Recovery of bioactive compounds from beet leaves through simultaneous extraction: Modelling and process optimization

What if the leafy tops of beets—usually tossed aside—hide a treasure trove of health-boosting compounds? Scientists just found a simple, green way to unlock them.

Beet leaves are often discarded as waste, but they're packed with bioactive compounds that could benefit the food industry. In a new study, researchers set out to recover these valuable molecules using an eco-friendly liquid-solid extraction method. Their goal: maximize the yield of total phenolic compounds (TPC), betacyanins (BC), and betaxanthins (BX) simultaneously.

First, they tested extraction at 30°C and 80°C. The results showed that longer than 60 minutes actually degraded the betalainic pigments, so timing mattered. Then, using a Plackett-Burman design, they identified temperature, ethanol concentration (%EtOH), and solid-to-liquid ratio as the most influential variables. Finally, response surface methodology helped fine-tune these factors to hit the sweet spot.

The optimal conditions were 61°C, 80% ethanol, and a 1:10 solid-to-liquid ratio. Under these, they achieved 31.7 mg gallic acid equivalents per gram of dry matter for TPC, 0.78 mg/g for BC, and 2.17 mg/g for BX. The result? A bright red-purple extract rich in phenolics—a promising, low-impact ingredient for future food applications.

Key Points

• Beet leaves valorized via green extraction
• Optimal: 61°C, 80% ethanol, 1:10 ratio
• Rich in phenolics, bright red-purple extract