Standardization of dehydration techniques of some selected flowers

Floriculture has become a promising industry in modern urbanization acquiring even larger space day by day. The decorative value of flowers lead to their use of vase decoration, bouquets, arrangement for gift, as well as decoration of home, parks, gardens, work places, etc. However, due to the perishable nature of the flowers their vase-life is too short. Often it becomes cumbersome for the urban people to take proper care due to shrinkage of time. Consequent upon this, dehydrated flowers and foliages have established potentiality as a substitute for fresh flowers and foliages for interior decoration along with other artistic and commercial purposes. The main characteristics of dry flowers include novelty, longevity, aesthetics, flexibility and year round availability. Different drying techniques can be adopted, but main aim should be the production of quality materials in respect of shape, color, texture and freshness. In the present investigation flowers like Chrysanthemum morifilium 'Korean Yellow', sunflower (Helianthus annus 'Daisy') and Coreopsis tinctoria 'Roulette' were subjected to drying condition viz. room temperature (25-30°C), hot air oven (45-50°C) and microwave oven (180°C). Desiccants comprising of sand, sawdust, silica gel, sand-boric acid (1:1) and sawdust-boric acid (1:1) were evaluated. Methods utilized in the present experimental set up were air drying, press drying and embedding. Overall 17 treatment combinations were evaluated. Optimum duration for each of the treatments were worked out and standardized. In Chrysanthemum morifilium 'Korean Yellow', early effective drying was observed with silica gel embedded method of drying for 45 s in microwave oven condition and was observed to be superior in terms of retention of color, form and texture. In sunflower (Helianthus annus 'Daisy'), dry flowers casting brightness for color and intact firm petals yielded from silica gel embedded method under room temperature condition for five days. In the flower of Coreopsis tinctoria 'Roulette', optimum drying was observed when the flowers lost 68-69% moisture when embedded in silica gel under hot air oven condition for 9 h, however, silica gel-microwave oven treatment exhibited better quality of dried flowers. Overall, it may be inferred that silica gel embedded drying technique under microwave condition after optimization of time period for drying of the said flower may yield better results over others.