IntroductionHuman digestion, a major concern due to the rapid development of nutrition-related chronic diseases,rely apart from enzymatic reactions on homogenization of the gastric content by antral contractions.Although recent CFD studies made it possible to explore the influence of the rheologicalproperties of the gastric content on the efficiency of gastric mixing, this key step is yet far from beingfully understood.ObjectiveThis work aims at discussing the influences of contraction frequency and viscosity of the digestain human gastric mixing by comparison with the mixing efficiency of an innovative soft elastic reactor(SER), that induces mixing by vibration of its wall in a similar way as antral contraction waves(ACWs) promote stomach motility.MethodologyIn this view, the SER mixing curve, recently established by Delaplace et al. (2018) using a dimensionalanalysis approach, was considered in order to determine the flow regime under which thegastric mixing of foods (viscosity ranging from 10-3 to 1 Pa.s) was performedMain findingsIt was shown that depending on the viscosity of the SER/stomach content and the amplitude of penetration/ACWs, the number of strikes/contractions required to achieve homogenization was largelydifferent. Moreover, the operating points of SER and ACWs mixing were close, justifying the comparisonbetween both reactors.ConclusionBased on this, the level of mechanical solicitation provided by human peristalsis was shown to benot as high as expected, and the mixing performance of distal region, confined in laminar regime,was found limited and not only due to mechanical solicitations. Further efforts are needed to investigatethe role of other physiological processes such as gastric secretions and gastric emptying inmixing performance of intragastric fluid homogenized by the antral contraction
