It is permissible to eat or drink while in the state of janabah (major ritual impurity). However, before eating or drinking, one should rinse the mouth and wash the hands. Eating or drinking without rinsing the mouth is considered makruh tanzihi.
Additionally, if a person drinks something without first rinsing their mouth, only the first sip is considered makruh. The mouth is purified after this first sip, so the sips that follow are not considered makruh.