Production of soy protein isolate - carboxymethylcellulose conjugate through ‎non-thermal plasma

The aim of the present study was to investigate the possibility of the soy protein isolate-carboxy methylcellulose conjugate via non-thermal plasma. Therefore, a 1: 1 mixture of soy protein isolate and carboxymethylcellulose was treated with DBD plasma for 5, 10 and 15 min under the voltages of 16, 18, and 20 kV. Then, the solubility, Emulsifying activity and emulsion stability, the average particle size of the emulsion, the glycation degree, the Fourier transform infrared spectrum (FTIR), and the electrophoretic pattern of the resulting complexes were investigated. The results of electrophoresis, FTIR, and glycation degree proved the formation of soy protein isolate-carboxymethylcellulose conjugate after plasma treatment. The amount of conjugate formation depends on voltage and time of plasma treatment. The resulting conjugates had significant solubility and emulsifying activity compared to the mixture of these two compounds (p <0.05). The smallest droplet size of emulsion was observed in 18 kV treatment for 5 min, which has better stability over time compared to the mixture of soy protein-carboxymethyl cellulose. In general, it can be said that the non-thermal plasma process is able to rapidly form a protein-polysaccharide conjugate with a very good emulsifying ability.