From The Food Encyclopedia by Jacques Rolland and Carol Sherman
Also crystallized flowers. Fresh, edible flowers, such as violets, rose petals or scented geraniums, that have been painted with a mixture of egg white and water, then sprinkled with sugar. The sugared flowers are then left to dry until firm, at which point they are basically nonperishable and can be kept at room temperature for quite a while. The sugar gives the flowers a frosted appearance and preserves their form for use on cakes and fancy desserts.
