESUMO-Mauritia vinifera (buriti) é uma palmeira nativa de diferentes regiões do Brasil, particularmente na região Amazônica. O óleo de buriti é rico em carotenoides, especialmente em b-caroteno. A demanda por fontes naturais de b-caroteno tem contribuído para aumentar a industrialização do fruto de buriti pelas usinas de extração de óleos vegetais. O processo mais adotado baseia-se em tecnologias convencionais envolvendo as etapas de despolpamento, secagem e prensagem da polpa para extração do óleo, seguida da separação dos carotenoides em uma fase líquida usando solventes orgânicos. Neste trabalho, foi avaliado o uso do etanol comercial para extração e fracionamento simultâneo de carotenoides a partir da polpa de buriti. A matéria-prima foi misturada com etanol, na proporção 1:4 solvente/substrato, e mantida em banho termostatizado a 60 o C, por 1 hora, sob agitação constante de 30 rpm. A mistura foi filtrada sob vácuo e resfriada a 10 o C, resultando na formação de duas fases. A composição de carotenoides foi determinada por CLAE e indicou uma concentração de b-caroteno 12 vezes maior na fase mais densa que na fase leve. O perfil de carotenoides foi similar ao obtido no óleo bruto de buriti, porém a concentração de carotenoides totais foi 40% maior, indicando que o processo tecnológico avaliado é particularmente promissor para aplicação industrial. Termos para Indexação: b-caroteno, óleo vegetal, etanol, buriti.Rev. Bras.

Refining of buriti oil (Mauritia flexuosa) originated from the brazilian cerrado: physicochemical, thermal-oxidative and nutritional implications

“…The acidity index may vary depending on the maturity of the vegetable from which the oil is extracted, 26 on thermal treatments 27 and on refining process. 25 According to Ribeiro et al, 28 the maximum free fatty acids content should be 5% for crude buriti oil and 1% for refined buriti oil, and it was observed that the oils analyzed in this study are within the standards recommended. During the refining process, the free fatty acids content must be reduced to an acceptable level recommended by current legislation, and this occurred after the refining process.…”

“…kg -1 for unrefined oils are acceptable, since at this stage, the rancidity taste is noticeable. 31 However, according to parameters reported by Ribeiro et al 28 and Shahidi, 32 the maximum peroxide index for crude oil must be 10 mequiv. kg -1 and for refined buriti oil 7 mequiv.…”

“…A higher absorption peak of about 459 nm could be observed in the refined buriti oil due to oxidative cleavage of carotenoids into apocarotenoids during the refining process, 28 which showed absorbance regions around 410 and 476 nm. 35 It was found that crude and refined buriti oil samples showed similar TG profiles, with three common steps of mass variation (Table 2 and Figure 2a).…”

“…According to Gunstone,36 during the refining process, unsaponifiables are partially removed or degraded during neutralization, bleaching and deodorizing stages. According to Ribeiro et al,28 in the degradation of carotenoids, β-carotene is transformed into apocarotenoids, especially 10-apo-β-carotenal, which explains the reduced vitamin A and carotenoid contents in crude buriti oil compared to refined buriti oil. However, the apocarotenoid formed could be used in the manufacturing of margarine as a substitute for synthetic dyes such as canthaxanthin and 8-apo-β-carotenal.…”

Optimization of oil extraction from high energetic potential plants performed through drying and solvent extraction methods

“…Saxena et al (2011) reported that the color of the oil extracted with ethanol solvent is a little bit darker than the color of oil extracted with hexane. Works that compare the extraction methods using biorenewable solvent and traditional fossil solvent (hexane) or pressing methods can be found in the literature by Brossard-González et al (2010), Ribeiro et al (2010), Ferreira-Dias et al (2003 and Drumond et al (2006). These authors emphasize that despite the better results of oil yield obtained by hexane extraction in some cases, its cost is high, and this can be a significant factor when compared to the low cost and the ease of use of ethanol; what adds to the much higher toxicity that hexane presents.…”