Quantitative analysis of sodium in self-raising flour by laser-induced breakdown spectroscopy

Abstract

The purpose of this study is to develop an alternative method to detect Sodium in selfraising flour by using laser-induced breakdown spectroscopy (LIBS). LIBS experiments were performed to examine the Na at 588.995 nm to quantify Na content in the sample. Eight self-raising flour sample pellets from two brands containing various concentrations of Na (NaCl-free, 1000ppm, 5000ppm, 10000ppm) were used to construct the calibration graphs. The constructed calibration curves were then used to indicate functions of Na concentrations, which shows good linearity from the sample “Pancake Mix” and “Lotus Flower Self-raising Flour”. The correlation coefficients (R2) values are 0.9431 and 0.9944 respectively, which show strong positive relationship between the intensity of signal and Na content in flour. Performed studies showed that LIBS is a simpler, faster and cheaper way to quantify Na concentration in commercial self-raising flour, compared to traditional quantitative chemical analysis, such as ICP-OES and AES.