Chyme

Chymeorchymus(/kaɪm/; fromGreekχυμόςkhymos, "juice") is the semi-fluid mass of partly digested food that is expelled by thestomach, through thepyloric valve, into theduodenum(the beginning of thesmall intestine).
Chyme results from the mechanical and chemical breakdown of abolusand consists of partially digested food, water,hydrochloric acid, and variousdigestive enzymes. Chyme slowly passes through the pyloricsphincterand into the duodenum, where the extraction ofnutrientsbegins. Depending on the quantity and contents of the meal, the stomach will digest the food into chyme in some time from 40 minutes to 3 hours.With apHof approximately 2, chyme emerging from the stomach is very acidic.The duodenum secretes ahormone,cholecystokinin(CCK), which causes thegall bladderto contract, releasing alkalinebileinto the duodenum. CCK also causes the release of digestive enzymes from thepancreas. The duodenum is a short section of the small intestine located between the stomach and the rest of the small intestine. The duodenum also produces the hormonesecretinto stimulate the pancreatic secretion of large amounts ofsodium bicarbonate, which then raises pH of the chyme to 7. The chyme moves through thejejunumand theileum, where digestion progresses, and the non-useful portion continues onward into thelarge intestine. The duodenum is protected by a thick layer ofmucusand the neutralizing actions of the sodium bicarbonate and bile.
At a pH of 7, the enzymes that were present from the stomach are no longer active. The breakdown of any nutrients still present is byanaerobic bacteria, which at the same time help to package the remains. These bacteria also help synthesizevitamin Bandvitamin K, which will be absorbed along with other nutrients.
Chyme has a low pH that is countered by the production ofbile, which helps the further digestion of food. Chyme is part liquid and part solid: a thick semifluid mass of partially digested food and digestive secretions that is formed in thestomachand small intestine during digestion. Chyme also contains cells from the mouth and esophagus that slough off from the mechanical action of chewing and swallowing.
After hours of mechanical and chemical digestion, food has been reduced into chyme. As particles of food become small enough, they are passed out of the stomach at regular intervals into the small intestine, which stimulates thepancreasto release fluid containing a high concentration ofbicarbonate. This fluid neutralizes the gastric juices, which can damage the lining of the intestine and result induodenal ulcer. Other secretions from the pancreas,gallbladder,liver, andglandsin the intestinal wall help in digestion, as these secretions contain a variety ofdigestive enzymesand chemicals that assist in the breakdown of complex compounds into those that can be absorbed and used by the body.
When food particles are sufficiently reduced in size and composition, they are absorbed by the intestinal wall and transported to the bloodstream. Some food material is passed from the small intestine to thelarge intestine. In the large intestine, bacteria break down any proteins and starches in chyme that were not digested fully in the small intestine.
When all of the nutrients have been absorbed from chyme, the remaining waste material changes into semisolids that are calledfeces. The feces pass to therectum, to be stored until ready to be discharged from the body duringdefecation.
The chyme of anunweanedcalf is the defining ingredient ofpajata, a traditionalRoman recipe.
Chyme is sometimes used inPinapaitan, a bitterIlocanostew.