gastric digestion


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Related to gastric digestion: digestion

digestion

 [dĭ-jes´chun]
1. the subjection of a substance to prolonged heat and moisture, so as to soften and disintegrate it.
2. the act or process of converting food into chemical substances that can be absorbed into the blood and utilized by the body tissue.
 Digestion. 1. Carbohydrates: principally starches, lactose, and sucrose. Starches are acted on by the enzyme ptyalin (alpha-amylase) secreted in saliva, by hydrochloric acid (HCl) in the stomach, and by pancreatic amylase and intestinal amylase in the small intestine, which split the starches into maltose and isomaltose. These, in turn, are acted on by maltase and isomaltase and split into two molecules of glucose. Lactose is split by the enzyme lactase into a molecule of galactose and a molecule of glucose. The monosaccharides glucose, galactose, and fructose are absorbed from the small intestine into the blood. 2. Fats: emulsified by bile salts and agitation. The emulsified fats are acted upon by pancreatic and enteric lipase to form fatty acids, glycerol, and monoglycerides, which are absorbed through the intestinal walls. Small quantities of diglycerides and triglycerides are also absorbed. 3. Proteins: acted on chiefly in the stomach by pepsin, which splits proteins into proteoses, peptones, and polypeptides. In the small intestine they are acted on by the pancreatic enzymes trypsin, chymotrypsin, and carboxypeptidase to form polypeptides and amino acids. In the small intestine the peptidases complete the breakdown of the peptides into dipeptides and amino acids. Almost all proteins are eventually digested and absorbed either as amino acids or as dipeptides or tripeptides.
See illustration. Digestion is accomplished by physically breaking down, churning, diluting, and dissolving the food substances, and also by splitting them chemically into simpler compounds. Carbohydrates are eventually broken down to monosaccharides (simple sugars); proteins are broken down into amino acids; and fats are absorbed as fatty acids and glycerol (glycerin). The digestive process takes place in the alimentary canal or digestive system. The salivary glands, liver, gallbladder, and pancreas are located outside the alimentary canal, but they are considered accessory organs of digestion because their secretions provide essential enzymes.
gastric digestion digestion by the action of gastric juice.
digestion/hydration in the omaha system, a client problem defined as converting food into substances suitable for absorption and assimilation into the body and supplying water to maintain adequate body fluids.
intestinal digestion digestion by the action of intestinal juices.
pancreatic digestion digestion by the action of pancreatic juice.
peptic digestion gastric digestion.
primary digestion digestion occurring in the gastrointestinal tract.
salivary digestion the change of starch into maltose by the saliva.

gas·tric di·ges·tion

that part of digestion, chiefly of the proteins, carried on in the stomach by the enzymes of the gastric juice.
Synonym(s): peptic digestion

gas·tric di·ges·tion

(gas'trik di-jes'chŭn)
That part of digestion, chiefly of the proteins, carried on in the stomach by the enzymes of the gastric juice.
Synonym(s): peptic digestion.

gas·tric di·ges·tion

(gas'trik di-jes'chŭn)
Stage of digestion, chiefly of proteins, carried on in the stomach by enzymes of gastric juice.
References in periodicals archive ?
Number of peptides identified from Red Chittagong Cattle milk proteins at different stages of ex vivo digestion Protein G20 G40 D5 D120 [[alpha].sub.s1]-CN 15 12 13 02 [[alpha].sub.s2]-CN 04 04 07 01 [beta]-CN 36 35 40 31 [kappa]-CN 10 08 03 -- [beta]-Lg 01 01 03 05 G20, Gastric digestion for 20 min at pH 5; G40, Gastric digestion for 20 min at pH 2.5; D5 and D120, Duodenal digestion for 5 and 120 min, respectively at pH 7; CN, Casein; Lg, lactoglobulin.
Several in vitro methods of estimating feed digestibility have been developed, and can be divided into single-(AOAC, 1980; Mertz et al., 1984), two- (Babinszky et al., 1990; Cone and van der Poel, 1993), or three-step (Vervaeke et al., 1979; Boisen and Fernandez, 1991) models simulating the gastric digestion, the gastric/small intestinal digestion and the gastric/small intestinal/large intestinal digestion, respectively.
Dynamic in vitro model for measuring in digestability : The dynamic model simulating gastric digestion in pigs was constructed using the LabView (Ver.
Gastric digestion is a key process in whole gastrointestinal tract digestion and absorption because it is alters the chemical and mechanical properties of the diet which affects the digestion and absorption in all other GI compartments.
In the present study, we determined these parameters in a controlled environment of diet and water intake to establish a dynamic model for simulating the pigs' gastric digestion and compared protein digestibility to that observed in vivo and to those protein digestibility estimates derived from a commonly used static in vitro model.