Navegando por Autor "RODRIGUES, Antonio Manoel da Cruz"

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Acesso aberto (Open Access)
Avaliação da influência da temperatura e do tratamento enzimático no comportamento reológico do suco de abacaxi pérola (Ananas Comosus L. merr.)
(2013-03) BRAGA, Adriano Cesar Calandrini; RODRIGUES, Antonio Manoel da Cruz; SILVA, Luiza Helena Meller da; ARAÚJO, Lícia Amazonas de
The objective this study was determinate the rheological behavior of pineapple juice natural and treated with pectinolytic enzymes. Tests for optimization of enzyme activity used in treatment were realized using a complete factorial planning 2k, with three repetitions of center point and two independent variables (temperature and time of treatment). In evaluation of rheological behavior of pineapple juice, were utilized two samples submitted to sieving (N and D), analyzed in four different temperatures (10, 25, 50 e 65 °C). The rheological analyses were realized using a Brookfield concentric cylinders viscometer and the relationship in the temperature and apparent viscosity was described by an equation type Arrhenius. The experimental data were adjusted by the Mizrahi-Berk model. The optimization tests indicated by ANOVA and response surface methodology that the variables temperature and time of treatment have statistically significant effect (p<0,05) on concentration of pectin present in the samples. The enzymatic treatment was carried with an enzyme concentration of 150 mg.L-1, temperature at 50 °C and treatment time of 80 minutes. The model used was adequate to describe the rheological behavior of the juices according to the parameters R2, χ2 e Bf. The reduced values of the behavior index (0.61-0.83 for natural juice and 0.57-0.72 for despectinized juice) indicated the pseudoplastic behavior (n<1). The temperature influenced the yield stress and apparent viscosity of the juices analyzed, where the minors values were observed in samples treated at 65 °C, 2.4 mPa.s and 1.4 mPa.s, respectively, for the natural and despectinized samples. The equation of Arrhenius described satisfactorily the effect of temperature in the apparent viscosity. The activation energy values (Eat) was of 4.54 Kcal.g.mol-1and 4.89 Kcal.g.mol-1, respectively, for the natural and despectinized samples of pineapple juice, increasing with enzymatic treatment. The enzymatic treatment decreased the values of rheological behavior parameters for samples of pineapple juice, and the apparent viscosity for all temperatures used, where the largest percentage reduction was observed at 65 °C (41.66%).
Acesso aberto (Open Access)
Comportamento reológico de suco misto elaborado com frutas tropicais
(2013-06) BEZERRA, Carolina Vieira; SILVA, Luiza Helena Meller da; COSTA, Rebeca Desireé Sousa da; MATTIETTO, Rafaella de Andrade; RODRIGUES, Antonio Manoel da Cruz
The rheological properties of a juice blend obtained from a tropical fruit mix were determined in this work using a rotational viscosimeter at temperatures from 10 ºC to 60 ºC. The Power law and Mizrahi-Berk models were fitted to the experimental data. All the models were considered adequate to describe the rheological properties of the juice blend according to the fitted statistical parameters. The behaviour index of the product was below 1.0, indicating the pseudoplasticity of the juice. The behaviour indexes for consistency were found to decrease with increase in temperature. The effect of temperature on the rheological behaviour of the juice was described by an Arrhenius type equation and discussed in terms of the activation energy (Ea). The values for Ea varied from 4.27 to 4.66 kcal.gmol-1 with increases in shear rate.
Acesso aberto (Open Access)
Fatty acid profiles and tocopherol contents of buriti (Mauritia flexuosa), patawa (Oenocarpus bataua), tucuma (Astrocaryum vulgare), mari (Poraqueiba paraensis) and inaja (Maximiliana maripa) fruits
(2010) RODRIGUES, Antonio Manoel da Cruz; DARNET, Sylvain Henri; SILVA, Luiza Helena Meller da
Amazonian fruits are rich in fat but have a fatty acid profile that may be beneficial in relation to risk of coronary heart disease. Amazonian fruits also contain other potentially cardioprotective constituents including tocopherols. Tocopherol profiles were determined by high performance liquid chromatography (HPLC), and fatty acid profiles were determined by gas chromatography (GC). In the present study, the total oil content, fatty acid composition and tocopherol content of the pulps of five Amazonian fruits (buriti, patawa, tucuma, mari and inaja) were measured. The total oil content of the fruits ranged from 31.0 to 41.8%. The major fatty acid in all of the fruits was oleic acid (C18:1), though substantial levels of palmitic acid (C16:0) were present. Linoleic acid (C18:2) was the main polyunsatured fatty acid observed. α-Tocopherol was the most prevalent tocopherol except in buriti pulp. Buriti and mari pulp have a high content in α-tocopherols with 297 and 155 µg g-1 of dry matter. Our data indicate that all five of these Amazonian fruits are good sources of unsaturated fatty acids and tocopherols.
