Dados do Trabalho

Título

RHEOLOGICAL PROPERTIES OF WHEAT DOUGH WITH ADDED TRANSGLUTAMINASE ENZYME (TGase)

Introdução

Dough is the most important intermediate stage in the transformation of cereals into various products and is essentially composed of flour and water. Chemical agents or cross-linking enzymes, such as TGase, have been reported to improve dough handling properties and to increase fermentation stability, and loaf volume. This study aimed to evaluate the effect of adding two concentrations of TGase (85 ppm and 140 ppm) on the rheological properties of white wheat (FTB) dough compared to a control without enzyme addition.

Material e Métodos

The rheological attributes of wheat dough were analyzed using a ThermoScientific Haake rheometer, model MARS iQ Air. The parallel plate geometry was selected as the testing probe, and strain sweep tests were conducted to identify the linear viscoelastic region. The target strain was set at 0.1%. Frequency sweep measurements from 0.1 to 100 Hz and temperature sweep measurements from 20ºC to 80ºC at 1 Hz were performed.

Resultados e Discussão

In all wheat doughs, it was found that the elastic modulus (G') was higher than the viscous modulus (G''), indicating a firm and elastic behavior. Due to its ability to induce isopeptide cross-linking, TGase was expected to affect the wheat protein structure and, consequently, its viscoelastic properties. This was reflected by the increase in G' and G'' values. Higher values of G' indicate that tougher or more difficult-to-deform dough samples are formed. The G' values for the samples showed the following behavior: FTB_140ppm TGase > FTB_85ppm TGase > FTB. In the temperature sweep tests, the samples exhibited a phase transition, with a sharp increase in G' and G'' at the following temperatures: FTB (60.99ºC) > FTB_85ppm (55.66ºC) > FTB_140ppm (49.13ºC). At the transition temperatures, the samples showed the following G' (Pa) values: FTB (342,400 Pa) < FTB_85ppm (517,061 Pa) < FTB_140ppm (571,649 Pa). While at 80ºC, the G' values jumped to: FTB (1.6x10^6 Pa) < FTB_85ppm (2.1x10^6 Pa) < FTB_140ppm (2.6x10^6 Pa).

Conclusão

In conclusion, a more cohesive dough structure is formed in the samples with higher TGase concentration, indicating the enzyme's potential to alter the dough's rheological properties and its application in the baking industry.