Skandapurana 6.3.11.29

6.3.11.29

amṛtaṃ brāhmaṇasyānnaṃ kṣatriyānnaṃ payaḥ smṛtam .
vaiśyānnamannameva syācchūdrānnaṃ rudhiraṃ smṛtam .. 11.29 ..

The food of a brahmin is considered nectar; the food of a kṣatriya is remembered as milk; / the food of a vaiśya is merely plain food; the food of a śūdra is considered blood.