1 Esophageal peristalsis results from sequential contraction of circular muscle, which serves to push the ingested food bolus toward the stomach. 2  Esophageal longitudinal muscle may also play a role in peristalsis.he main function of the esophagus is to propel swallowed food or fluid into the stomach. This occurs through sequential or peristaltic contraction of circular muscle in the esophageal body, in concert with appropriately timed relaxation of the upper and lower esophageal sphincters.