Casey Anthony: First Taste of Freedom -- Beer!

Casey Anthony hit the bottle minutes after being released from jail ... TMZ has learned.

TMZ has seen video of Casey getting off a private jet in Florida, hours after she ended her stint behind bars. The video shows Casey holding a half-empty Corona beer bottle.

Casey is smiling as she deplanes. Her former lawyer, Todd Macaluso, is also on board. At one point Casey is heard saying, "I concur" -- a little legalese she probably picked up from her legal team.

Laughter erupts as someone screams, "De Plane, De Plane."