Professor: Gluten-free baking must not forget starch
The gluten-free bakery sector has continued to grow in size and value over the past few years and as this trend snowballs, manufacturers in their masses have battled to develop the ultimate gluten-free bread, muffin or pastry.
Gluten-free and cereal grain expert Elke Arendt from the University of Cork, Ireland, said that while efforts had progressed, struggles relating to texture and dough function remained and could be aided with a better focus on starch.
“Why can’t we make a good quality bread that is gluten-free? Well, it’s not only about the gluten,” Arendt said.
During the baking process of regular bread made from wheat flour and water, she said the starch became partially gelatinized – a reaction that was not the case in gluten-free. “Usually in gluten-free, a lot more water is used – that means starch is totally gelatinized,” she explained to attendees at Fi’s Bakery Innovation Europe in Munich two weeks ago.
This total gelatinization of the starch created a completely different structure and dough behavior, she said, compared to regular wheat bread.
“People always forget the starch, they all talk about the gluten but always forget the starch.”
Getting starch right and understanding it
She said it was essential to get starches right in gluten-free and that they were equally important as the protein content.
Bakery manufacturers must understand the starch profile of flours used when producing gluten-free products, Arendt said, particularly as they varied hugely from wheat flour.
The starch in wheat, for example, was made up of very small molecules, compared to potato starches, which were considerably bigger, she explained. “The starches you find in wheat are so, so different.”
She said that use of hydrocolloids could counter-balance some of the structure impact that totally gelatinized starch gives in gluten-free. "[Hydrocolloids] give you product rheology control and organoleptic properties like mouthfeel, flavor release and higher viscosity," she said.
Water content also crucial in gluten-free
In addition to closely considering the starch in gluten-free bakery, Arendt said that manufacturers must also look closely at the water content.
“Generally in gluten-free cereals you lose a lot of water. It depends if you have a wholemeal or endosperm flour, but the water loss can be anything between 85-120%, compared to 70% in normal wheat breads,” she said.
She said that manufacturers could add fiber to the formulation to hold water.