Cocoa smoky off-flavor: Chemical characterization and objective evaluation for quality control

•Application of a top-down approach to characterize cocoa smoky compounds.•HS-SPME-GC × GC-TOF MS to screen the volatile fingerprints of smoky and non-smoky cocoa.•Method translation and adaptation to HS-SPME-1D-GC-MS for quality control to lower sensitivity.•PCA and PLS-DA to select off-note marker...

Full description

Saved in:
Bibliographic Details
Published in:Food chemistry 2020-03, Vol.309, p.125561-125561, Article 125561
Main Authors: Perotti, Pamela, Cordero, Chiara, Bortolini, Cristian, Rubiolo, Patrizia, Bicchi, Carlo, Liberto, Erica
Format: Article
Language:English
Subjects:
Cacao - chemistry
Chemometrics
Chocolate - analysis
Cocoa volatilome
Gas Chromatography-Mass Spectrometry - methods
GC-MS
GC × GC-TOF MS
HS-SPME
Quality Control
Smoke
Smoky off-flavor
Volatile Organic Compounds - analysis
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:•Application of a top-down approach to characterize cocoa smoky compounds.•HS-SPME-GC × GC-TOF MS to screen the volatile fingerprints of smoky and non-smoky cocoa.•Method translation and adaptation to HS-SPME-1D-GC-MS for quality control to lower sensitivity.•PCA and PLS-DA to select off-note markers on 85 samples in cocoa beans and liquors.•Quantitation of ten markers selected to define the acceptation range. Cocoa smoky off-flavor is due to inappropriate post-harvest processing and cannot be removed in the subsequent chocolate-manufacturing steps. To date, no reliable analytical method to detect key-analytes responsible for smoky off-flavor in incoming raw material is available. This study aims to develop an analytical method, suitable for quality control, to detect smoky markers. The cocoa volatilome was first profiled by headspace solid phase microextration combined with comprehensive two-dimensional gas chromatography-mass spectrometry from a set of representative smoky and non-smoky samples; advanced fingerprinting revealed the chemicals responsible for the off-flavor. The results served to develop a 1D-GC method suitable for routine application. Ten identified smoky markers were subjected to accurate quantification, thereby defining operative ranges to accept/reject incoming bean samples. On average, these markers are present in smoky samples at 7 to 125 fold concentrations vs. those in non-smoky beans, ranging from 32.5 ng/g for naphtalene to 721.8 ng/g for phenol.
ISSN:0308-8146
1873-7072
DOI:10.1016/j.foodchem.2019.125561