Key takeaways:
- Sunflower seed flour can significantly raise protein and fiber levels in bread, but higher inclusion rates quickly create trade-offs in loaf volume and texture.
- Using an aqueous extract of sunflower seed flour preserves much of the functional benefit while maintaining bread structure closer to conventional wheat loaves.
- Because sunflower seed flour is an existing oilseed byproduct, it offers bakers a lower-cost, lower-risk route to reformulation that also supports sustainability goals.
In industrial and high-volume commercial baking, bread is among the industry’s most conservative categories, where tight margins and scale leave little room for experimentation without risking cost or consistency.
That rigidity is now under pressure. Protein targets continue to rise. Fiber intake remains a persistent concern. Sustainability expectations have moved beyond packaging and energy use and into ingredient sourcing itself. At the same time, climate volatility and geopolitical disruption are keeping wheat markets unpredictable, increasing the risk of formulations built around a single dominant raw material.
Taken together, these pressures are driving renewed interest in ingredients already present within existing food supply chains.
One of those ingredients is partially defatted sunflower seed flour – a low-value byproduct of sunflower oil production that’s largely been overlooked in mainstream baking. New research suggests it may deserve closer attention.
What really happens when sunflower flour meets bread dough
The study, published in ACS Food Science & Technology, took a refreshingly practical approach. Researchers from the University of Campinas and University of São Paulo (USP), replaced wheat flour with partially defatted sunflower seed flour at substitution levels ranging from 10% to 60%. They then evaluated the resulting breads for nutritional composition, dough behavior and finished loaf quality.
“Our aim was to optimize the reuse of sunflower seed flour considering its high protein and chlorogenic acid content,” said Leonardo Mendes de Souza Mesquita, lead author of the study and a scientific researcher at the Institute of Biosciences of the USP.
The research didn’t frame sunflower seed flour as a direct wheat replacement. Instead, it examined how far it could be incorporated before structural penalties became commercially limiting. Beyond nutritional composition, the researchers evaluated dough behavior, loaf volume, crumb structure, firmness and antioxidant activity to identify where benefits begin to clash with performance.
Sunflower seed flour brings a markedly different nutritional profile from wheat flour. According to Mesquita, “Sunflower seed flour has been shown to contain a very high percentage of protein, from 40% to 66%, as well as dietary fiber, iron, calcium and high levels of chlorogenic acid, a phenolic compound associated with antioxidant, anti-inflammatory and hypoglycemic effects.”
Those differences carried through into the finished bread. As sunflower flour inclusion increased, protein levels rose steadily. At the highest substitution level tested, protein content exceeded 27%, compared with around 8% in conventional wheat bread. Fiber content increased alongside it, allowing the breads to reach high-protein, high-fiber thresholds without the use of isolates or fortification.
Antioxidant activity increased as well. To measure this, the researchers used Trolox equivalents – a standard benchmark that compares antioxidant activity against Trolox, a vitamin E analog. In practical terms, higher Trolox values indicate a stronger ability to counter oxidative stress. Using this measure, breads containing sunflower flour showed markedly higher antioxidant activity than wheat-only controls.
“The result reinforces the potential of sunflower seed flour to promote health benefits associated with reducing oxidative stress,” Mesquita said.
The study also reported inhibition of digestive enzymes, particularly alpha-amylase, alongside more moderate inhibition of pancreatic lipase. These are laboratory findings rather than clinical outcomes, but they suggest slower breakdown of starches and fats – a signal that may be relevant for breads positioned around satiety or steadier energy release.
From a formulation standpoint, another point stands out. Sunflower oil is produced through mechanical pressing, not chemical extraction. That means the remaining flour isn’t exposed to solvent residues, simplifying regulatory positioning and ingredient messaging.
Where performance limits emerge
The nutritional gains, however, didn’t come without trade-offs. As sunflower seed flour inclusion increased, loaf volume declined and crumb firmness increased. Once substitution moved beyond roughly 20%, breads became denser, with tighter crumb structures and reduced softness.
This challenge is familiar in alternative flour formulations. Replacing wheat flour dilutes gluten, while higher fiber content alters water absorption and dough behavior. Beyond certain thresholds, structural performance deteriorates regardless of nutritional upside.
So the researchers tested a different approach, using an aqueous sunflower extract. Produced by mixing sunflower seed flour with water and filtering the solution, the extract requires no solvents or additional processing aids.
The outcome was materially different. Breads made with the extract retained much of the functional and antioxidant benefit associated with sunflower flour, while performing more like conventional wheat bread in terms of volume, crumb structure and softness.
“However, adding the aqueous extract managed to preserve the structure and texture of the breads, keeping them close to those of traditional wheat bread,” Mesquita said.
For industrial bakeries, this distinction matters. Whole sunflower seed flour may suit denser, protein-forward breads where texture expectations differ. Extracts offer a route into softer loaves where volume and crumb are non-negotiable. Blended approaches provide further flexibility.
Importantly, the ingredient is already produced at scale and the extraction process is relatively simple. Adoption wouldn’t require a fundamental overhaul of bakery operations or supply chains.
A circular economy play
The relevance lies not in novelty, but in the fact that sunflower-derived ingredients already exist at industrial scale within established supply chains.
Sunflower oil production is global, mature and industrialized. The flour left behind has limited high-value outlets and is often sold cheaply to avoid disposal. Redirecting it into food production improves resource efficiency without increasing agricultural demand.
This has implications for wheat dependence at a time when supply volatility remains a concern. Ingredients that can partially offset wheat use without introducing new sourcing risks or significant cost penalties are likely to attract interest from large-scale bakers.
From a safety and regulatory perspective, mechanical oil extraction reduces concerns around processing residues, with any contaminants linked to agricultural practices rather than manufacturing steps. As scrutiny of food processing intensifies, that distinction is increasingly relevant.
For brands trying to square health, sustainability and margin pressure all at once, that’s a rare alignment. Bakers gain access to protein and fiber at a lower cost than many alternative ingredients. Oil processors gain a higher-value outlet for an existing byproduct. Sustainability teams gain a credible circular-economy example that extends beyond packaging initiatives.
Incremental change, not reinvention
The findings don’t suggest sunflower seed flour will replace wheat in mainstream bread. Nor do they point to rapid shifts in formulation strategies.
For an industry built on consistency, that may be exactly the kind of change that sticks.
Bread doesn’t need reinvention. It needs incremental improvements that don’t scare consumers or strain operations. Sunflower oil waste, awkwardly enough, fits that brief rather well.
Study:
Leonardo Mendes de Souza Mesquita, Etiene Valeria Aguiar, Letícia S. Contieri, et al. Repurposing Sunflower Seed Flour for Nutritional and Functional High-Protein Breads within a Circular Economy Framework. ACS Food Science & Technology 2025 5 (4), 1425-1435 DOI: 10.1021/acsfoodscitech.4c01008
