The contents of the stomach impact alcohol's ability to get into the blood because after eating, the pyloric sphincter, which separates the stomach from the small intestine, closes.
There's also a pyloric sphincter, or valve, at the end of the stomach which closes while eating, keeping food inside for the stomach to churn over and over again.
It is a coiled long tube that winds from the pyloric sphincter of the stomach to the beginning of the large intestine, filling much of the abdominal cavity.
The cardiac sphincter relaxes and contracts to move food from the esophagus into the stomach, whereas the pyloric sphincter allows food to leave the stomach when it has sufficiently digested.
It receives chyme and gastric juices from the stomach through the pyloric sphincter, but it also imports bile from the liver and gallbladder, enzymes from the pancreas, and creates its own homegrown mix of enzymes.