6/4/2023 0 Comments Ffa in modtools![]() The increased content of FFA of rice bran without heat treatment by extrusion during the storage test in this study is similar to the results reported in other studies. Additionally, the FFA content of samples kept in the vacuum packaging was consistently higher than that in the samples without vacuum packaging over an 8-week storage period at both ambient conditions 18° C - 70 % RH and 30° C - 78 % HR ( Fig. Changes in FFA contents in samples were significant between the packing methods at both ambient conditions. The FFA content in bran extruded samples kept in a vacuum packaging was higher than those of the samples stored in laminated bags metalized without vacuum and kept at 18° C - 70 % RH for 8 weeks ( Fig. 2 and 3 it is show a constant increase in FFA levels for both packaging methods during the four-week storage period week 6 and week 8, an accelerating rate of increase of the FFA content was observed in the bran extruded and packed under vacuum and a significantly higher levels of FFA were presented in the extruded sample, packaged without vacuum when stored at 30° C - 78% RH ( Fig. Throughout the experimental period, the lower values of FFA content were observed for the extruded samples stored at 18° C - 70% RH and packaged without vacuum.įigs. The untreated rice bran showed a significantly higher increase in FFA content compared to the heat-treated rice bran extrusion, regardless of packing methods at both ambient storage conditions. The statistical analysis indicated that the packaging method showed a significant difference (p <0.05) in the content of FFA in the stored bran samples, in both raw and extruded ones, and at both ambient storing conditions. It was found that there was a difference between the two levels of each factor during storage of the samples of bran in function to the contents of FFA. Rice bran samples preserved by the procedure described above were used in other project, oriented to the development of a ready-to-eat cereal processed by the extrusion and enriched with fibers from rice and maize brans.įigure 3 Content of free fatty acids in raw rice bran (control) and packed in extruded rice bran, packaged with and without vacuum, and stored at 18° C - 70 % RH. The treated rice bran was stored for a period of two months, packed following two different packaging methods (with and without vacuum) and two ambient conditions (temperature and relative humidity). This study was conducted to determine the effect on the content of FFA resulting from any residual enzyme activity in fresh rice bran after being thermally treated by a double screw extruder and stored for a period of time under certain specific conditions. ![]() Chemical treatments have been also used to prevent rancidity of rice bran. Thermal treatments to bran rice for stabilization has been applied throw microwaving, extruding, steaming and parboiling. However, if the bran is subject to a thermal treatment of high temperature and short time immediately after polishing, the lipase activity is reduced, thus producing a bran with longer shelf life which is suitable for human consumption. Therefore, because of the biochemical instability of rice bran, occurring immediately after the polishing of rice grain, it has a short shelf life due to the decomposition of its lipids which renders it unsuitable for human consumption. After its production in the mill it undergoes rapid enzymatic hydrolysis caused by lipases activity on the bran lipids released from the cells in the milling process, which results in the decomposition of lipids into free fatty acids (FFA). ![]() Rice bran (RB) is a by-product of the rice milling process, it amounts to nearly 7-8% of the rice grain, and is a source of protein, fiber and lipids, basically unsaturated fatty acids. ![]()
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