What if a common by-product from sunflower oil could help turn everyday bread into a nutritional win? That’s exactly what Brazilian researchers explored, and the answer appears to be yes, with some trade-offs.
A new study published in ACS Food Science & Technology shows that partially defatted sunflower seed flour (SF), a leftover from industrial oil extraction, can be used to increase protein, fiber and antioxidant levels in bread. The sunflower seed flour contains as much as 66% protein along with dietary fiber, iron, calcium and chlorogenic acid, a powerful antioxidant linked to anti-inflammatory and blood sugar-regulating effects.
“Reusing this by-product adds nutritional value to bread and reduces the environmental impact of the sunflower oil industry,” said lead author Leonardo Mendes de Souza Mesquita, a biologist at the University of São Paulo. “In addition, sunflower seed flour is an extremely cheap raw material, which the oil industry sells just to avoid disposing of it as waste.”
In the study, researchers swapped out portions of wheat flour (WF) with sunflower seed flour in varying amounts, from 10% to 60%. Breads with higher percentages of SF showed major nutritional gains, including more than triple the protein content and a big jump in antioxidant activity, but also became denser and firmer in texture.
That’s where a simple solution comes in: adding sunflower flour’s aqueous extract (SFE) helped retain the light, soft texture of traditional bread.
“This indicates that adding SFE is an effective strategy for maximizing the nutritional benefits and minimizing the adverse sensory effects,” Mesquita said.
The work supports a broader goal: using food industry by-products to improve health and reduce waste.
“Transforming waste into products is a fundamental strategy for promoting a circular economy,” Mesquita said.
The research was supported by the São Paulo Research Foundation through six funded projects and a Young Researcher Grant.