Vaishnava Dharmashastra 81.21

81.21

yāvad ūṣmā bhavaty anne yāvad aśnanti vāgyatāḥ
tāvad aśnanti pitaro yāvan noktā havir guṇāḥ //

Having brought together (the remainder of) all the sorts of substantial food and (of the vegetables and) the like, he must sprinkle it with water, and place it before the Brâhmanas, who have taken their meal, strewing it on the ground.