Sumantudharmasutra 1.7: Smṛticandrikā · Madanapārijāta · Nirṇayasindhu +2

1.7

pākābhāve 'dhikāraḥ syād viprādīnāṃ narādhipa | apatnīnāṃ mahābāho videśagamanādibhiḥ || sadā caiva tu śūdrāṇām āmaśrāddhaṃ vidur budhāḥ

In the absence of cooked food, O king, there is entitlement [to an uncooked offering] for brahmins and others, / for those without wives, O mighty-armed one, due to travel abroad and other causes; / and the wise know that for shudras the uncooked ancestral rite is always [prescribed].

O king, the uncooked śrāddha is for Brahmins and the rest when cooking is impossible, for those without wives, for those abroad and the like, and always for Śūdras: so the wise know.