Optimizing drying techniques for Capsicum chinense: impacts on physicochemical, functional, and bioactive properties

• Microwave drying preserved bioactive retention of phenolics and heat-sensitive compounds • Nutrient retention depends on drying method optimization for antioxidants and vitamins • Microwave drying improved oil holding, while sun drying enhanced water holding This study investigated the effects of three drying methods—sun drying, oven drying (50°C), and microwave drying (300 watts)—on the physicochemical and antioxidant properties of Capsicum chinense (Chinese pepper). Fresh samples, both green and red, were analyzed post-drying for moisture content, ash content, pH, and antioxidant characteristics, including total phenolic content (TPC), DPPH radical scavenging activity, and vitamins A, B1, and B2, and C. Results demonstrated significant variation in nutritional and antioxidant properties based on drying method and pepper maturity. Microwave drying of red peppers retained the highest TPC (317.22 mg GAE/g dry matter) and Vitamin C content (317.56 mg/100 g dry matter), indicating its efficiency in preserving phenolic and heat-sensitive compounds. Oven-dried red and green peeper exhibited the DPPH activity of 87.89% and 83.13%, respectively, reflecting their superior radical scavenging potential. Microwave drying enhanced swelling capacity and oil holding capacity, whereas sun drying preserved higher water holding capacity. These functional metrics have direct industrial relevance: higher WHC/SC support rehydration and viscosity development in dry mixes and instant sauces; higher OHC benefits spice blends and emulsified systems; lower a w improves shelf stability and transport efficiency.