擠壓米產品之品質指標及生育醇含量評估   全文下載

Evaluation on Quality Indices and Retained Tocopherol Contents in the Production of the Rice-Based Cereal by Extrusion

米糠是糙米的最外層含有豐富的維生素E、膳食纖維、礦物質及油脂，本研究即利用糙米或精白米為主原料，經由雙軸擠壓機製造膨發休閒食品，其原料水分分別為15及20%，螺軸轉速為200及250 rpm，進行探討產品理化特性以求得最適加工條件，並進一步分析生育醇之殘存量。結果顯示，含糙米之擠壓食品在顏色分析上有較高之a、b值，膨發度及溶解度亦較由精白米製造之擠壓食品高；相反的，L值、表密度及吸水性指標則較低，且由糙米製造得到之擠壓食品有較高之α- 及γ- 生育醇含量（4.8及5.7μg／g）。由15%原料水分及250 rpm 螺軸轉速會得到膨發度與溶解度較高及表密度較低之產品。

Rice bran is rich in vitamin E, dietary fiber, mineral and fat. In this study, puffed rice ball was made from brown or milled rice flour by using twin-screw extruder. Two feed moisture (15 and 20%) and two screw speed (200 and 250 rpm) were set, and the physicochemical properties and content of α-, β-, γ-, and δ-tocopherols were determined. The data showed that extrudates made from brown rice had a high a and b value in color, expansion ratio, water solubility index, but low in L value, bulk density and water absorption index than that made from milled rice flour. Extrudates made from brown rice flour had the higher content of α- and γ- tocopherols (4.8 and 5.7 μg/g). Regarding the effects of feed moisture and screw speed of extruder, the data showed that 15% feed moisture in flour and 250 rpm screw speed yielded to a high expansion ratio, high water solubility index, and low bulk density in the final products. 米糠是糙米的最外層含有豐富的維生素E、膳食纖維、礦物質及油脂，本研究即利用糙米或精白米為主原料，經由雙軸擠壓機製造膨發休閒食品，其原料水分分別為15及20%，螺軸轉速為200及250 rpm，進行探討產品理化特性以求得最適加工條件，並進一步分析生育醇之殘存量。結果顯示，含糙米之擠壓食品在顏色分析上有較高之a、b值，膨發度及溶解度亦較由精白米製造之擠壓食品高；相反的，L值、表密度及吸水性指標則較低，且由糙米製造得到之擠壓食品有較高之α- 及γ- 生育醇含量（4.8及5.7μg／g）。由15%原料水分及250 rpm 螺軸轉速會得到膨發度與溶解度較高及表密度較低之產品。