Effect of Pre-drying Treatments and Microwave Drying Duration on Quantitative and Qualitative Attributes of Dried Rose Flowers

Abstract

Roses, known as the “Queen of Flowers,” are highly valued ornamental crops but their short post-harvest life necessitates effective preservation techniques like optimized drying methods to maintain quality and extend usability. A laboratory investigation was conducted to standardize pre-drying treatments and microwave drying duration for improving the aesthetic and commercial value of dried rose flowers. Four pre-drying treatments viz, control (P0), 0.5% citric acid for 15 min (P1), glycerol:water (1:3) for 24 h (P2) and 10% magnesium chloride for 4 h (P3) were combined with three microwave drying durations viz. 2.5 min (D1), 3.5 min (D2) and 4.5 min (D3). Significant variation was observed for most quantitative and qualitative traits. Glycerol-water (1:3) recorded maximum weight after treatment (11.37 g), maximum dry flower weight (5.72 g), minimum moisture loss (49.09%), maximum dry flower diameter (3.46 cm), minimum change in diameter (0.80 cm), minimum percent change in diameter (18.96%), minimum shrinkage ratio (1.25), and highest scores for brittleness (4.03), texture (3.87), colour (4.05) and shape (4.38). Among drying durations, 3.5 min produced superior qualitative quality, while 2.5 min retained higher dry weight and lower shrinkage. The best treatment combination was P2D2 for overall quality. The study revealed that glycerol pre-treatment with optimized microwave drying can produce superior dried rose flowers for value addition and commercialization.