HISTORY / LORE:
A First Fruit Offering is the return of a portion of something gained to the deity responsible. This is usually food or drink but it can also be other things as well: return of a portion of the proceeds from an art work to Athena, from a craft to Hephaistos, from a scientific discovery to Apollo, from a court judgment to Zeus, etc. Food and drink offerings are most often to Demeter and Dionysos. Demeter was sometimes referred to as the goddess with the great loaves due to the Thargelos (loaves of barley bread) sacrificed to her. (No, Really!)
The First Fruit Offering can be left at a Herme or other sacred spot to be taken by the needy. It can be buried or burnt at a low altar to appease evil spirits (Keres) or as sacrifice to the chthonic deities. Or it can be cooked on an above ground altar and shared with the Olympian deities. The most important concept is that, as a sacrifice, it can never be returned to the giver.
First Fruit Offerings are sometimes added to an animal sacrifice to become part of the feast and, sometimes, even replaced the animal sacrifice in cases of poverty or vegetarianism. In the later case, the animal sacrifice is replaced with loaves of bread or cakes shaped like the animal. Since what is sacrificed cannot be returned, the excess from the feast or burnt offerings are given to the priest(ess) to dispose of as they will (including personal consumption).
Fasting is sometimes done before the food sacrifice to symbolize the agricultural process (you eat less while the plants are growing so you can feast at the harvest). However, at all such sacrifices, one should keep in mind the fundamental principle of "Nothing to excess". Always sacrifice when you can afford it and never impoverish yourself by sacrifices.
SOURCES:
- Burkert, Walter (1985) Greek Religion. Cambridge, Mass.: Harvard University Press
- Cooper, J.C. (1990) The Dictionary of Festivals. Hammersmith, London: HapersCollinsPublishing
- Nilsson, Martin (1940) Greek Folk Religion. Philadelphia, PA: University of Pennsylvania Press