Innovative cold plasma modification of Caulerpa prolifera proteins: A strategy to improve techno-functional and antioxidant properties

In this study, the effects of cold plasma (CP) on structural, techno-functional, and antioxidant properties of Caulerpa prolifera proteins were investigated for the first time. C. prolifera proteins were modified by CP to improve their techno-functional and antioxidant properties. CP conditions (power: 5, 47.5, 90 W; treatment time: 1, 15.5, 30 min; pressure: 30, 60, 90 Pa) were optimized to determine the effect of CP on water absorption capacity (WAC),oil absorption capacity (OAC), emulsion activity (EA), emulsion stability (ES), foaming capacity (FC), foaming stability (FS), free sulfhydryl group (SH) content, protein solubility (PS), and antioxidant activity (AOA) of the proteins extracts and functional groups, microstructure, color, and nutritional properties of the modified proteins were investigated. Optimum conditions were 87.50 W power, 6.63 min treatment time, and 90 Pa pressure. At optimum conditions, WAC, OAC, EC, ES, FC, FS, Free-SH content, AOA DPPH , AOA CUPRAC , and PS were 232.04 ± 10.25 g/hg, 350.66 ± 15.78 g/hg, 49.50 ± 5.05 g/hg, 49.95 ± 0.51 g/hg, 101.26 ± 7.89 g/hg, 70.10 ± 2.85 g/hg, 18.28 ± 1.50 mmol/kg, 3.78 ± 0.40 g Trolox equivalent (TE)/kg, 8.31 ± 0.01 g TE/kg, and 22.30 ± 4.02 g/hg, respectively. The findings showed that CP provided an increase in WAC, AOA, and PS of proteins and the results were confirmed by investigating changes in secondary structure of proteins. • Techno-functionality of Caulerpa prolifera proteins greatly improved by cold plasma (CP). • The proteins exhibited notable structural changes as a result of CP treatment. • The essential amino acid score nearly doubled, reflecting an improvement in nutritional quality. • Following CP treatment, there was an obvious increase in the browning index.