In-vitro method modelizing and measuring the consistency of food during its in vivo digestion

摘要

The in vitro method comprises crushing the food to reproduce the mechanical degradation operated during mastication, mixing the crushed food to a solution modeling the gastric fluid in the reactor tank coupled to a rheometer for a duration corresponding to the gastric digestion, and adjusting the reaction mixture for modeling intestinal digestion conditions for a duration corresponding to the intestinal digestion. The rheometer is equipped with a stirrer to homogenize the mixture and to measure the viscosity simultaneously. The food obtained from crushing has a size of 5-3000 mu m. The in vitro method comprises crushing the food to reproduce the mechanical degradation operated during mastication, mixing the crushed food to a solution modeling the gastric fluid in the reactor tank coupled to a rheometer for a duration corresponding to the gastric digestion, and adjusting the reaction mixture for modeling intestinal digestion conditions for a duration corresponding to the intestinal digestion. The rheometer is equipped with a stirrer to homogenize the mixture and to measure the viscosity simultaneously. The food obtained from crushing has a size of 5-3000 mu m. The solution modeling the gastric fluid comprises water maintained at an acid pH of 1-4 and a proteolytic enzyme such as pepsin. The enzyme is present in an amount of 0.025-2.5 wt.% in the gastric fluid solution. The mixture of crushed food and the solution modeling the gastric fluid undergo stirring in a thermostated reaction tank maintaining the medium at 37[deg] C and coupled to a viscosity measuring device. The modeling of intestinal digestion conditions is carried out by adjusting the pH in the reactor to a value of 6.3, adding 0.3 wt.% of bile salts and 0.4 wt.% of pancreatin and maintaining the stirring operation for a period of 90 minutes. The stirrer consists of 2-6 helical blades (1) driven by rotating around a vertical axis (2) corresponding to the tank of the reactor, and a support bar (3) perpendicular to the axis located at the lower end of the axis. The helical blades comprise a semi-thread and a thread or coil of helix. A coil is connected at the lower end of the blades by the support bar and at their upper ends by a second radial bar (4) parallel to the support bar. The reactor tank is coupled to a rheometer for 70 minutes, and is maintained at a temperature of 37[deg] C. The step of measuring the viscosity is replaced by oscillatory measures at low deformation allowing measuring the viscoelasticity when the consistency of the bowl becomes viscoelastic. The apparatus for measuring the viscoelasticity of the mixture obtains a sinusoidal deformation of 0.1% and a frequency of 1 HZ, and is equipped with an agitator. Independent claims are included for: (1) a rheometer equipped with an agitator; and (2) in vitro apparatus for modeling the consistency generated in vivo by a dry food during digestion.