Effect of Acylglycerol Composition and Fatty Acyl Chain Length on Lipid Digestion in pH‐Stat Digestion Model and Simulated In Vitro Digestion Model

Abstract In this study, a pH‐stat digestion model and a simulated in vitro digestion model were employed to evaluate the digestion degree of lipids depending on different acylglycerols and acyl chain length (that is, diacylglycerol [DAG] compared with soybean oil representing long‐chain triacylglycerol compared with medium‐chain triacylglycerol [MCT]). In the pH‐stat digestion model, differences were observed among the digestion degrees of 3 oils using digestion rate ( k ), digestion half‐time ( t 1/2 ), and digestion extent (Φmax). The results showed the digestion rate order was MCT > soybean oil > DAG. Accordingly, the order of digestion half‐times was MCT < soybean oil < DAG. In simulated in vitro digestion model, digestion rates ( k ′) and digestion half‐times ( t ′ 1/2 ) were also obtained and the results showed a digestion rate order of MCT ( k ′ = 0.068 min −1 ) > soybean oil ( k ′ = 0.037 min −1 ) > DAG ( k ′ = 0.024 min −1 ). Consequently, the order of digestion half‐times was MCT ( t ′ 1/2 = 10.20 min) < soybean oil ( t ′ 1/2 = 18.74 min) < DAG ( t ′ 1/2 = 29.08 min). The parameters obtained using the 2 models showed MCT was digested faster than soybean oil, and that soybean oil was digested faster than DAG.