Effect of extrusion processing on the soluble and insoluble fiber, and phytic acid contents of cereal brans

• Published in: Plant foods for human nutrition (Dordrecht) Vol. 51; no. 3; pp. 187 - 198
• Main Authors: Gualberto, D.G. (Soft Wheat Quality Lab. USDA-ARS, Wooster, OH (USA).), Bergman, C.J, Kazemzadeh, M, Weber, C.W
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer 1997
• Subjects: ACIDE PHYTIQUE; ACIDO FITICO; Analysis of Variance; ARROZ; Avena - chemistry; AVENAS; AVOINE; Biological and medical sciences; BLE; BRAN; Cereal and baking product industries; Dietary Fiber - analysis; DIETARY FIBRES; Edible Grain - chemistry; EXTRUSION; FIBRA DE LA DIETA; FIBRE ALIMENTAIRE; Food Handling - instrumentation; Food Handling - methods; Food industries; Fundamental and applied biological sciences. Psychology; OATS; Oryza - chemistry; PHYTIC ACID; Phytic Acid - analysis; RICE; RIZ; SALVADO; SON; TRIGO; Triticum - chemistry; WHEATS; Cereal bran; Dietetic product; Correlation analysis; Antinutrient factor; Content; Plant fiber; Rotation speed; Extrusion; Dietary fiber; Phytic acid; Operating conditions; Extruded product
• ISSN: 0921-9668; 1573-9104
• DOI: 10.1023/A:1007941032726

The health benefits associated with dietary fiber have resulted in it now being used in virtually all food product categories, including many products which are manufactured using extrusion processing. The objective of the present study was to determine if extrusion processing affected phytic acid, and soluble and insoluble fiber contents. The effect of screw speeds of 50, 70, and 100% of maximum rotations per minute (% MRPM) on these components was investigated. A BI-EX Model DNDG-62/20D co-rotating intermeshing self-cleaning twin-screw extruder, manufactured by Bühlerag, CH-9240, Uzwil, Switzerland, was used to process wheat, oat and rice brans. It was found that extrusion did not affect the insoluble fiber content of wheat bran; however, a decrease in this component was observed in rice and oat brans. The effect on rice bran insoluble fiber was greatest at screw speeds of 50 and 70% MRPM. This occurred in oat bran at 50% MRPM. Soluble fiber content increased in all brans after extrusion, except ER100. For oat and rice bran soluble fibers, the greatest increase occurred at 50 and 70% MRPM, while for wheat bran this occurred at 70 and 100% MRPM. Extrusion did not affect the phytate content of the cereal brans.