|
|
DisplayTitle
Page Content
Waxy wheat extrusion: new possibilities for expanded cereal products
R. J. KOWALSKI (1), C. F. Morris (2), G. M. Ganjyal (1). (1) Washington State Univ, Pullman, WA, U.S.A.; (2) USDA ARS, Pullman, WA, U.S.A.
Soft white waxy wheat (Waxy Pen) was analyzed for its thermal and rheological properties, and extruded to understand its processing characteristics since no extrusion data of waxy wheat has been previously reported. Normal soft white wheat flour was analyzed using the same methods to compare differences between the two types and to identify benefits of waxy wheat flour in extrusion processing. Waxy wheat was found to have a higher gelatinization temperature than normal wheat although the transition required less energy. Waxy wheat flour also pasted much quicker and at lower temperatures than the normal wheat. Preliminary extrusion experiments were conducted to determine the optimal screw profile for waxy wheat. The optimal screw profile was then used for extrusion trials with varying flour moisture (15-25% wb) and extruder screw speed (200-400 rpm) while monitoring process conditions. Radial expansion ratios of the waxy wheat extrudates exceeded that of the normal wheat extrudates and it was observed that the waxy wheat flour required less mechanical energy to expand rapidly. Radial expansion ratios for the waxy wheat ranged 1.5 to 2 times greater than the normal wheat. The waxy wheat extrudates also exhibited significantly higher water solubility and lower water absorption than the normal wheat extrudates. The results of our study indicate that waxy wheat flour may be a viable ingredient for creating direct expanded products using less energy, improving expansion of minimally expanded products, and aid in the creation of novel extruded foods.
View Presentation |
|
|
|
|
