Laudator Temporis Acti

Scholion on Lucian, Lives of the Courtesans 2.1 = Scholia in Lucianum, ed. Hugo Rabe (Leipzig: B.G. Teubner, 1906), pp. 275-276, tr. in Aristophanes, Thesmophoriazusae. Edited with Introduction and Commentary by Colin Austin and S. Douglas Olson (Oxford: Oxford University Press, 2004), p. xlix, with notes (the festival was the Thesmophoria):

When Kore was snatched by Plouton as she was gathering flowers, a certain swineherd named Eubouleus was tending pigs in the same place and they were swallowed up by Kore's chasm. Therefore in honour of Eubouleus piglets are thrown into the chasms belonging to Demeter and Kore. And the rotting [remains] of them, after they have been thrown down into the megara (lit. 'great halls'),³⁷ are brought up by women called 'drawers', who have stayed pure for three days and who go down into the aduta ('innermost sanctuaries') and, after they have brought them up, set them on the altars. They believe that whoever³⁸ takes some of these and mixes them in with his seed-corn will get an abundant crop.

³⁷ Cf. Paus. ix.8.1 (of ceremonies in a 'sacred grove' of Demeter and Kore at Potniae in Boiotia): 'at a fixed time ... they let go some new-born pigs into the so-called megara (ἐν χρόνῳ δὲ εἰρημένῳ ... ἐς τὰ μέγαρα καλούμενα ἀφιᾶσιν ὗς τῶν νεογνῶν).

³⁸ Note the masculine participles, which seem to imply that men were allowed to approach the altars when the festival was over.

There are some simpler recipes in Ellen Churchill Semple, "Ancient Mediterranean Agriculture: Part II. Manuring and Seed Selection," Agricultural History 2.3 (July, 1928) 129-156.