A team of researchers has used X-ray microtomography to assess how varying amounts of salt affects bubble formation and dough-handling properties in bread dough.

The scientists from the University of Manitoba found that reduced salt created a stickier dough, which has implications in large-scale processing when dough sticks to machinery, but this could be mitigated with stronger wheat cultivars, higher water contents and shorter mixing times.

Along with a team of colleagues, Dr. Filiz Koksel, an Assistant Professor of food and nutritional sciences at the university, has used the CLS synchrotron (The Canadian Light Source) at the University of Saskatchewan to explore how a call for reduced sodium in bakery products affects the billions of tiny bubbles that help make bread such an appealing food.

The research stems from Health Canada recommendations that Canadians reduce the amount of sodium in their diets. “Among all foods, bread and bread products contribute about 30 per cent of this excess consumption,” Koksel said. The researched aimed “to see if it is easy to reduce sodium and to identify processing challenges related to using less salt.”

“Bread-making is part art and part science,” said Dr. Filiz Koksel, an assistant professor of food and nutritional sciences at UM. The art stems from the bakers’ deft touch with dough, but the science is “about what’s happening with ingredients.”

“The key to commercially produced bread is the crumb or texture that is created by an even distribution of uniform-sized bubbles throughout the dough,” Koksel explained.

“Consumers of commercial breads are said to like consistency, meaning no big holes. In contrast, bakers of artisan breads like French baguettes strive for bubbles of varying size. “Bread can be up to 80 per cent air by volume.”

In the end, all the variables tested require adjustment when salt is reduced to ensure good-quality non-yeast low-sodium bread, but using the optimal mixing time was of particular interest.

“During mixing, three critically important tasks are taking place,” said Koksel.

“First, mixing blends and hydrates the ingredients. It’s also critical to developing gluten proteins in the wheat, and to incorporating air bubbles into the dough. Mixing also affects the dough handling properties. Reducing sodium can end with a good result if water, the wheat cultivar and mixing are all optimised.

“Additional changes to bread formulations such as increasing fibre or reducing other additives will require similar evaluations because with each change we’re facing new processing and product quality challenges.”