Soybean is a rich source of bioactive compounds, such as phenolic acids, flavonoids, isoflavones,... more Soybean is a rich source of bioactive compounds, such as phenolic acids, flavonoids, isoflavones, carotenoids, and tocopherols. The amount of bioactive compounds in freshly harvested soybeans and their derived products has been determined; however, when they are used in the food industry, soybeans are generally stored prior to being processed. This study aimed to evaluate the effects of soybean moisture content (12%, 15%, and 18%) and storage temperature (11, 18, 25, and 32 °C) on the free phenolic, total flavonoid, vanillic acid, total carotenoid, and δ- and γ-tocopherol content of soybeans stored for 12 mo. Moreover, the ABTS and DPPH radical scavenging activities of phenolic extracts were determined. There was an increase in free phenolics and total flavonoids in the stored grains compared with the grains on the 1st d of storage. Vanillic acid showed a decrease in soybeans stored at 15% and 18% moisture content and 25 or 32 °C, which indicated some degradation into other metabolites. Total carotenoid content decreased as a function of storage temperature and showed some temperature-dependent degradation. The δ- and γ-tocopherol content also tended to decrease in grains stored at 15% or 18% moisture content or 25 or 32 °C, regardless of the moisture content studied.
ABSTRACT The aim of this study was to evaluate the effects of utilizing an eolic exhauster on red... more ABSTRACT The aim of this study was to evaluate the effects of utilizing an eolic exhauster on reducing the qualitative losses of rice stored in silos. Paddy rice was stored for a nine-month period, in triplicate, in metal silos with a 550-ton capacity that were or were not equipped with an exhauster system and were analyzed every three months. To evaluate the effects of complementary eolic aeration, the energy consumed for aeration and the physical properties of the grain, as well as the thermal and pasting properties of rice, were analyzed. Using the exhauster system in the rice storage silo reduced the loss of dry matter, the energy required for aeration maintenance over a 9-month period, grain hardening, the development of grain staining defects and the darkening of the grain, while preserving the conclusion temperature of gelatinization and the enthalpy, the final viscosity and the head rice yield and not affecting the onset temperature or the peak temperature of gelatinization. Increasing the duration of storage reduced the aeration maintenance requirement, changed the cooking time, the hardness of the grains, the conclusion temperature and the enthalpy, the peak viscosity and final viscosity, the head rice yield, the development of grain staining and the darkening of rice grains, but with less intensity when the rice was stored in silos that used an exhauster system, without affecting the onset and peak temperatures of gelatinization.
ABSTRACT Rice bran stabilization reduces normal peroxidase, lipoxygenase and auto-oxidation enzym... more ABSTRACT Rice bran stabilization reduces normal peroxidase, lipoxygenase and auto-oxidation enzymatic activities. Depending on the stabilization treatment, lipolytic enzymes may be reversibly inhibited through partial or permanent denaturation. For effective rice bran stabilization, the treatment should inactivate the lipolytic enzymes and minimize decomposition of bioactive components. The objective of this study was to evaluate the effects of an acetic and propionic acid mixture on the proximal composition, colorimetric profile, gross energy, lipid acid and lipid oxidation products (K232, K270) in rice bran during storage. Whole rice bran treated with organic acids and stored for 120 days exhibited lower quality. However, no major proximal composition alterations were observed during storage or related to organic acid use. Furthermore, organic acids yielded the highest gross energy values, lower lipid acidity increases, less primary (K232) and secondary (K270) lipid oxidation product formation, and maintenance of the yellow color (value ‘b’) after storage for 120 days. This study shows that applying an acetic and propionic acid mixture conserves the bran well, which primarily supports its use for treating animal feed.
Soybean is a rich source of bioactive compounds, such as phenolic acids, flavonoids, isoflavones,... more Soybean is a rich source of bioactive compounds, such as phenolic acids, flavonoids, isoflavones, carotenoids, and tocopherols. The amount of bioactive compounds in freshly harvested soybeans and their derived products has been determined; however, when they are used in the food industry, soybeans are generally stored prior to being processed. This study aimed to evaluate the effects of soybean moisture content (12%, 15%, and 18%) and storage temperature (11, 18, 25, and 32 °C) on the free phenolic, total flavonoid, vanillic acid, total carotenoid, and δ- and γ-tocopherol content of soybeans stored for 12 mo. Moreover, the ABTS and DPPH radical scavenging activities of phenolic extracts were determined. There was an increase in free phenolics and total flavonoids in the stored grains compared with the grains on the 1st d of storage. Vanillic acid showed a decrease in soybeans stored at 15% and 18% moisture content and 25 or 32 °C, which indicated some degradation into other metabolites. Total carotenoid content decreased as a function of storage temperature and showed some temperature-dependent degradation. The δ- and γ-tocopherol content also tended to decrease in grains stored at 15% or 18% moisture content or 25 or 32 °C, regardless of the moisture content studied.
ABSTRACT The aim of this study was to evaluate the effects of utilizing an eolic exhauster on red... more ABSTRACT The aim of this study was to evaluate the effects of utilizing an eolic exhauster on reducing the qualitative losses of rice stored in silos. Paddy rice was stored for a nine-month period, in triplicate, in metal silos with a 550-ton capacity that were or were not equipped with an exhauster system and were analyzed every three months. To evaluate the effects of complementary eolic aeration, the energy consumed for aeration and the physical properties of the grain, as well as the thermal and pasting properties of rice, were analyzed. Using the exhauster system in the rice storage silo reduced the loss of dry matter, the energy required for aeration maintenance over a 9-month period, grain hardening, the development of grain staining defects and the darkening of the grain, while preserving the conclusion temperature of gelatinization and the enthalpy, the final viscosity and the head rice yield and not affecting the onset temperature or the peak temperature of gelatinization. Increasing the duration of storage reduced the aeration maintenance requirement, changed the cooking time, the hardness of the grains, the conclusion temperature and the enthalpy, the peak viscosity and final viscosity, the head rice yield, the development of grain staining and the darkening of rice grains, but with less intensity when the rice was stored in silos that used an exhauster system, without affecting the onset and peak temperatures of gelatinization.
ABSTRACT Rice bran stabilization reduces normal peroxidase, lipoxygenase and auto-oxidation enzym... more ABSTRACT Rice bran stabilization reduces normal peroxidase, lipoxygenase and auto-oxidation enzymatic activities. Depending on the stabilization treatment, lipolytic enzymes may be reversibly inhibited through partial or permanent denaturation. For effective rice bran stabilization, the treatment should inactivate the lipolytic enzymes and minimize decomposition of bioactive components. The objective of this study was to evaluate the effects of an acetic and propionic acid mixture on the proximal composition, colorimetric profile, gross energy, lipid acid and lipid oxidation products (K232, K270) in rice bran during storage. Whole rice bran treated with organic acids and stored for 120 days exhibited lower quality. However, no major proximal composition alterations were observed during storage or related to organic acid use. Furthermore, organic acids yielded the highest gross energy values, lower lipid acidity increases, less primary (K232) and secondary (K270) lipid oxidation product formation, and maintenance of the yellow color (value ‘b’) after storage for 120 days. This study shows that applying an acetic and propionic acid mixture conserves the bran well, which primarily supports its use for treating animal feed.
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