Real-time detection of authenticity and adulteration of krill phospholipids with soybean phospholipids using rapid evaporative ionization mass spectrometry: Application on commercial samples

Abstract: The functional food ingredient of krill phospholipids are easily adulterated with soybean phospholipids due to their similar appearance and physical behavior. In this study, a novel in-situ method was developed for real-time detection of authenticity and adulteration of krill phospholipids with soybean phospholipids using an electric heating probe based rapid evaporative ionization mass spectrometry (REIMS). The commercial samples could be directly analyzed without preparation. The REIMS conditions were optimized such that the cauterizing duration was 3 s, the temperature of the heating probe was 450 °C and the flow rate of auxiliary solvent was 100 μL min−1. The compositions of krill and soybean phospholipids were analyzed by mass spectrometry, and the obtained data was used to establish the multivariate statistical models. The results indicated that the krill phospholipids could be successfully distinguished from soybean phospholipids with accuracy ≥96.58% on the basis of the characteristic ions of m/z 279.23, 301.22, 629.45, 807.43, 831.43 and 833.44. The effectiveness of these marker ions was proved by blind sample tests. This method provides a reference for evaluating the adulteration of krill phospholipids in the market and expands the application field of REIMS technology.