Effect of different temperatures and embedding media on flower dehydration of zinnia (Zinnia linearis Benth.)

Increased temperature reduced per cent moisture content in flowers, which in turn, increased reduction in size and ultimately lead to rapid drying. Although flower shape was maintained at all the temperatures after optimum level of dehydration, the overall quality was found better at lower temperature (40°C) with better retention of colour. Flower longevity was found dependent on per cent moisture content wherein moisture content ranged between 8 to 11.5% provided six month shelf-life, while moisture content below 8% lead to petal shedding. Among embedding media, drying with sand provided good quality of dried flowers with attractive flower colour and smooth petaltexture but required more drying duration. On the other hand, drying in silica gel was faster without any deterioration in quality. It showed good quality of dried flowers with appealing colour but exhibited slight roughness in petal texture (aesthetically acceptable). Thus, dehydration at 40°C with sand for 30 h duration or with silica gel for 24 h were found to be effective techniques for dehydration of zinnia flowers.