RESUMO
An integrated approach to extraction and refining of RBO using supercritical carbon dioxide (SC-CO2) in order to preserve the nutritionally important phytochemicals is reported here. Process variables such as pressure, temperature, time, solvent flow rate and packing material on extraction yield and quality of RBO were investigated using a pilot model SC-CO2 extraction system. Three isobaric (350, 425 and 500 bar), three isothermal temperatures (50, 60 and 70 degrees C), three extraction times (0.5, 1 and 1.5h), at 40/min CO2 flow rate and three packing materials (pebbles, glass beads and structured SS rings) were employed. The RBO yield with SC-CO2 extraction increased with temperature and time under isobaric conditions. At the 60 degrees C isotherm, an increase in the RBO yield was obtained with an increase in the pressure and time. The RBO yield increased significantly with structured SS rings used as packing material. The RBO extracted with SC-CO2 had negligible phosphatides, wax and prooxidant metals (Fe and Cu) and was far superior in color quality when compared with RBO extracted with hexane. At the optimum condition of extraction at 500 bar, 60 degrees C for 1.5h, with structured SS rings used as packing material, the yield of RBO was comparable with that of hexane extraction (22.5%). The phytochemical contents of the RBO under the optimum conditions were in the range of tocols, 1500-1800 ppm; sterols, 15,350-19,120 ppm and oryzanol 5800-11,110 ppm.
Assuntos
Manipulação de Alimentos/métodos , Óleos de Plantas/química , Óleos de Plantas/metabolismo , Dióxido de Carbono/metabolismo , Ésteres , Ácidos Graxos/análise , Ácidos Graxos/química , Valor Nutritivo , Óleos de Plantas/normas , Óleo de Farelo de Arroz , Esteróis/análise , Esteróis/químicaRESUMO
Kerala is a state in India with a high prevalence of cardiovascular diseases and diabetes. In order to control these diseases, the prevalence of modifiable risk factors such as low physical activity need to be studied. For this a cross-sectional study was conducted to assess the level of physical activity among 240 residents aged between 15 and 65 years in Kulappuram, a village in north Kerala. Low level of physical activity was seen in 65.8% of the study participants. The average duration of moderate to vigorous intensity physical activity per day in different domains such as work, travel, and recreation were 40.5, 10.1, and 12.7 minutes, respectively. The average duration of sedentary activities was 284.3 minutes per day. The level of physical activity was more among those engaged in unskilled work (adjusted odds ratio = 4.32; confidence interval = 1.38-13.51) and unmarried persons (adjusted odds ratio = 3.65; confidence interval = 1.25-10.65). No statistically significant difference in physical activity level was seen in different age, education, religious, and economic categories. The study concludes that the physical activity level was low in the study population.