Stabilized phycocyanin blue pigment from cyanobacteria for food and beverage applications

Overview

Natural blue colorants are in high demand across the food and beverage industry, but many plant- and algae-derived blue pigments suffer from poor stability when exposed to heat, acidity, or light. Phycocyanin, the vivid blue pigment-protein complex produced by cyanobacteria, is one of the few intense natural blue colorants available, but it typically loses its color above 50 °C and at low pH, which has limited its commercial adoption.

This technology addresses that bottleneck through a food-compatible encapsulation process that protects the phycocyanin complex without introducing chemical crosslinkers or other modifications that would be undesirable in a food additive. The result is a stabilized phycocyanin that retains a high color number (purity) and remains stable at 80 °C for 10–60 minutes, making it suitable for applications where conventional phycocyanin would degrade.

Technical specifications

• Core material: phycocyanin, a blue pigment-protein complex produced by cyanobacteria at roughly 20% of dry cell weight
• Stabilization approach: encapsulation of the intact pigment-protein complex using food-compatible components, with no chemical crosslinking or chemical modification of the pigment itself
• Purity: stabilized product retains a high color number, exceeding standard food-grade purity
• Thermal stability: stable for 10–60 minutes at 80 °C, compared with rapid color loss above 50 °C for unstabilized phycocyanin
• Extraction process: optimized two-step extraction yields analytically pure phycocyanin, simpler than conventional multi-step purification
• Scale characteristics: laboratory-validated process that is not strongly scale-sensitive, supporting straightforward scale-up
• Additional properties: phycocyanin is inherently tolerant to low pH and high light intensity; ongoing work is quantifying how encapsulation further improves pH and light stability

Technology readiness level

The technology has been validated at laboratory scale through numerous experimental variations of the encapsulation method, with demonstrated thermostability improvements and a simplified extraction workflow. Current efforts are focused on broadening the stabilization procedure to enhance pH and light stability for a wider range of food, beverage, and related applications. Because the extraction and stabilization steps are not strongly scale-sensitive, the process is positioned for straightforward scale-up and pilot demonstration with an industrial partner.