Matrix-matching calibration as a new approach for quantitation of monosodium glutamate in food seasoning powders using high performance thin layer chromatography

Monosodium glutamate (MSG), the sodium salt of the L – glutamic acid, is a flavor enhancer compound, which naturally exists in different foodstuffs being responsible for the “umami” taste. It is also used as a food additive (E612) in various commercial products, although its consumption in high quantities having potential toxic effects. A new HPTLC method was developed in order to determine MSG in commercial food seasoning powders (FSPs). The analysis was carried out on HPTLC silica gel 60 F 254 plates using a mixture of propanol – acetic acid – water 6:2:1 (v/v/v) as mobile phase. The detection was done in visible light after derivatization with ninhydrin and the images of the plates were processed by a digital processor. Two type of calibration curve were used, namely, standard calibration curve for quantification of MSG in vegetables and matrix-matched calibration curve for determination of MSG in FSPs. Also, the evaluation of linear, quadratic and non-linear equations to be used for each type of calibration was performed. The results proved that the quadratic equation fits the results best in both cases. The obtained results prove the MSG addition in different FSPs, which can be used in the routine analysis of this food additive. • Monosodium glutamate is analyzed in vegetables and food seasoning products by HPTLC. • Among the linear and non-linear equations, the quadratic one fits the data best. • Matrix-matched calibration is more effective for determining monosodium glutamate. • Monosodium glutamate natively exists in vegetables used for food seasoning product.