Date of Graduation

8-2019

Document Type

Thesis

Degree Name

Master of Science in Food Science (MS)

Degree Level

Graduate

Department

Food Science

Advisor/Mentor

Griffiths G. Atungulu

Committee Member

Ya-Jane Wang

Second Committee Member

Terry Siebenmorgen

Third Committee Member

Andy Mauromoustakos

Keywords

Brokens, By-product, Comingling, Functional properties, Parboiled rice, Pasting property, Regular rice

Abstract

Rice flour generated from broken rice (brokens) has inconsistencies in functional properties. This may be due to differences in size and composition of brokens used for the flour. It is postulated that size classification of brokens can improve flour functionality. This study sought to investigate the effect of size fractionation of brokens on the functional or pasting properties of resulting rice flour. Broken rice was generated from six cultivars of freshly harvested rough rice that were dried at 25◦C in the laboratory. The brokens were classified into large, medium and small, using US sieve size 10, 12 and 20 respectively. Comingling of the brokens based on size was done. Pasting properties of broken rice flour were analyzed. Results indicate that, larger brokens had better pasting properties than smaller brokens. Size and cultivar of brokens had significant impacts on protein content, peak viscosity, trough viscosity, breakdown viscosity, final viscosity, setback viscosity and peak time of brokens. Rice aging influences pasting property. The moisture content (MC) of rice before parboiling affects the pasting property of the parboiled broken rice flour, thus rice parboiled at 12.5% MC (aged rice) had higher peak viscosity and final viscosity than rice parboiled at 18% MC (fresh rice). Size fractionation of brokens is essential in understanding the functionality of brokens to produce premium and high-quality products.

Share

COinS