Mid-Infrared Spectroscopy for Juice Authentication – Improvement of Modeling Power for Juice Differentiation by Analyzing Signature-like Phenolic Spectra
Advisor:Giusti, M. Monica
MetadataShow full item record
Series/Report no.:Food Science and Technology. Graduate student poster competition, 2007
Determination of food authenticity is an important issue in food safety and quality control. Mid-infrared spectroscopy provides rapid chemical profiling of agricultural products and could become an effective tool for authentication when coupled to chemometrics. This study developed a simple protocol for classifying commercial juices using attenuated total reflectance infrared spectroscopy, and sought for improvement of modeling power by analyzing the taxonomic compounds in the phenol-rich fraction. Spectra from 52 juices together with their extracted sugar-rich and phenol-rich fractions were obtained to construct multivariate models (HCA and SIMCA) for pattern recognition analysis and prediction. Spectra of the sugar-rich fraction, comprising primarily of sugars and simple acids, almost superimposed the whole juice spectra. Solid phase extraction enriched phenol compounds and provided signature-like spectral information that substantially improved the SIMCA modeling power over the whole juice or sugar-rich fraction models. Zero-percent misclassification was achieved by the phenol-rich fraction model at commodity and manufacturer level, where as the whole juice model was only feasible for commodity level differentiation. HCA successfully recognized the natural grouping of juices based on ingredients similarity and revealed that the phenol fraction contained sufficient information to differentiate among the same type of juice from different manufacturers. The infrared technique assisted by phenol fractionation and chemometrics provided a promising analytical method for the assurance of juice quality and authenticity.
Items in Knowledge Bank are protected by copyright, with all rights reserved, unless otherwise indicated.