Continuous, packed-bed, enzymatic bioreactor production and stability of feruloyl soy glycerides

Abstract The synthesis of feruloyl soy glycerides was demonstrated on a pilot-scale (1 metric ton/year) in a continuous, four-column series, packed-bed, enzymatic bioreactor (herein referred to as the bioreactor). Ethyl ferulate and soybean oil were combined and converted at 3.5 kg/d over Candida antarctica lipase B immobilized on an acrylic resin (Novozym 435) at 60 °C. The ethyl ferulate/soybean oil substrate was fed through the four, packed-bed, enzyme columns in series with each column fitted with a recirculation pump, which improved conversion and throughput compared to smaller, batch bioreactor systems. The synthesis was carried out over 4.5 months with a single charge of enzyme to produce over 450 kg of feruloyl soy glycerides at 65% conversion. The stability of the feruloyl soy glycerides was determined by comparing the total ferulate concentration (UV absorbance), free radical scavenging (antioxidant) capacity, total acid value (hydrolysis), and Lovibond color of samples produced in 2009 to samples produced in 2015. The feruloyl soy glycerides showed no appreciable loss of UV absorbing ( λ max 325 nm) or rapid antioxidant capacity (50% reduction of initial radical concentration