Effect of microwave assisted convective drying on physical properties, bioactive compounds, antioxidant potential and storage stability of red bell pepper

Abstract

Current study was aimed to optimize the process conditions for microwave assisted convective drying of red bell pepper (RBP) by employing Response Surface Methodology (RSM). Responses analyzed for determining the optimum conditions were total phenolics, vitamin C, antioxidant activity, color change, non-enzymatic browning (NEB), rehydration ratio and firmness. Second order polynomial model was fitted to the experimental results and high values of R2 (>0.8) were noticed in all responses. The optimal drying conditions were determined to be 62.44 °C and 418.84 W. Furthermore, separate experiment was carried out at these derived optimum conditions for ensuring the appropriateness of models. A close similarity among experimental and predicted values indicated the fitness of the model for determining the quality characteristics of RBP. Prolonged storage of RBP, however, led to the reductions of some quality attributes, although remained stable and acceptable at the end of six months storage.

Keywords

• Red bell pepper
• Response surface methodology
• Microwave assisted convective drying
• Optimization
• Storage stability