Acesso aberto (Open Access)
Hygroscopic behavior of buriti (Mauritia flexuosa) fruit
(2011-12) MELO, Wellington dos Santos; PENA, Rosinelson da Silva; RODRIGUES, Antonio Manoel da Cruz; SILVA, Luiza Helena Meller da
The objective of this study was to perform an analysis of the characterization of buriti fruit (Mauritia flexuosa). Each part of the fruit (peel, pulp, and fibrous part) was analyzed and their hygroscopic behavior was evaluated to establish the drying and storage conditions. Adsorption and desorption isotherms were obtained at 25 °C to the monolayer value was estimated, and the application of the Halsey, Handerson, Kuhn, Mizrahi, Oswin, Smith, BET, and GAB models was evaluated to the prediction of the isotherms. The fruit pulp was classified as rich in high quality oil, and like the peel and the fibrous part, it was also considered as rich in dietary fiber. The isotherms of the fruit parts were classified as type II, and their microbiological stability (aw< 0.6) can be maintained at 25 °C if the moisture content is lower than 8.5, 7.3, and 11.0 g H2O.100 g-1 of dry matter (d.m.), respectively. The hygroscopic behavior showed that in order to ensure stability, the fruit parts should be packaged with low water vapor permeability. The monolayer demonstrated that the peel, pulp, and the fibrous part cannot be dried under moisture content lower than 5.9, 5.0, and 6.4 g H2O.100 g-1 d.m., respectively. GAB was the most adequate model to describe their isotherms.
Acesso aberto (Open Access)
Influence of temperature, concentration and shear rate on the rheological behavior of malay apple (Syzygium malaccense) juice
(Universidade Federal do Pará, 2016-06) SANTOS, Pedro Henrique; SILVA, Luiza Helena Meller da; RODRIGUES, Antonio Manoel da Cruz; SOUZA, José Antonio Ribeiro de
The aim of this study was to evaluate the rheological behavior of malay apple, a traditional Amazonian fruit with high bioactive properties, at different temperatures and soluble solids concentrations. The experiments were carried out in a Brookfield R/S Plus rheometer with concentric cylinders geometry. Power Law, Herschel-Bulkley, Mizrahi-Berk, and Sisko rheological models were fitted to the experimental data. The malay apple juice (pulp and skin) showed a pseudoplastic behavior for all temperatures and concentrations with flow behavior indexes lower than 1. The temperature effect on the samples’ apparent viscosity was analyzed by the Arrhenius equation. The activation energy increased with a decrease in the soluble solids concentration, showing that the lower the concentration, the greater the temperature influence on the apparent viscosity. The soluble solids effect was described by the exponential equation. The exponential factor increased with the temperature increasing, showing that the higher the temperature, the greater the effect of the soluble solids concentration on samples’ apparent viscosity. Finally, a triparametric mathematical model combining temperature, concentration, and shear rate was proposed aiming to evaluate its effects on the samples’ apparent viscosity and has accurately adjusted to the data with high correlation index R2.
Acesso aberto (Open Access)
Nutritional composition, fatty acid and tocopherol contents of buriti (Mauritia flexuosa) and patawa (Oenocarpus bataua) fruit pulp from the amazon region
(2011-06) DARNET, Sylvain Henri; SILVA, Luiza Helena Meller da; RODRIGUES, Antonio Manoel da Cruz; LINS, Roseana Telles
Buriti and patawa are two endemic palm trees from the Amazon region. Their pulps are traditionally consumed by the local population, but are underused and lesser known worldwide. Nutritional composition, fatty acid and tocopherol contents of the two palm pulps were determined by modern analytical methods: Gas Chromatography (CG) and High Performance Liquid Chromatography (HPLC), based on the standards of AOCS (AMERICAN..., 2002) and AOAC (ASSOCIATION..., 1997), respectively. Buriti and patawa fruit pulps are highly nutritive, with respectively, high fat content (38.4% and 29.1% of dry matter (DM)), protein content (7.6% and 7.4% of DM) and dietary fibers (46% and 44.7% of DM). Buriti pulp can be considered healthy food due its high content of vitamin E (1169 µg.g-1 DM). Patawa pulp is highly oleaginous and its fatty acid composition is very similar to the ones of healthy oils, such as olive oil.
