Use of supercritical CO₂ to improve the quality of lupin protein isolate

Lupins are an excellent source of protein which can be used to obtain protein isolates with potential use in the food industry. Some studies use supercritical CO₂ (SC-CO₂) to defat legume flours, but no study analyzes the effect of applying this technology directly to the protein isolate. This article has proposed the use of SC-CO₂ to improve lupin protein isolate (LPI) quality. SC-CO₂ increased the LPI purity while reducing oil and other antitechnological factors (saponins and polyphenols). The treatment significantly improved the LPI color due to the elimination of the lipid fraction and lipophilic pigments (carotenoids). No changes in amino acid contents or chemical score were observed due to the SC-CO₂. Finally, the treatment improved or did not affect the main LPI technofunctional properties. Therefore, SC-CO₂ is a promising technique to enhance the quality of protein isolates, without affecting or improving their functional properties.