Post Harvest Management of Horticultural Crops

Tinting

Artificial colouration of flowers is called tinting. It is applied through

a. stem (carnation)
b. dipping the flowers heads (daisies)

a. Tinting via stem - is done with adding food grade dye solution with appropriate chemicals in a bucket of warm water of 410C. The carnation flowers to be tinted (usually white coloured) are allowed to stress overnight in packing house at 180C to increase the rate of solution uptake. Dying is stopped before the flowers reach the desired colour, because dye still in the stem is flushed into the flowers by vase solution.
b. Dipping – is carried through tinting solution containing aniline dyes dissolved in isopropanol. The head of the flowers are dipped in a dye solution and shaken to remove surplus solution and placed on a rack to dry before storage or packing.


Fig. Artificial coloration in flower carnation