Suely Pereira Freitas

Composição em ácidos graxos do óleo da polpa de açaí extraído com enzimas e com hexano

Acai (Euterpe oleracea Martius) is a typical palm tree from the Amazon, growing spontaneously in states of Para, Amazonas, Amapa and Maranhao. It has been highlighted by the potential of its products, especially because of the economic importance for the regional fruit growing. The acai fruits are very appreciated by their pulp flavour. In the acai pulp, there is a significant amount of lipids, around 53%, in a dry basis, turning out to be an excellent source of essential fatty acids. The main purpose of the present work was to establish the fatty acid content in the lipid fraction of acai pulp using high resolution gaseous chromatography. The acai oil was obtained by enzymatic technology in water has been indicated as an alternative for vegetable oils extraction from pulp of fruits. A significant difference was not observed in the composition of the fatty acids present in acai oil obtained from either process. In both cases, the oil is high in monounsaturated fatty acids (68% to 71%) and in polyunsaturated fatty acids (7.8% to 10.6%).

Enzymatic technology to improve oil extraction from Caryocar brasiliense camb. (Pequi) Pulp.

O presente estudo tem como objetivo comparar o rendimento e a qualidade do oleo da polpa de pequi obtido por dois processos distintos: no primeiro, a secagem da polpa, conduzida em secador de bandeja a 60oC, foi combinada com tratamento enzimatico e prensagem para extracao de oleo, no segundo, um processo mai simples foi realizado combinando-se a secagem da polpa ao sol seguida da prensagem a frio. Neste estudo, frutos de pequi in natura foram coletados no estado do Mato Grosso, Brasil. Os frutos foram auto-clavados a 121o C e armazenados sob refrigeracao. Um extrato enzimatico com atividades pectinase e CMCase foi utilizado para a hidrolise da polpa de pequi antes da extracao do oleo. O processo de extracao foi realizado por prensagem hidraulica, com ou sem incubacao enzimatica. O teor de oleo na polpa do pequi (45% w/w) e as caracteristicas fisico-quimicas do oleo foram determinados de acordo com metodos analiticos oficiais. O teor de acidos graxos livres, os indices de peroxido, de iodo e de saponificacao foram respectivamente de 1,46 mgKOH/g, 2,98 meq/kg, 49,13 e 189,40. A acidez e os valores de peroxido foram inferiores aos valores obtidos em amostras comerciais de oleo vegetal, respectivamente, 2,48 mgKOH/g, 5,22 meq/kg. A extracao aquosa apresentou menor eficiencia e promoveu uma maior oxidacao dos acidos graxos insaturados. Por outro lado, a polpa de pequi prensada, apos secagem ao sol, produziu um oleo de melhor qualidade. No entanto, sua eficiencia ainda e menor do que no processo combinado onde se aplicou o tratamento aquoso enzimatico seguido da prensagem. O processo combinado promove a hidrolise da parede celular e a reducao da viscosidade da polpa, contribuindo com pelo menos 20% de aumento na produtividade da etapa de extracao do oleo por prensagem.

Antioxidant dietary fibre recovery from Brazilian Pinot noir grape pomace

Brazilian grape pomace was extracted in hot water, and a factorial experiment was used to evaluate polysaccharide recovery. The dependent variables were the temperature, particle size and solute:solvent ratio. Polysaccharide yields varied from 3% to 10%, and the highest sugar content was observed when extraction was carried out at 100 °C from finely sized particles (⩽249 μm) in a 1:12 solute:solvent ratio. The monosaccharide composition of extracts obtained from flours were, on average, Rha:Ara:Xyl:Man:Gal:Glc:GalA in a 3:32:2:13:11:20:19 M ratio, with varying Glc:GalA ratios. (13)C NMR and HSQC spectra confirmed the presence of pectic- and glucose-based polysaccharides in the extracts. Phenolic compounds were found after pomace extraction, and catechin, gallic acid and epicatechin were the principal compounds identified. The extracts also had ABTS radical scavenging capacity (from 8.00 to 46.60 mMol Trolox/100 g pomace). These findings indicate that these grape pomace flours are rich in antioxidant dietary fibre and have a potential use as food ingredients.

