Exploring the use of ultrafiltration-diafiltration for the concentration and purification of mealworm proteins

This work aimed to study the performance of the UF-DF process, in terms of the permeation flux and membrane resistance, to produce a mealworm protein isolate. Moreover, a detailed characterization of the UF-DF retentates and permeates was performed. The results showed that the UF performances was reduced during the concentration phase, with a total flux decline close to 40 %. The membrane fouling was mainly reversible, and the flux was totally recovered during the DF. As expected, the ash content was drastically reduced in the retentate, but interestingly, low effects on the soluble sugars and lipids contents were noticed. The UF permeates were mainly composed of free amino acids and low molecular weight peptides, which confirms a high protein rejection of the UF membrane. Finally, compared to the protein concentrate before the UF-DF (57.29 %), the protein content increased by 26.4 % to reach 72.40 % which validates the feasibility of producing mealworm protein isolates using filtration parameters described in this work. This study demonstrated the potential of using UF-DF to produce a mealworm protein isolate with a complete amino acid profile rich in essential amino acids.