Study On Dection Method Of Pork Freshness Based On Impedance Spectroscopy

Based on 3D printing technology,this study designs and constructs a system for simulating gastric digestion of human stomach to study the food(or food model)force and decomposition in the adult stomach.The system is based on the characteristics of gastric anatomy and physiological changes after intake of food.The main features of these bodies are transformed into a computer-controlled machine that simulates the dynamics of the stomach,the frequency,the gastric fluid secretion,and the peristaltic waves produced by the movement of the stomach in different situations.Compared to the human stomach,the physiological parameters of the artificial stomach show that the artificial stomach could simulate the digestion of food in the human stomach,which provide theoretical basis and technical support for the food industry and in vitro digestion studies.The main contents and results are as followings:The artificial gastric digestive system is constructed in full digitalization by using the water-soluble material and the 3D printing technique.The system consists mainly of the following structure: mechanical transmission system,electric compression system,gastric juice secretion and injection system,temperature control system and computer control system.Through continuous improvement and optimization of the key parameters of artificial stomach,such as gastric juice secretion rate,the role of the wall in the compressive force of the size,the system is closer to the real stomach of the dynamic gastric digestive process,including the mechanical transmission system for the movement of artificial stomach to provide power,electric compression device to simulate the stomach peristalsis,through a regular squeeze artificial stomach wall,both sides of the sensor measured the pressure range of 2.52 ± 0.15 N and 3.32 ± 0.16 N,with 3 times per minute peristaltic circulation.The secretion of gastric juice and food samples are controlled by a computer-controlled syringe pump and peristaltic pump according to a specific program,the temperature control system can make the whole model at 37 ℃ constant temperature under conditions.In order to explore the real force bearing magnitude of food in the process of gastric digestion and quantitatively reproduce the human stomach grinding force,we designed and customized a spherical aluminum mold with a diameter of 1.27 cm,using agar and guar gum as raw materials to make a gel pellet with a crushing force of 0.65 ± 0.15 N to simulate high and low viscosity food system in artificial stomach.We counted the number of intact pellets remaining in the stomach at each time point and obtained the relationship between the number of intact pellets remaining in the stomach and the digestion time,and analyzed the multivariate function variance for the repeated measurements.From the number of ruptured ball and the average rupture time,we can speculate that the actual force in the artificial stomach to confirm the human gastric grinding force can be simulated to artificial stomach.The experimental results show that the data measured in the artificial stomach are significantly correlated with the observed data in the human volunteers reported in the literature.The force of the artificial stomach through the extruded stomach wall is in the range of 0.2 N ~ 0.95 N.In this paper,rice is chosen as a model real food,and the digestive process of rice is observed in real time.The experiment mainly focuses on the real-time analysis of the disintegration and interaction between rice grains cooked in simulating human gastric motility.The main characteristics of the food components(including the typical grain size image after digestion,solid content,average particle size,etc.)and the physical properties of the gastric electrolyte solution(including kinematic viscosity,shear viscosity)are studied in the digestion process to provide the dynamic information of rice digestion in artificial stomachs and determine the superiority of artificial stomachs in the digestion process(especially solid food)compared with the existing in vitro digestive models.Results further confirm that artificial stomachs can simulate the shearing force of food in true human stomach during the digestion.In summary,this paper designs and constructs a systematic artificial stomach in vitro to simulate human stomach digestion system.Through the quantitative control of artificial stomach compression and compression frequency,programmed to control the secretion and temperature of gastric juice,basically reproduced the real stomach digestion in the process of dynamic conditions.Secondly,the gel pellet simulation digestion confirmed the grinding force of the human stomach model can simulate artificial stomach.Finally,the real food rice digestion quantitative analysis further supported the artificial stomach in the simulation positive action in gastric digestion.