紅薏仁吸水特性及對烹煮品質的影響

Water Absorption Characteristics of Adlay and Its Influence of Cooking Quality

何珮華(Pei-Hua He) ； 江伯源(Po-Yuan Chiang)

《臺灣農業化學與食品科學》 52卷1期 (2014/02) Pp. 15-24

https://doi.org/10.6578/TJACFS.2014.003

摘要

紅薏仁為薏苡籽實經去殼末精白之種仁，其營養成分豐富，並具多種機能性功能，成為近年保健研究的重要原料。由於紅薏仁質地堅硬、難煮，浸漬是加工前的重要步驟，但因浸漬耗時甚長，了解其吸水特性及對其烹煮品質影響一直是加工業者長期以來有待解決的問題，本試驗以紅薏仁為原料，探討各項吸水特性及對烹煮品質之影響，試驗結果如下：隨浸漬時間延長，溫度提高，紅薏仁之吸水率、體積膨脹率、固形物溶出率及浸漬液混濁度均呈現增加變化，硬度則呈下降趨勢。另藉由浸漬時間和溫度可得函數關係t=46593T^(-1.314)（t：浸漬時間；T：浸潰溫度）（r^2=0.99），進而得知其活化能（Ea）為27.01 ＂kJ/mole＂。以60℃浸漬四小時，可縮短烹煮時間及得到較高接受性之口感，浸漬可使水分滲入，可溶性成分溶出，因此由微細構造中，可見紅薏仁組織由緻密轉呈鬆散，另烹煮紅薏仁可觀察到澱粉顆粒轉成糊化網狀的構造。藉由本試驗結果，可提供紅薏仁加工業者作為控制浸漬條件及品質改進之參考。

關鍵字

紅薏仁 ； 浸漬 ； 吸水動力學 ； 硬度 ； 微細構造

並列摘要

The adlay is the seed of ＂Coix lacryma-jobi＂ which is shelled but not refined. Adlay is abundant in nutritious and functional properties which make it important in recent healthy food research. Because the texture of adlay is hard and it is hard to cook, soaking becomes the most important step before processing. However, soaking of adlay takes much time. The water absorption characteristic and its influence of cooking quality has become a big issue for a long time. In this study, we used adlay as a material to discuss water absorption characteristics and the effects of soaking on cooking quality of adlay. The results showed that water absorption ratio, swelling ratio, solid dissolution rate, and turbidity of soaking solution increased and hardness decreased with increasing soaking time and temperature. In this study, we obtained an equation: t=46593 T^(-1.314) (t: soaking time, T: soaking temperature, r^2=0.99) and the activation energy (Ea) was calculated as 27.01 ＂KJ/mole＂. We also found that soaking at 60°C for 4 hours can shorten the cooking time and get better taste. For microstructures, soaking makes soluble components dissolve and loosens the structure. In addition, cooking transtorms the starch structure from a particle form to a net form via gelatinization. We hope that the results can be used as references for the adlay industry to improve the soaking condition and quality.

並列關鍵字

adlay ； soaking ； water absorption kinetics ； hardness ； microstructure