Rapid Qualitative and Quantitative Analysis of Edible Oils by MALDI-MS Technology

Qualitative and quantitative analysis of edible oils have been important issues in food safety. A direct analysis of edible oils using matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) have been developed and a database containing spectra of more than 30 different types of pure edible oils have been established. Since different types of pure edible oils have different MALDI-MS spectral patterns, the authenticity of an edible oil sample can be determined by comparing its MALDI-MS spectrum with those of its labeled oil in the established database with a high correct classification rate. The MALDI-MS spectral patterns of blended edible oils are related to its compositional edible oils, hence the proportions of edible oils in blended edible oils can be measured with good accuracy by using chemometric methods to establish quantitative models based on the MALDI-MS spectra. 

Compared to conventional techniques for analysis of edible oils, using MALDI-MS is much faster which allows direct analysis of edible oils, without the need of sample extraction, derivatization, sample cleanup and separation. It takes only several minutes for the technique to analyze one edible oil sample which can greatly reduce cost. The technique can be used by the industry to authenticate edible oils and screen out mixed edible oils and recycled edible oils.