Author
SANDHU, HARKANWAL - North Dakota State University | |
MANTHEY, FRANK - North Dakota State University | |
SIMSEK, SENAY - North Dakota State University | |
Ohm, Jae-Bom |
Submitted to: Meeting Abstract
Publication Type: Abstract Only Publication Acceptance Date: 7/22/2013 Publication Date: 7/22/2013 Citation: Sandhu, H., Manthey, F.A., Simsek, S., Ohm, J.B. 2013. Ozone gas affects the physical and chemical properties of wheat (Triticum aestivum L.) starch. American Association of Cereal Chemists International Annual Meeting, September 29-October 2, 2013, Albuquerque, NM. Available: http://www.aaccnet.org/meetings/documents/2013abstracts/2013pab203.htm Interpretive Summary: Technical Abstract: Ozone can oxidize hydroxyl groups present at C2, C3, and C6 positions on the starch molecule and affect its physicochemical properties. In this experiment, bread wheat flour and isolated wheat starch were treated with ozone gas (1,500 ppm, gas flow rate 2.5 L/minutes) for 45 minutes and 30 minutes, respectively. Starch was isolated from treated flour. Ozone treated starch and starch isolated from ozone treated flour had similar chemical and physical properties. Chemical analysis of starch isolates indicated depolymerization of high molecular weight amylopectins, with a subsequent increase in low molecular weight starch polymers as a result of starch hydrolysis. Ozone oxidized starch isolates resulting in elevated levels of carboxylic groups and a decrease in total carbohydrate content in amylopectin fractions. 1H NMR results indicated formation of a keto group [(1'4)-3 keto] at the H-2 terminal (proton at C-2 position) and ß-glucuronic acid at the H-1 terminal (proton at C-1 position). DSC transition temperatures and change in enthalpy were not affected by ozone treatment. Increased swelling power and RVA breakdown (peak viscosity – hot paste viscosity) were observed in starch from ozone treated samples. |