Uncertainty evaluation for determination of ethanol content in wine by two methods
Pycnometermethod and Near-infrared spectroscopy were used to determine the ethanol content in wine,two uncer-tainty evaluation methods for different analysis processes are established,to evaluate the dispersion of test results,identify various influencing factors.The results show that the uncertainty component is more introduced in the pycnometer method,a-mong them,the uncertainty generated by density bottle calibration is the largest;the uncertainty component introduced by Near-infrared spectroscopy is less.The expanded uncertainty is:Pycnometer method x=12.12%vol,U(x)=0.10%vol,k=2;Near-infrared spectroscopy x=12.11%vol,U(x)=0.079%vol,k=2.