ABSTRACT
ABSTRACT This study aimed to evaluate the effect of Spirulina platensis and moderate exercise on oxidative stress and lipid profiles in the rats. Forty male Wistar rats were allocated to the following 10-week treatments, three times a week: exercise (E, 30 min swimming),S. platensis (SP, 26 mg/Kg); exercise andSpirulina (ES); and control (C). Outcomes were Thiobarbituric Acid Reactive Substances (TBARS) in serum and brain, and cholesterol and triglycerides (TG) in serum. Rats treated with exercise showed lower brain TBARS than the controls, mostly in association withS. platensis. In the groups E and ES, serum TBARS decreased after intervention. Compared with the controls, both E and ES prevented an increase in cholesterol and reduced triglycerides. Results demonstrated thatS. platensis enhanced the beneficial effect of exercise on oxidative stress and lipid profiles in rats, which might be a promising approach for treating metabolic syndrome in humans.
ABSTRACT
Na produção de pães integrais de trigo no Brasil, são utilizadas mesclas de farinha integral (FI) com farinha refinada (FR), as quais diferem em sua composição. Assim, o objetivo deste estudo foi investigar as propriedades de pasta de mesclas de FI com FR. Foram analisadas amostras com 100% de FI, 100% de FR (controles) e mesclas de FI com FR nas proporções de 20, 40, 60 e 80%, em equipamento RVA (Rapid Visco Analyzer). A temperatura de pasta das amostras foi semelhante. A viscosidade máxima diminuiu proporcionalmente com o aumento de FI na mescla. Maiores valores de quebra e de viscosidade mínima à temperatura constante foram encontrados em farinhas com pico de viscosidade elevado. Os valores de viscosidade final e de tendência à retrogradação diminuíram à medida que aumentou o teor de FI na mescla. As propriedades de pasta das mesclas de FI com FR devem ser vistas de forma conjunta, pois afetam a produção de pão e o armazenamento. Os resultados mostraram também que o RVA pode ser usado para ajudar a formular mesclas de FI/FR com certas propriedades de pasta.
In whole wheat bread production in Brazil blends of whole flour (WF) with refined flour (RF) are used, which differ in their composition. Thus, the objective of this study was to investigate the pasting properties of WF with RF blends. Samples with 100% of WF, 100% of RF (controls) and blends of WF with RF in the proportions of 20, 40, 60 and 80% were analyzed, in a RVA (Rapid Visco Analyzer) equipment. The samples pasting temperatures were similar. The peak viscosity decreased proportionally with the increase of WF in blends. Higher values of breakdown and holding strength were found in flour with high viscosity peak. Final viscosity and setback values decreased as the content of WF in blends increased. The pasting properties of WF with RF blends must be seen in a combined way, because they affect bread production and storage. The results also showed that RVA can be used to help in formulating WF/RF blends with certain pasting properties.
ABSTRACT
O objetivo do trabalho foi avaliar os parâmetros da extração de β-glucanas de cevada e caracterizar parcialmente o amido residual da extração. Foi desenvolvida metodologia para extração de β-glucanas de cevada sem degradação do amido, avaliando as variáveis pH e temperatura de extração. O percentual de β-glucanas extraída variou de 44,21 a 53,38 por cento, sendo influenciado pela temperatura, e o de amido extraído variou de 65,98 por cento a 77,54 por cento, sendo influenciado pelo pH. O amido residual da extração de β-glucanas de cevada apresentou poder de inchamento e solubilidade de 8,54±0,29 por cento e 6,04±0,073 por cento, respectivamente. O amilograma de ARV desse amido apresentou viscosidade máxima de 164,67±1,30 RVU e quebra de viscosidade de 45,79±2,06 RVU. O espectro de infravermelho do amido residual é típico de amido de cevada nativo e semelhante ao de amidos isolados de milho, trigo e mandioca. De acordo com as micrografias eletrônicas de varredura da fração amido, foi possível visualizar uma mistura de grânulos grandes e lenticulares, com um diâmetro médio de 19,15µm e de granulos pequenos com forma esférica, de 4,78µm. As características demonstradas pelo amido residual da extração de β-glucanas de cevada sugerem sua viabilidade para utilização na indústria de alimentos.
The objective of the study was to evaluate the parameters of the extraction of barley´s β-glucans and partially characterize the residual starch after extraction. A method was developed for the extraction of barley β-glucans without damaging the residual starch, assessing the variables pH and extraction temperature. The percentage of β-glucans in the extracted fraction varied from 44,21 to 53,38 percent , being influenced by temperature and the extracted starch varied from 65,98 percent a 77,54 percent, being influenced by pH. The residual starch from barley's β-glucan extraction had a swelling power and solubility of 8.54±0.29 percent and 6.04±0.07 percent, respectively. The RVA´s amylograph for this starch showed a maximum viscosity of 164.67±1.30 RVU and breakdown viscosity of 45.79±2.06 RVU. The infrared spectrum of the residual starch was typical of native barley starch and similar to isolated starch from corn, wheat and cassava. According to the scanning electron micrographs fraction of starch, it was possible to see a mixture of large lenticular granules with an average diameter of 19.15µm and small spherically shaped ones, with 4.78µm. The characteristics showed by the residual starch from barley´s β-glucan extraction, suggest a possible application in the food industry.