2014 Annual Meeting Abstract - An indirect rapid heat moisture treatment method in improving functionality of whole wheat flour

Poster Presentation
Whole grain

182-P

An indirect rapid heat moisture treatment method in improving functionality of whole wheat flour
M. KHAMIS (1), J. Wilson (2), H. Dogan (3)
(1) Kansas State University, Manhattan, KS, U.S.A.; (2) USDA ARS, Manhattan, KS, U.S.A.; (3) Kansas State Univ, Manhattan, KS, U.S.A.

Native starch is generally modified by physical, chemical, biological or their combination to improve functionality. However increasing numbers of consumers are demanding food processing technique with minimal inclusion of additives. Heat moisture treatment and annealing are two commonest physical methods used to modify starch. However, these methods require a longer treatment time that lasts several hours, a hindrance for commercial. In this research we investigated use of rapid indirect heat moisture treatment technique to improve starch functionality. 3000 lbs of wheat was divided in two portions. Half was heat treated then milled into whole wheat flour, while the other half was first milled into whole wheat flour then heat traded. Both whole grain and whole wheat flour were subjected to indirect heating in continuous system at 15 combinations of residence times (30-90s), hydration levels (12-20%) and temperatures (75-95°C) that enabled us to produce flours with varying functionality. Treated grain milled to whole wheat flour using a Buhler 202 mill to obtain straight grade flour and obtained bran ground further using a Fritz mill. The treated flours were examined for physicochemical changes to starch using RVA (pasting properties), DSC (degree of gelatinization), gel permeation chromatography (GPC), X-ray diffraction, swelling, solubility and particle size analysis. Treated samples had low peak vs (2610 vs 1353cP), breakdown (919-385cP), final viscosity (3357-1871cP) properties, crystallinity (23.9-12.1%), and higher solvent retention capacity for sucrose (105 vs 127%), sodium carbonate (86-107%) and lactic acid (91-96%) compared to control samples. Moisture content and temperature were found to be the most significant processing factors. These effects were more pronounced in treated whole wheat flour compared to treated whole wheat grain.