Extração e fracionamento simultâneo do óleo da castanha-do-Brasil com etanol

O objetivo deste trabalho foi utilizar o etanol comercial para extracao e fracionamento simultâneos das fracoes lipidicas presentes na castanha-do-Brasil (Bertholletia excelsea H.B.K.). O oleo foi obtido a partir da castanha desidratada e moida. O processo foi conduzido na proporcao 4:1 solvente/substrato (v.p-1) em banho termostatizado a 65 °C, sob agitacao de 30 rpm. A mistura foi filtrada, resfriada a 10 °C e, a seguir, centrifugada para separacao das fases: uma fase com consistencia de gel (micela rica), contendo 75% de oleo e 25% de etanol, e a outra liquida, contendo 2,4% de oleo e 97,6% de etanol (micela pobre). Pelas caracteristicas apresentadas, a micela rica tem potencial para ser utilizada no preparo de cremes vegetais como substituto parcial de gorduras hidrogenadas, cujos efeitos biologicos na saude dos consumidores vem provocando muitas polemicas. Alem de ser uma alternativa na obtencao de gorduras para a formulacao de alimentos mais seguros, a tecnologia proposta podera ser estendida a diferentes oleaginosas de interesse comercial, eliminando o uso de n-hexano no processamento de oleos e gorduras vegetais.

Towards integral utilization of grape pomace from winemaking process: A review

Grape is the main fruit crop in several countries. Although many grape-based food products can be found in the market, studies have shown that around 75% of the world grape production is destined for the wine industry. Grape pomace is an abundant by-product from the wine industry, which consists of the remaining skin, seeds and stalks and represents around 25% of total grape weight used in the winemaking process. In countries such as Italy, France and Spain, where wine production is more relevant, the annual grape pomace generation can reach nearly 1200 tonnes per year. In order to reach a sustainable winemaking process there is a need of a waste reduction policy. Several studies explore this subject using grape pomace as a source of healthy and technological compounds that could be applied in animal feed, pharmaceutical, cosmetic or food industry to improve stability and nutritional characteristics, and in cosmetic industry, where grape seeds oil is widely used. This review aims to approach the recent winemaking scenario and the benefits achieved when a waste management policy is implemented, as well as to compare available extractive technologies and a wide alternative of uses for grape pomace.

Partition of Free Fatty Acids in Deacidification of Macaúba Pulp Oil by Liquid-Liquid Extraction Using Ethanol/Water as Solvent

Free fatty acids (FFA) is one of the most frequently determined quality indices in fats and oils industry because it has the economic impacts on production [1]. The FFA in macaúba pulp oil is usually very high (10 to 40%) due to enzymatic activity in the raw material [2]. In this case, alkali neutralization is not economically recommended due to neutral oil loss by occlusion in soapstock. The differential solubility of fatty acids and triacylglycerides (TAG) in various organic solvents has formed the basis of several processes for deacidification of crude oils by liquid–liquid extraction [3]. The aim of the present work was to evaluate the influence of raw oil acidity, ethanol/water ratio, water content in ethanol and temperature extraction on partition coefficients of FFA during macaúba oil deacidification. The macaúba crude oil presented high acid index, about 86  1.2 mg KOH/g. The extraction data for the system macaúba oil + free fatty acids + ethanol + water was determined for oil:solvent mass ratios 1:1. Alcoholic solutions containing 2 to 10 % (w/w) of water were used to FFA extraction and the partition coefficients were determined after 24 hours at room temperature (293 K). The phase’s separation was observed for water content in the mixture above 4%. After solvent evaporation, the FFA in oil phase was evaluated by AOCS standard method. Regarding the high acid oil, the single stage liquid-liquid extraction reduced the FFA in macaúba pulp oil in about 23 % while the three batch stages reduced up to 60%. At the selected parameters (ethanol 94oGL, solvent/substrate ratio = 2), the partition coefficients in the firs stage to FFA (KFFA) were 30.45, 12.00 and 1.95, respectively to high acid, acid and low acid macaúba oils and the partition coefficients to TAG (KTAG) were 7.07, 0.04 and 0.02, respectively to high acid, acid and low acid macaúba oils. These results show the potential of ethanol to vegetable oil deacidification. Besides reduced generation of environmental pollutants, this new approach could also lead to reduction in oil losses, especially for low acid oil.

