Emission Spectrochemical Analysis of Food Material Using TEA CO₂ Laser-Induced Shock Wave Plasma

Abstract

A new method for spectrochemical analysis of food materials is presented using a Transverse Excited Atmospheric (TEA) CO 2 laser. Milk powders containing different amounts of Ca are mixed with KBr powder, and compressed to make pellets. The pellets are bombarded by the TEA CO 2 laser (300 mJ, 100 ns) under the surrounding gas of 300 Pa. The shape of the luminous plasma is hemispherical. This plasma is excited by the shock wave induced by the laser bombardment. It is proved that the relative intensity of the Ca 422.6-nm emission line to that of the K 404.4-nm emission line is proportional to the Ca content. This method has a bright prospect as a direct analytical method of food materials.