Optimized enzymatic synthesis of the food additive polyglycerol polyricinoleate (PGPR) using Novozym® 435 in a solvent free system

Polyglycerol polyricinoleate (PGPR) is used as an emulsifier in the food industry, especially in chocolate coatings and chocolate bars. PGPR improves the characteristics of molten chocolate by reducing yield stress, facilitating the coating of confectionery pieces, while limiting the amount of cocoa butter involved.The enzymatic synthesis of PGPR catalyzed by lipases presents several advantages over chemical synthesis, including enzyme specificity and the mild conditions needed, thereby avoiding undesirable side-reactions and by-products. A novel process to synthesize PGPR using a biocatalyst, Novozym® 435, is presented. Novozym® 435 is appropriate for catalyzing both the reactions involved in this process. A PGPR fulfilling European specifications for this food additive as well as recommendations set out in the Food Chemical Codex, was obtained using a discontinuous vacuum reactor with a dry nitrogen flow. In addition, the biocatalyst reuse would decrease costs. Moreover, it was confirmed that the ability to obtain PGPR in a one-step reaction significantly shortens the time required.