Oxidative stability and sensory evaluation of microencapsulated flaxseed oil

Abstract Cold pressed flaxseed oil was microencapsulated by spray drying using an emulsion containing modified starch. The fatty acid composition, moisture, water activity, wettability, water holding capacity, water solubility, crystallinity, and particle size distribution of the microcapsules were determined. The stability of the microcapsules and the crude oil were assessed. An acceptance test was used for the sensory evaluation of a powdered supplement containing the microcapsules. The fatty acid composition was not significantly affected by the microencapsulation. The moisture, water activity, wettability, water solubility and crystallinity were appropriate for dry powders. The microcapsules had no cracks and showed better oxidative stability compared with the crude oil. Storage under vacuum prevented oxidation of the microcapsules. In sensory evaluation, all quality scores of the supplement containing microcapsules were mid-range or higher. The microencapsulation improved the oxidative stability of the oil and this procedure was satisfactorily applied in powdered food.

Discriminação entre estádios de maturação e tipos de processamento de pós-colheita de cafés arábica por microextração em fase sólida e análise de componentes principais

A fruit chemical composition reflects its maturation stage. For coffee, it is also the reflex of the post-harvesting processing type, dry, semi-wet and wet. The object of this work was to verify if headspace solid phase microextraction coupled to gas chromatography (HS-SPME-GC) could be used to discriminate between samples harvested in different maturation stages and treated by different processes. With application of principal component analysis to the area of 117 compounds extracted by SPME, using divinylbenzene/Carboxen/polydimethylsiloxane fiber, it was possible to discriminate, in the roasted and ground coffee, the maturity stage and processing type used .

Correlação entre precursores e voláteis em café arábica brasileiro processado pelas vias seca, semiúmida e úmida e discriminação através da análise por componentes principais

The influence of pre-processing of arabica coffee beans on the composition of volatile precursors including sugars, chlorogenic acids, phenolics, proteins, aminoacids, trigonelline and fatty acids was assessed and correlated with volatiles formed during roasting. Reducing sugars and free aminoacids were highest for natural coffees whereas total sugars, chlorogenic acids and trigonelline were highest for washed coffees. The highest correlation was observed for total phenolics and volatile phenolics (R= 0.999). Experimental data were evaluated by Principal Components Analysis and results showed that washed coffees formed a distinct group in relation to semi-washed and natural coffees.

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

Mauritia vinifera (buriti) e uma palmeira nativa de diferentes regioes do Brasil, particularmente na regiao Amazonica. O oleo de buriti e rico em carotenoides, especialmente em β-caroteno. A demanda por fontes naturais de β-caroteno tem contribuido para aumentar a industrializacao do fruto de buriti pelas usinas de extracao de oleos vegetais. O processo mais adotado baseia-se em tecnologias convencionais envolvendo as etapas de despolpamento, secagem e prensagem da polpa para extracao do oleo, seguida da separacao dos carotenoides em uma fase liquida usando solventes orgânicos. Neste trabalho, foi avaliado o uso do etanol comercial para extracao e fracionamento simultâneo de carotenoides a partir da polpa de buriti. A materia-prima foi misturada com etanol, na proporcao 1:4 solvente/substrato, e mantida em banho termostatizado a 60oC, por 1 hora, sob agitacao constante de 30 rpm. A mistura foi filtrada sob vacuo e resfriada a 10oC resultando na formacao de duas fases. A composicao de carotenoides foi determinada por CLAE e indicou uma concentracao de β-caroteno 12 vezes maior na fase mais densa que na fase leve. O perfil de carotenoides foi similar ao obtido no oleo bruto de buriti, porem a concentracao de carotenoides totais foi 40% maior, indicando que o processo tecnologico avaliado e particularmente promissor para aplicacao industrial.