Śatapatha Brāhmaṇa ("of a hundred paths") 2.3.1.14

2.3.1.14

taddugdhvādhiśrayati | śṛtamasaditi tadāhuryarhyudantaṃ tarhi juhuyāditi tadvai nodantaṃ kuryādupa ha dahedyadudantaṃ kuryādaprajajñi vai reta upadagdhaṃ tasmānnodantaṃ kuryāt

Having milked he puts that (milk) on (the Gârhapatya fire), because it has to be cooked. Here now they say, 'When it rises to the brim, then we shall offer it!' He must not however let it rise to the brim, since he would burn it, if he were to let it rise to the brim; and unproductive indeed is burnt seed: he must not, therefore, let it rise to the brim.