Sustainable Valorization of Soybean Husk via Green Extraction Technologies: Bioactive Compound Recovery and Formulation of Fiber-Enriched Scones

What if the humble soybean husk—usually discarded as waste—could be transformed into a nutritious, antioxidant-rich ingredient for your next scone?

Soybean husk, a major by-product of soybean processing, is often overlooked. Yet this study reveals its hidden potential: it packs a hefty 67.98% fiber and a moderate 10.56% protein. Researchers set out to unlock its bioactive treasures using two green extraction technologies—ultrasound-assisted extraction (UAE) and pressurized liquid extraction (PLE). While UAE showed promise with longer times and 50% ethanol, PLE stole the spotlight. At 140°C with 50% ethanol, PLE yielded 19.97% extract, boasting 17.1 mg GAE/g of total phenolics and 167.6 µmol TE/g of antioxidant capacity. Isoflavone profiling identified daidzin, genistin, and their derivatives as the main players. But the story doesn't end in the lab. The optimal extract and raw husk were baked into scones, resulting in significantly higher phenolic content and antioxidant activity (≈36 µmol Trolox/g) compared to controls. Adding the husk also boosted dietary fiber, earning the product a legitimate 'source of fiber' label. This research showcases how valorizing soybean husk via PLE can enhance the nutritional and functional quality of everyday bakery goods.

Key Points

• PLE outperforms UAE for bioactive recovery.
• Optimal extract: 19.97% yield, high phenolics and antioxidants.
• Scones with extract or husk boost fiber and antioxidant activity.