Characterization Of Must And Wine Of Six Varieties Of Grapes By Direct Infusion Electrospray Ionization Mass Spectrometry.

Samples of must derived from six different varieties of grapes taken during the fermentation process, as well as the respective wine samples directly after the end of the malolactic fermentation, were analyzed by direct infusion negative ion mode electrospray ionization mass spectrometry (ESI-MS). Diagnostic ions for must were different from those of wine samples, although small variations for each of the grape varieties were also detected. The addition of unfermented must or sugar to wine could also be clearly detected. The spectra were acquired in a few minutes per sample, indicating that ESI-MS can be used for high-throughput analysis of samples and should prove useful for quality control during and after the fermentation process.41185-9

Aflatoxin Screening By Maldi-tof Mass Spectrometry.

Efficient detection of aflatoxins B1, B2, G1, and G2 has been performed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry using a UV-absorbing ionic liquid matrix to obtain matrix-free mass spectra and addition of NaCl to enhance sensitivity via Na+ cationization. Using ionic alpha-cyano-4-hydroxycinnamic acid (Et3N-alpha-CHCA) as the matrix, matrix-free mass spectra in the m/z range of interest are acquired, and the B1, B2, G1, and G2 aflatoxins are readily detected with an LOD as low as 50 fmol. The technique is fast, requires little sample preparation and no derivatization or chromatographic separation, and seems therefore to be suitable for high-throughput aflatoxin screening. It should be easily extended to other micotoxins and provide an attractive technique to control the quality of major crops subjected to huge world commercial trades such as peanuts, corn, and rice as well as to monitor bioterrorism threats by micotoxin poisoning.778155-