The study published in the International Journal of Food Science & Technology investigated the impact of an enzymatic pre-treatment on oat bran, ahead of the bread-making process.
Many approaches to improve the quality of fiber-enriched bread like fermentation and addition of enzymes have already been studied, the researchers said. However, within the research on enzymes, they said the enzymatic action was simultaneous with the bread-making process, prompting a need to look at pre-treatment options.
The study used oat bran containing 15% beta-glucans and the enzymatic hydrolysis was done using a commercial food grade cellulolytic and glycosidic enzyme mixture.
“Results suggest that the enzymatic treatment allows [the addition of a] high level of soluble fiber (more than 5%) to the flour without worsening the dough properties during both mixing and leavening,” they said.
The pre-treatment of fiber, therefore, should be considered by millers to enhance wheat milling by-products and to increase their range of products.
The use of pre-treated fiber would also minimize the problems associated with the direct use of enzymes in bread-making, which needs a scientific approach beyond the knowledge of some bakers, the researchers said.
Impact on fiber and bread-making?
However, the enzymatic treatment caused a disintegration of the fiber particles leading to a lower total fiber content in the ingredient, the researchers said.
The soluble and insoluble dietary fiber ratio also changed significantly. Soluble dietary fiber and soluble residue content increased as did the sugars.
Despite this, when it came to dough functionality, the pre-treated fiber was an improvement to regular fiber, the researchers said.
While water absorption and development time of the flour both increased, these times were less than regular fiber.
The use of pre-treated fibers also allowed a faster, better dough development than regular fiber, the research found, “likely due to the sugar formation promoted by the enzymatic treatment”.
Source: International Journal of Food Science & Technology
Published: January 2014, Volume 49, Issue 1, pages 305-307. Online ahead, doi: 10.111/ijfs.12293
“Dietary fibre enzymatic treatment: a way to improve the rheological properties of high-fibre-enriched dough”
Author: A. Marti, G. Bottega, MC. Casiraghi, F. Faoro, S. Iametti and MA. Pagani