Bio-based 2,3-butanediol production from pectin-processing side streams

Overview

This technology is a bio-based production platform that converts fiber-rich, wet, acidic side streams from pectin processing into 2,3-butanediol (2,3-BDO), a versatile platform chemical used in the manufacture of polymers, solvents, fuels, and other industrial products. The process repurposes low-value agricultural processing residues into a high-value renewable chemical, supporting circular bioeconomy goals and offering food processors a path to monetize waste streams.

By adapting an established aqueous processing platform to pectin side streams, the technology eliminates the need for energy-intensive drying and enables direct valorization of the wet feedstock as received.

Technical specifications

Process steps:

• Hydrothermal pretreatment and enzymatic hydrolysis release fermentable sugars from the fiber components of the side stream
• Combined sugar streams are fermented using the thermophilic and alkaliphilic bacterium Bacillus licheniformis YNP5-TSU
• Non-sterile fermentation and lower-cost nutrient formulations are evaluated to reduce processing costs
• Product recovery, mass balance, and water balance are assessed to define the full process economics

Demonstrated performance:

• Prior work on brewer's spent grain achieved 126.3 g of 2,3-BDO per kg of dry feedstock
• High-yield fermentation demonstrated under both sterile and non-sterile conditions

Planned validation activities:

• Feedstock characterization and optimization of pretreatment and hydrolysis to maximize sugar recovery while minimizing water and chemical inputs
• Fermentation performance quantified in controlled stirred-tank bioreactors, including titer, yield, productivity, and sugar utilization
• Techno-economic analysis integrating process data to identify major costs, value creation, and requirements for commercial scale-up

Technology readiness level

The platform has been validated at laboratory scale on fibrous food-processing side streams, with successful demonstration of sugar release and conversion to 2,3-BDO. A planned 12-month validation project will extend this to pectin-processing side streams, covering feedstock characterization, pretreatment and hydrolysis optimization, bioreactor fermentation studies, product recovery, and techno-economic analysis. This places the technology at TRL 3–4, with a defined roadmap toward pilot-scale demonstration and commercial implementation.