The Compendium of Bheḷa 6.4.77

6.4.77

niṣpākaś cāsya tailasya samyak siddhasya yo bhavet | udaśvidiva dadhyarthaṃ so ' pi kṛtyakaro bhavet ||

And whatever residue of this oil is obtained when it is properly prepared, / even that, like buttermilk serving in place of curds, can perform the task.