Chapter 17 · The Three Kinds of Faith · Krishna said
Bhagavad Gita 17.10 — Tamasic food
यातयामं गतरसं पूति पर्युषितं च यत्। उच्छिष्टमपि चामेध्यं भोजनं तामसप्रियम् ॥
yātayāmaṃ gatarasaṃ pūti paryuṣitaṃ ca yat | ucchiṣṭamapi cāmedhyaṃ bhojanaṃ tāmasapriyam ||
Meaning
Food that is stale, tasteless, foul-smelling, left overnight, left over by others and impure is liked by tamasic people.