Research Of The Food Freshness Test Methods Based On Malodorous Gas Analysis

In recent years,the issue of food safety has been exposed by more and more news media.Freshness rather than having ample food is the current public’s pursuit of food.As a deciding factor to test pork quality,freshness of pork can directly influence the public’s food safety and health.Currently,there are multiple ways to test freshness of pork.However,due to complex operations,expensiveness of test equipment,long test period and damage done to samples,an efficient,accurate and zero-damage test method featuring easy operations should be found out to test pork freshness.Such a test method is of vital research significance and practical significance.First,research progress in terms of pork,vegetable and fruit freshness test both at home and abroad is summarized.Focus is on introducing principles and methods related to pork freshness test.Then,based on the sensor array principle,a system made up of different types of sensors and capable of testing malodorous gas volatized during the pork rotting process is developed.By analyzing the volatile substances of various groups during the pork rotting process,this paper finally works out a test system made up of the sensor array targeting at testing H2 S,NH3 and ethyl alcohol.The volatile gas test system consists of four parts,namely the gas cell,the sensor array,the lower computer and the upper computer.The lower computer has C8051F020 at its core,responsible for gas collection,sequential control of the test system,collection and processing of sensor signals and data communication with the upper computer.The upper computer includes data collection and analysis based on LabVIEW,and the freshness judgment interface based on MATLAB.This paper conducts a detailed exposition of the hardware development of the lower computer,the programming of the upper computer,etc.The experiment part of this paper measures the TVB-N base from the rotting pork and the voltage value of the malodorous gases during the rotting process in the environment of 30 and 85% of humidity.At last,the stability and repeatability of the sensor test system is ℃tested;the influence of flow on results of the sensor test system and the response relationship of every single substance to every sensor are analyzed.In the end,it is found that the accuracy of the test system can reach as high as 95% through multiple experimental groups.It suggests that the test method based on analysis of pork’s volatile gas can meet the fresh judgment requirements of accuracy,efficiency and none damage.At the end of this paper,limits of this experiment and improvement measures are pointed out,and the author also predicts the future research direction and achievements in the field.