Project snapshot: Enhancing hempseed oil cake protein through fermentation

This report examines how fermentation can increase the value of hempseed oil cake, a by-product of hempseed oil production. Australia’s hemp industry continues to grow, and processors need new ways to use this protein-rich material.

However, hempseed oil cake often delivers limited value because its protein is less soluble and harder to digest.

To address this challenge, researchers tested solid-state fermentation with three food-safe microorganisms: Bacillus subtilis, Lactobacillus rhamnosus and Aspergillus niger.

The team optimised fermentation conditions and measured changes in protein quality. Fermentation increased soluble protein levels and produced large numbers of small peptides.

Laboratory testing showed strong antioxidant activity and effects on enzymes linked to blood pressure, blood sugar control and brain health.

The researchers also used advanced peptide analysis, digestion studies and computer modelling to identify key bioactive peptides. Several peptides remained stable after simulated digestion and showed the potential to support health-related functions.

These findings provide a practical pathway for turning a low-value by-product into a premium ingredient. Processors could use fermented hempseed oil cake in functional foods, nutrition products and high-quality animal feeds. Different starter cultures created different peptide profiles, which may suit different market needs.

The process uses little water and relatively low energy. It can support value-adding, sustainability and new income opportunities across the Australian hemp industry.