November 28, 2006

 

Enzymatic modification to boost wheat gluten gelling

 

 

Modifying wheat gluten protein with transglutaminase enzymes improves the gelling, rheological and textural properties, claim Chinese researchers.

 

The result might offer value-added solutions for a wide range of food products.

 

Modification of the gluten protein provides an alternative for maximizing the texturisation of the proteins by TGase reaction, wrote Jin-Shui Wang in the journal "Food Hydrocolloids".

 

Studies have been performed on the effect of this enzyme on casein, soy proteins, whey proteins, myosin, and globulin earlier. The new study probes the gelling behaviour of the insoluble wheat gluten proteins, as well as the rheological and texture properties of the resulting gels.

 

The research could extend the use of wheat gluten proteins, as the latter is cheap and readily available.

 

The reason its use has so far been limited is because it lacked certain desirable functional properties, like solubility and emulsifying properties, explained Wang.

 

Wang and his team used microbial Tgase, provided by Ajinomoto to modify wheat gluten (71.5 percent protein).

 

According to researchers, the minimal concentration of the modified wheat gluten needed to form a gel was 16 percent, significantly less than the 22 percent of the unmodified wheat gluten required. Previous studied have reported that soy protein isolates and lupin seed proteins have minimum gelation concentrations of 10 and 14 percent.

 

TGase improved the gelation behaviour and gel properties of the wheat gluten, according to researchers.

 

Some modified wheat gluten is already available to food formulators, like, for example, Tate & Lyle's Meripro 410 and 420 launched earlier this year.

 

While the former provides functional benefits as an emulsifier and dough plasticiser, the latter is said to have emulsifying and foaming properties well suited for desserts and confectionery.

 

The study was funded by the National Science Foundation of China and the Doctorate Foundation of South China University of Technology.