Processing Optimization of Production of Hydrolyzed Protein from Orange Seed Waste with Pepsin Enzyme

Background and Objectives: The results of observations and studies over the years have shown that health and nutrition are highly related with each other. Bioactive peptides are defined as hydrolyzed proteins, which have the ability to stimulate the desired activities. In this study, the effect of adding pepsin enzyme on orange seed protein was investigated to obtain the hydrolyzed protein, and the antioxidant properties of the hydrolyzed protein were evaluated.  Materials & Methods: In the present study, the orange seed protein concentrate was extracted, and then hydrolyzed using different concentrations of pepsin enzyme (1- 3% W/W) and the hydrolysis time of (2-5 hours) at the temperature range of 45-55 °C. Optimal conditions for production of hydrolyzed proteins with the highest antioxidant properties (DPPH radical scavenging activity, radical OH scavenging activity, ferric reducing activity, and total antioxidant) were evaluated. Results: Optimum treatment at determined conditions (temperature 33 °C, time 4 hr and enzyme to substrate ratio of 2.35 %w/w) with antioxidant properties (DPPH radical scavenging activity (59/63%), radical OH scavenging activity (48/12%), ferric reducing activity (57/83%) and total antioxidant (87/59%) was obtained, and antioxidant tests were performed on the optimal treatment for confirmation of the values proposed by software. Conclusion: The results showed that the hydrolyzed protein derived from orange seed could be used in formulation of foods as a natural additive with the antioxidant ability. It can also be used as a nutraceutical.