Desenvolvimento de extrato hidrossolúvel à base de castanha-do-brasil (bertholletia excelsa) e macadâmia (Macadamia integrifolia)

• Autor(a) principal: Machado, André Luiz Borges
• Data de Publicação: 2017
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/7066
• topic: Castanha-do-Brasil; Bertholletia excelsa; Macadâmia; Macadamia integrifolia; Simplex centroide; Vida útil; Reologia; Extrato Hidrossolúvel; Brazil nut; Bertholletia excelsa; Macadâmia; Macadamia integrifolia; Shelf life; Rheology; Water-soluble extract; ENGENHARIA QUIMICA::PROCESSOS INDUSTRIAIS DE ENGENHARIA QUIMICA

Brazil nut (Bertholletia excelsa) and Macadamia (Macadamia integrifolia) are rich feeds with excellent nutrients with higher quality. The main form of consumption of these nuts and almonds are in natura, but there are products which can be elaborated using these raw materials with high nutritional value and pleasant flavor. Water-soluble extracts are an alternative to consume them, which consist of fluid food of plant origin, that can be produced by nuts, oleaginous and even some grasses and they have great commercial appeal since they are free of animal’s fats, “lac free” (free of lactose) and have high rate of minerals. Thus, this research aimed to determine the best formulation, to accompany physical and microbiological stability, proximal composition, to estimate the shelf life and to determine the rheological behavior of a water-soluble extract made of Brazil nut and Macadamia. For the construction of mathematical models, with the purpose of knowing the effect of the variation of water, Brazil nut and Macadamia concentrations, basic components in the elaboration of the product on the proximal composition and physical aspects such as pH, titratable acidity and colorimetry, a simplex centroid design for mixtures was used and provided quadratic and cubic models showing excellent adjustment of experimental data. The Global Acceptance and Purchase Intention tests were performed for each experiment proposed by simplex centroid design and the Tukey test was used in order to determine the best proportion among the components of the ternary mixture. The formulation of water-soluble extract composed of 70% (w/w) water, 15% (w / w) Brazilian nut and 15% (w/w) Macadamia was considered to be the most preferred by tasters submitted to the sensory evaluations. In order to improve the product’s flavor, 10% (w/v) of sugar, expressed as sucrose, was added and the concentration of preservatives citric acid, potassium sorbate and sodium benzoate was reduced. The product was processed technologically under hygienic conditions and filled in 220 ml transparent glass bottles, hermetically sealed with metal crown cork, pasteurized at 80 °C/25 min, stored under refrigeration at 4 ° C and had its stability evaluated during 28 days. Growth of Thermotolerant Coliforms, Positive Coagulase Staphylococci, Salmonella sp, Molds and Yeasts during the evaluation period was not detected. There was a significant variation (p < 0.05) in pH in the first two weeks of storage, and remained without significant variation (p > 0.05) for the other weeks analyzed. The acidity remained constant throughout the lifetime. The product showed a yellowish-white color throughout the study, determined by the coordinates of the colorimetry. Sensory analysis scores for odor, color, taste and global impression averaged around 6, thus, concluding that the product has a 28 days of shelf life. The rheological profile of the beverage was evaluated at three different temperatures, at 25 °C (room temperature), at 45 °C (temperature of the disintegration stage of Brazil nut and Macadamia with water in blender), and at 80 °C, (pasteurization temperature). The Ostwald-de-Waele model was considered the best to describe the beverage flow and since the calculated flow rate of the model, was less than 1 at the temperatures studied, it had concluded that the beverage behaved as a fluid Non-Newtonian pseudoplastic. The apparent viscosity curves of the mixed drink were plotted and showed that the apparent viscosity decreased significantly (p < 0.05) with the increasing of temperature.