May 2026
The global sulfur market is in turmoil. Record-high prices, constrained supply chains, and unprecedented volatility have left corn wet millers facing a difficult question: how do we maintain yields while managing skyrocketing SO₂ costs?
For an industry that has relied on sulfur dioxide for decades, the answer may lie in an unexpected place—enzymes.
Why Corn Wet Milling Depends on SO₂
Sulfur dioxide has been a workhorse for corn steeping for good reason. It performs critical functions:
- Breaking disulfide bonds in the protein matrix and softening the corn kernels — This releases starch granules from the kernels’ protein network, directly increasing starch yields, and increases the permeability of the kernels to help promote hydration, which helps soften the kernels for milling and separation.
- Controlling microbial growth — The antimicrobial properties of SO₂ help keep bacterial contamination in check during the lengthy steeping process.
Most facilities operate with SO₂ concentrations between 1,500 and 2,000 ppm—levels that have been standard practice for generations.
The Problem with SO₂ in 2026
Supply and Cost PressuresThe sulfur market disruptions of early 2026 have pushed SO₂ costs to historic highs. Processors who once treated sulfur as a minor line item are now watching it consume an outsized share of operating budgets.
Environmental and Health Concerns
Beyond economics, SO₂ carries regulatory and reputational baggage. It’s classified as a respiratory hazard and environmental pollutant, drawing increasing scrutiny from regulators and sustainability-focused customers alike.
Proteases: A Practical Alternative
Protease enzymes offer a compelling path forward. These enzymes break down the same protein matrix that SO₂ targets—but through hydrolysis.
What the Data Shows
Facilities using proteases have reported:
- Significant reductions in SO₂ usage, with some operations eliminating it entirely
- Comparable or improved starch yields compared to traditional steeping
- Significantly reduced process time, improving throughput and capacity utilization
Process Adjustments Required
Switching to protease-assisted steeping isn’t a drop-in replacement—it requires process modifications:
- Initial steep of corn kernels
- Coarse milling of corn to expose the endosperm
- Steep of coarsely ground corn with added protease enzyme
While there are more steps and multiple steeping steps, the total processing time is significantly shorter. This translates to faster batch turnover and reduced working capital tied up in work-in-progress inventory.
The Bottom Line
With sulfur markets showing no signs of stabilization, proteases represent more than a cost hedge—they’re a strategic investment in process resilience. The combination of reduced input costs, improved yields, and shorter cycle times creates a compelling business case, even before factoring in the environmental and regulatory benefits.
Interested in exploring protease solutions for your operation?
Contact EDC for technical guidance and application support tailored to your facility’s specific requirements.