Showing papers by "Maurício de Oliveira published in 2019"
TL;DR: Increase in drying temperature reduced the total content of free-phenolics, free-flavonoids, and anthocyanins and a reduction of total phenolics occurred regardless of the storage condition, but storage under nitrogen-atmosphere is the most recommendable condition for maintenance of phenolics in black rice.
58 citations
TL;DR: In this article, the influence of the germination process for 48h on the nutritional components and bioactive compounds of chickpeas was evaluated and it was shown that germination promoted an increase in crude protein content and protein solubility, without altering protein digestibility.
Abstract: Germination is a widely used process to reduce antinutritional factors and enhance the nutritional value of several grains. The aim of this study was to evaluate the influence of the germination process for 48 h on the nutritional components and bioactive compounds of chickpeas. Proximal composition, protein solubility, lipid acidity, fatty acid profile, total phenolic compounds, antioxidant activity, total carotenoids, individual tocopherols and γ-aminobutyric acid (GABA) were evaluated. Germination promoted an increase in crude protein content and protein solubility, without altering protein digestibility (above 85.4%). It also reduced the content of carotenoids and tocopherols; however, the profile of unsaturated fatty acids remained unchanged. Increase in the phenolic compound levels, antioxidant activity and GABA content (6.42–245.76 mg/100 g) showed that germination makes chickpea an excellent source of bioactive compounds.
43 citations
25 citations
TL;DR: Results indicate that the release and interconversion of isoflavone malonyl-β-glucosides and β-glUCosides into aglycone forms are simultaneous reactions during storage.
Abstract: The changes in phenolic acid and isoflavone profile of soybean genotypes (Nidera 5909 RR and BMX Forca RR) dried at different temperatures and stored for 12 months were investigated. In both cultivars, there was a reduction of the germination capacity and an increase of fungal incidence with the increase of drying temperature and storage time. Multivariate analysis of phenolic acids allowed for the differentiation among treatments. Cultivar Nidera 5909 RR, dried at 110 °C, showed an interaction with characters of greater relevance for differentiation, being influenced by the increase of bound coumaric, and syringic, and free-hydroxybenzoic, syringic, and coumaric acids. Multivariate analysis of isoflavones showed a strong affinity of the aglycone isoflavones (genistein, glycitein, and daidzein) within the Nidera 5909 RR cultivar at all drying temperatures and with BMX Forca RR cultivar at the highest temperatures. These results indicate that the release and interconversion of isoflavone malonyl-β-glucosid...
19 citations
TL;DR: In this paper, the effects of microwave irradiation used for the rapid parboiling process on the morphological, technological, and structural properties of rice grains were evaluated and the microwave irradiated rice grains absorbed more water and lost less leached solids compared to those parboiled using the conventional method.
Abstract: This study evaluates the effects of microwave irradiation used for the rapid parboiling process on the morphological, technological, and structural properties of rice grains. Parboiling was performed by microwave under the same temperature and soaking and autoclaving conditions as those used in the conventional process. However, two heating stages were used at different microwave irradiation exposure times: (a) first stage (FS): 10, 20, 30 or 40 min; (b) second stage (SS): 0, 5, or 10 min. The rice grains submitted to the FS of microwave irradiation absorbed more water and lost less leached solids compared to those parboiled using the conventional method. Unlike conventional parboiling, microwave irradiation decreased the cooking time of the rice grains and modified their protein solubility. Furthermore, this technique modified the paste properties, morphology and crystalline structure of grains. These findings suggest a great impact on chemical and physic characteristics of parboiled rice by microwave irradiation. The microwave irradiation in the parboiling process significantly reduced the processing time (one-tenth as long than that required for the conventional process) and allowed obtaining of parboiled rice grains with greater whiteness and with faster cooking.
16 citations
TL;DR: Under favorable conditions, a reduction in the levels of broken and nongelatinized grains, residual phosphorus, and color changes was observed, indicating that microwave irradiation may be more beneficial than conventional parboiling.
Abstract: The conventional prolonged parboiling process results in high operation cost and grain darkening, which may limit consumption. Moreover, residue generation by rice industries is another challenge. The objective of this study was to evaluate the use of microwave irradiation during soaking and gelatinization stages of parboiling rice. Processing time, colorimetric profile, broken and nongelatinized grains, sucrose and glucose content, free 5-hydroxymethyl-2-furfural, and residual phosphorus were evaluated. As the soaking and gelatinization times during microwave treatments increased, the colorimetric parameters increased; however, the values were lower than those with the conventional process. Regardless of soaking time, a decrease in broken and nongelatinized grains was obtained by using the lowest steaming time (5 min). Additionally, lower residual phosphorus content was found in soaking water (10 and 20 min) when using microwave irradiation. Under favorable conditions, a reduction in the levels of broken and nongelatinized grains, residual phosphorus, and color changes was observed, indicating that microwave irradiation may be more beneficial than conventional parboiling. PRACTICAL APPLICATION: Parboiling requires a high volume of water and soaking time, which leads to high costs, underutilization of infrastructures, and high residue in the water after processing. The rapid parboiling process involves the use of microwaves during the soaking and gelatinization stages. The main advantages of the microwave parboiling process include reduced processing time, ranging from 83% to 95%, higher gelatinization, greater yield, reduced darkening, and reduced residual phosphorus in the effluents by 60%. This report can aid industries in streamlining their processes, thereby providing a high-quality, lower cost, and environmentally safe product.
2 citations