Acesso aberto (Open Access)
Nutritional potential of green banana flour obtained by drying in spouted be
(Sociedade Brasileira de Fruticultura, 2013-12) BEZERRA, Carolina Vieira; RODRIGUES, Antonio Manoel da Cruz; AMANTE, Edna Regina; SILVA, Luiza Helena Meller da
This study evaluated the chemical composition of peeled and unpeeled green banana Cavendish (AAA) flour obtained by drying in spouted bed, aiming at adding nutritional value to food products. The bananas were sliced and crushed to obtain a paste and fed to the spouted bed dryer (12 cm height and T = 80 ºC) in order to obtain flour. The flours obtained were subjected to analysis of moisture, protein, ash, carbohydrates, total starch, resistant starch, fiber. The green banana flours, mainly unpeeled, are good sources of fiber and resistant starch with an average of 21.91g/100g and 68.02g/100g respectively. The protein content was found in an average of 4.76g/100g, being classified as a low biological value protein with lysine as the first limiting amino acid. The results showed that unpeeled green banana flour obtained by spouted bed drying can be a valuable tool to add nutritional value to products in order to increase their non-digestible fraction.
Acesso aberto (Open Access)
Propriedades reológicas do suco de buriti (Mauritia flexuosa)
(Universidade Federal do Pará, 2016-02) RODRIGUES, Antonio Manoel da Cruz; BEZERRA, Carolina Vieira; SILVA, Ivonete Quaresma da; SILVA, Luiza Helena Meller da
Knowing the rheological behavior of tropical fruit juices is very important for both consumers and food industry. This study investigated the rheological behavior of buriti (Mauritia flexuosa) juice. The rheological data were obtained through a rotational viscometer with concentric cylinder geometry (Brookfield, model DV II+). The assays were carried out at six different temperatures (10, 20, 30, 40, 50, and 60 °C) and the experimental results were adjusted through the Power Law and Mizrahi-Berk models. The buriti juice showed non-Newtonian behavior at the six temperatures. When quantifying apparent viscosity (hap), therheological parameters (K and n) were obtained by adjusting the Power Law, which was shown to be quite appropriate in predicting the juice’s rheological behavior, with determination coefficients r² > 0.99 for five out of the six temperatures investigated. The product showed pseudoplastic (n < 1) behavior and the flow behavior index decreased as temperature increased. The effect of temperature on apparent viscosity was described through an Arrhenius equation and discussed in terms of energy of activation (Ea) and the values of Ea ranged from 2.84 to 3.0 kcal/gmol for the strain rate used.
Acesso aberto (Open Access)
Rheological behavior of concentrated tucupi
(Universidade Federal do Pará, 2018-11) COSTA, Telma dos Santos; RODRIGUES, Antonio Manoel da Cruz; PENA, Rosinelson da Silva
Tucupi, which is widely enjoyed in the North region of Brazil, is a fermented liquid derived from cassava (Manihot esculenta Crantz) and has been taken abroad for its exotic characteristics. This study aimed to assess the rheological behavior of tucupi with 30, 35, and 40% solids and concentrated at 50, 70, and 90 °C. The rheological data were obtained at 25, 40, 60, and 80 °C with increasing and decreasing shear rates. Rheology at 25 °C indicated that the partial gelification of starch during concentration causes a decrease in the product’s viscosity and, if the concentration is carried out at a temperature that favors total starch gelification, the product’s viscosity increases. Concentrated tucupi behaved as a pseudoplastic fluid, but at 60 and 80 °C with increasing shear rates, the product behaved as a dilatant fluid. Hysteresis were observed in flow curves starting at 40 °C, which characterizes concentrated tucupi as a rheopectic fluid. The Ostwald-de Waele model predicted the product’s flow curves and an Arrhenius-like equation described the dependence of temperature on apparent viscosity for the rheological data obtained with increasing shear rates. The product’s activation energy (E a) values ranged from 16.86 to 25.23 kJ/mol as a function of concentration.