Detection of Frozen–Thawed Duck Fatty Liver by MALDI-TOF Mass Spectrometry: A Chemometrics Study

• Main Authors: Laurent Aubry, Thierry Sayd, Claude Ferreira, Christophe Chambon, Annie Vénien, Sylvie Blinet, Marie Bourin, Angélique Travel, Maeva Halgrain, Véronique Santé-Lhoutellier, Laetitia Théron
• Format: Article
• Language: English
• Published: MDPI AG 2021-06-01
• Series: Molecules
• Subjects: frozen–thawing cycles; fatty liver; MALDI-TOF mass spectrometry; chemometrics; fraud detection
• Online Access: https://www.mdpi.com/1420-3049/26/12/3508

The marketing of poultry livers is only authorized as fresh, frozen, or deep-frozen. The higher consumer demand for these products for a short period of time may lead to the marketing of frozen–thawed poultry livers: this constitutes fraud. The aim of this study was to design a method for distinguishing frozen–thawed livers from fresh livers. For this, the spectral fingerprint of liver proteins was acquired using Matrix-Assisted Laser Dissociation Ionization-Time-Of-Flight mass spectrometry. The spectra were analyzed using the chemometrics approach. First, principal component analysis studied the expected variability of commercial conditions before and after freezing–thawing. Then, the discriminant power of spectral fingerprint of liver proteins was assessed using supervised model generation. The combined approach of mass spectrometry and chemometrics successfully described the evolution of protein profile during storage time, before and after freezing-thawing, and successfully discriminated the fresh and frozen–thawed livers. These results are promising in terms of fraud detection, providing an opportunity for implementation of a reference method for agencies to fight fraud.