Quality and Dehydration Kinetics of Zinnia Elegans L. Cut Flowers in Relation to Drying Duration and Embedding Media

Present investigation was undertaken to standardize dehydration techniques for Zinnia elegans L. and to evaluate the quality characteristics of dehydrated flower products. Freshly harvested flowers were subjected to different dehydration methods, with detailed drying kinetics evaluated using a hot air oven at 50°C with two embedding media, namely washed fine river sand and florist grade silica gel, at drying durations of 0, 4, 8, 12, 16, 20, and 24 hours. The study assessed flower dry weight, cumulative moisture loss, moisture content, drying rate, dimensional shrinkage, pigment stability, and overall visual quality. Silica gel embedding at 50°C accelerated moisture removal, with optimum dehydration achieved within approximately 16–18 hours. In comparison, river sand provided better physical support and minimized distortion of ray florets, although a longer drying period of approximately 24 hours was required to attain equilibrium moisture levels. The optimum structural texture, with adequate flexibility and minimal petal brittleness, was achieved at approximately 80–83% moisture loss, corresponding to an equilibrium moisture content of about 4.4–5.3%. The drying data indicated that flower weight loss and moisture reduction followed second order polynomial and exponential decay patterns with increasing drying time. Overall, hot air oven dehydration using suitable embedding media proved effective for producing structurally stable and visually acceptable dried Zinnia flowers. The standardized drying protocol provides a practical basis for converting seasonal Zinnia flowers into value-added dry floral products suitable for potpourri, resin crafts, floral arrangements, and other decorative applications.