Journal of Food, Agriculture and Environment

Vol 10, Issue 1,2012
Online ISSN: 1459-0263
Print ISSN: 1459-0255

Effect of okra extract on properties of wheat, corn and rice starches


Mohammed S. Alamri 1, Abdellatif Mohamed 1*, Shahzad Hussain 1, Jingyuan Xu 2

Recieved Date: 2011-09-17, Accepted Date: 2012-01-14


Seedless okra pods were extracted with 0.05 M NaOH. The extract was centrifuged and the supernatant and the precipitate were freeze-dried. Size exclusion high pressure chromatography showed that the supernatant contained peptides covalently bound to the sugars. Wheat, corn and rice starch blends were prepared by replacing 0, 5, 10 and 15% of the starch with dried supernatant (DSP) or dried precipitate (DPP). The effect of DSP and DPP on starch properties was determined by rapid visco-analyser (RVA), gel texture analysis and dynamic rheology. The presence of DSP significantly (p≤0.05) reduced the peak temperature of starch compared to 100% starch. The DPP containing samples exhibited significantly higher peak viscosity due to the presence of more cellulose. Similar effect was observed on the setback of all starches. Starch-gel firmness was significantly reduced by DSP. Although corn starch showed the highest gel firmness value, it had the highest drop in firmness, whereas wheat starch showed a linear reduction in firmness compared to corn starch. The reduction in gel firmness is due to two factors, the replacement of starch and the action of the DSP. The reduction in gel firmness was found to be 39% for 15% wheat starch replacement. All test frequencies showed that starches exhibited G’ higher than G”. The elastic moduli (G’) of wheat starch reached a plateau about 1360 Pa, while the phase shifts were in the range of 5º – 17º. Corn starch showed slightly weaker viscoelastic solid properties compared to wheat starch with a G’-plateau around 1120 Pa, and phase shifts range between 5º and 16º, while rice starch was the weakest. These variations are due to the starch granule structure and the amylose/amylopectin ratio.


Okra gums, soluble fiber, suspension rheology, starch gels, corn, rice, wheat

Journal: Journal of Food, Agriculture and Environment
Year: 2012
Volume: 10
Issue: 1
Category: Food and Health
Pages: 217-222

Full text for Subscribers

Note to users

The requested document is freely available only to subscribers/registered users with an online subscription to the Journal of Food, Agriculture & Environment. If you have set up a personal subscription to this title please enter your user name and password. All abstracts are available for free.

Article purchasing

If you like to purchase this specific document such as article, review or this journal issue, contact us. Specify the title of the article or review, issue, number, volume and date of the publication. Software and compilation, Science & Technology, all rights reserved. Your use of this website details or service is governed by terms of use. Authors are invited to check from time to time news or information.

Purchase this Article:   20 Purchase PDF Order Reprints for 15

Share this article :