Triacylglycerol Containing Medium-Chain Fatty Acids: Comparison of Human Milk and Infant Formulas on Lipolysis during In Vitro Digestion

Abstract

Medium-chain triacylglycerol (MCT) is widely used in infant formulas (IFs) to provide medium-chain fatty acids (MCFAs) for infants with special fat absorption requirements. However, MCFAs naturally present in human milk are medium-and long-chain triacylglycerols (MLCTs). This study investigated the effect of triacylglycerol containing MCFAs (MLCT vs MCT) on lipolysis by comparison of human milk and IFs containing 0, 20, 30, and 55% of MCT (IF 1 to IF 4) using an in vitro digestion model. Rabbit gastric lipase showed an extent of digestion within the expected range, and was selected as the alternative to human gastric lipase. All IFs showed a lower lipolysis degree compared with human milk. There was no significant difference (p = 0.175) among IFs supplemented with MCT at the end of intestinal digestion. In addition, the digestion of IFs with different MCT contents led to different free fatty acid profiles, which may have health effects on infants.

Comparative Analysis of Lipid Digestion Characteristics in Human, Bovine, and Caprine Milk Based on Simulated In Vitro Infant Gastrointestinal Digestion

“…In addition, bovine and caprine milks released more MCFAs than human milk. MCFAs can be hydrolyzed rapidly and absorbed by the intestine in the form of FFAs, which then directly enter the portal venous system and are transported to the liver for β-oxidation and used as a fast energy source. , Therefore, when producing infant formulas, we should consider not only that the fatty acid composition should be close to that of human milk but also the similarity of the TAG structure to be an essential component to consider infant formulas in the future.…”

Glycerol Monocaprylate Modulates Gut Microbiota and Increases Short-Chain Fatty Acids Production without Adverse Effects on Metabolism and Inflammation

“…GMC, as a typical glycerol derivative of MCFAs, could be hydrolyzed to caprylic acid and glycerol by lipase in the intestine. It is known that GMC has a long residence time in the intestinal tract, and both GMC and its hydrolytic acid (octylic acid) have antibacterial properties [ 7 ]. Hence, GMC may significantly influence the gut microbiota.…”

Impact of Dietary Lipids on the Reverse Cholesterol Transport: What We Learned from Animal Studies

“…Moreover, MCFA can also be found as medium- and long-chain TG in human milk fat, representing a fast energy source as they are rapidly absorbed, oxidized, and digested. For this reason, milk formulas for preterm infants are usually enriched in MCFA for up to 50% of the total fat content [ 70 ]. Indeed, ingested MCFA, mainly caprylic acid and capric acid, have limited potential for storage as TGs: they are poorly incorporated into chylomicrons and rapidly enter hepatic mitochondria, where they are immediately oxidized to acetyl-coenzyme A, and subsequently converted into ketone bodies [ 71 ].…”