Optimization of Drying Parameters for Maximum Nutrient Retention in Cassia auriculata: Implications for Functional Food Development

Abstract

The development of efficient drying techniques for medicinal plants while preserving their nutritional composition remains a significant challenge in food processing technology. This study investigated the impact of three distinct drying methods (solar, cabinet, and shade drying) on the nutritional composition of Cassiaauriculata leaves, buds, and flowers. Fresh samples were collected and processed following standard protocols, with dried materials ground into powder and analysed in triplicate. Comprehensive proximate analysis revealed significant variations in fat content (p<0.008) and tannins (p<0.001) across drying methods. Mineral profiling demonstrated notable differences in potassium (p=0.001), selenium (p=0.004), magnesium (p<0.001), and copper (p=0.005) concentrations among the samples. Shade-dried samples exhibited superior nutrient retention, maintaining higher levels of essential minerals including calcium (6484.57 mg/kg), potassium (11100.2 mg/kg), and magnesium (2108.95 mg/kg) compared to solar and cabinet drying methods. Additionally, shade drying preserved the highest crude fiber content (16.20%) and protein levels (12.15%). The study establishes shade drying as the optimal method for Cassia auriculata processing, achieving a 40% recovery rate while maximizing nutrient preservation. These findings provide valuable insights for the standardization of drying protocols in medicinal plant processing and have significant implications for the functional food industry.