Functionality of rice flour modified with a microbial transglutaminase

Abstract:

Rice flour is one of the most valuable cereal flours from a nutritional viewpoint. However, its use is limited to unfermented baked products since rice proteins are unable to hold gas produced during fermentation. Protein functionality can be modified by cross-linking. Rice flour was treated with different concentrations of a microbial transglutaminase (TG). The extent of the modification was evaluated by quantifying amino and thiol groups. The addition of TG improved the dynamic rheological properties of rice flour doughs, resulting in a progressive increase of the viscous (G″) and elastic (G′) moduli with increase in TG concentration. The improvement in rice protein functionality became evident in breadmaking, since it was possible to obtain rice bread with an increased specific volume and softer crumb at 1% TG level in the presence of 2% hydroxypropylmethylcellulose. Analyses showed that rice proteins are polymerised through the TG reaction, providing a protein network necessary for holding the gas produced in fermentation. © 2003 Elsevier Ltd. All rights reserved.

Año de publicación:

2004

Keywords:

• Transglutaminase
• Dynamic rheology
• bread
• Protein cross-linking
• Rice proteins

Fuente:

scopus