Valorisation of multiple components from residual biomass for food and biofuel applications : A virtual biorefinery evaluation

A conceptual biorefinery process has been designed for the integration of the protein extraction and the ethanol production from brewers’ spent grain (BSG) and palm kernel meal (PKM). The conceptual process is designed for an industrial scale biorefinery annually processing 20 kton dry weight BSG and 50 kton dry weight PKM with 8000 production hours per year and is used to techno-economically analyse the performance. The techno-economic analysis showed that the biorefinery of BSG has a high economic potential with an internal rate of return of 24 %. However, despite the high raw material costs, the biorefinery of PKM still has a positive internal rate of return of 12 %. The presented virtual biorefinery demonstrated the economic potential of integrating the production of a valuable product, like protein powder for food applications, with the production of biofuel, like ethanol, from the remaining biomass, thereby valorising a larger portion of the biomass with the same raw material costs

Valorisation of proteins from palm kernel meal

A process to extract proteins from palm kernel meal was investigated. A sequence of unit operations was implemented and optimized in order to ensure an optimal process efficacy. It has been determined that among all the enzymes that were tested, Alcalase had the highest capacity to hydrolyse proteins and solubilize them in solution, especially after using 5% dry matter of PKM as a starting material. Thus, 80% of the proteins were solubilized in the supernatant after Alcalase treatment, but only 60% of the proteins were recovered in the permeate after applying ultrafiltration (300 kDa), with a purity of 60%. Functionality tests revealed that the protein fraction obtained had a very high solubility and a mild foaming and emulsification capacity