An HS-GC-IMS Method for the Quality Classification of Virgin Olive Oils as Screening Support for the Panel Test

© 2020 by the authors.Sensory evaluation, carried out by panel tests, is essential for quality classification of virgin olive oils (VOOs), but is time consuming and costly when many samples need to be assessed; sensory evaluation could be assisted by the application of screening methods. Rapid instrumental methods based on the analysis of volatile molecules might be considered interesting to assist the panel test through fast pre-classification of samples with a known level of probability, thus increasing the efficiency of quality control. With this objective, a headspace gas chromatography-ion mobility spectrometer (HS-GC-IMS) was used to analyze 198 commercial VOOs (extra virgin, virgin and lampante) by a semi-targeted approach. Different partial least squares-discriminant analysis (PLS-DA) chemometric models were then built by data matrices composed of 15 volatile compounds, which were previously selected as markers: a first approach was proposed to classify samples according to their quality grade and a second based on the presence of sensory defects. The performance (intra-day and inter-day repeatability, linearity) of the method was evaluated. The average percentages of correctly classified samples obtained from the two models were satisfactory, namely 77% (prediction of the quality grades) and 64% (prediction of the presence of three defects) in external validation, thus demonstrating that this easy-to-use screening instrumental approach is promising to support the work carried out by panel tests.This work is supported by the Horizon 2020 European Research project OLEUM “Advanced solutions for assuring the authenticity and quality of olive oil at a global scale”, which received funding from the European Commission within the Horizon 2020 Programme (2014–2020), grant agreement no. 635690. The information expressed in this article reflects the authors’ views; the European Commission is not liable for the information contained herein. The study is also supported by Associazione Italiana Industria Olearia (ASSITOL, Italy) that awarded a post-graduate training grant.Peer reviewe

Developing a new method to analyse volatile substances in extra virgin olive oil

The applications of gas chromatography in the field of food science are of great importance for the assessment of food quality and safety. As an example, volatile compounds are key molecules in the definition of the overall quality of extra virgin olive oil.1 New methods to analyse volatile substances in olive oil by solid-phase microextraction and gas chromatography coupled to mass spectrometry are currently under investigation in our laboratory. Interesting preliminary results show that the aqueous extract of olive oil can provide the same result as when the analysis is carried out on the oil as such, with the advantage that the oil aqueous extract is much easier to handle, the solid-phase microextraction fiber assembly used has a much longer lifetime and the use of an internal standard is allowed, while using the oil as such, the homogenization of the internal standard is practically unfeasible. The results of the study will be presented and discussed. References: 1) Angerosa, F.; Servili, M.; Selvaggini, R.; Taticchi, A.; Esposto, S., Montedoro, G. Journal of Chromatography A 2004, 1054, 17-31

OLEUM Project. Classification of virgin olive oils based on quality grades and presence of defects using HS-GC-IMS as a rapid screening tool.

This data set contains the underlying data of the scientific publication: Valli, E.; Panni, F.; Casadei, E.; Barbieri, S.; Cevoli, C.; Bendini, A.; García-González, D.L.; Gallina Toschi, T. An HS-GC-IMS Method for the Quality Classification of Virgin Olive Oils as Screening Support for the Panel Test. Foods 2020, 9(5), 657; https://doi.org/10.3390/foods9050657. Sensory analysis, carried out by Panel test, is essential for the quality classification of virgin olive oils (VOOs). The presence and perceived intensity of fruity attribute and sensory defects are linked with the occurrence of specific volatile compounds. Instrumental screening methods based on analysis of volatiles can support the Panel test through fast pre-classification of samples with a known probability, thus increasing the efficiency of quality control. A Headspace Gas Chromatography Ion Mobility Spectrometer (HS-GC-IMS) was used to analyze commercial VOOs by a semi-targeted approach. PLS-DA models were built by data matrices composed of 15 selected volatile compounds with which was possible to classify the samples based on quality grades and presence of defects

GC-IMS screening to cluster the sensory grades of virgin olive oils

In this work, the use of a gas chromatography coupled to an ion mobility spectrometer with a tritium source was investigated for the discrimination of virgin olive oils previously sensory assessed (EU Reg. 1227/2016) and characterized by different quality grades (extra virgin, virgin, lampante). The samples were injected by a headspace system and, after the gas chromatographic separation, the ion mobility data coming from the eluted volatiles were processed with various chemometric tools. The preliminary elaboration evidenced a promising capacity to discriminate the samples according to their quality grade. The proposed approach is also sustainable and fast. This work was developed in the context of the project OLEUM “Advanced solutions for assuring authenticity and quality of olive oil at global scale“ funded by the European Commission within the Horizon 2020 Programme (2014–2020, grant agreement no. 635690). The information expressed in this abstract reflects the authors’ views; the EC is not liable for the information contained therein. The authors are grateful to the six sensory panels of the OLEUM consortium for the sensory evaluation of samples

Transcortical endoportal subchoroidal endoscope-assisted approach to the third ventricle: from virtual reality to anatomical laboratory

Surgical approaches to the third ventricle (TV) have always represented a technical challenge in neurosurgery. Virtual reality (VR) is attaining increasing relevance in training programs and preoperative planning. The aim of this study is to demonstrate the worthwhile mutual contribution of VR simulations and specimen dissections to develop a new surgical approach to the TV

HS-GC-IMS: A Screening Method Discriminating Quality Grades in Virgin Olive Oils by Specific Volatile Compounds

This work is developed in the context of the project OLEUM “Advanced solutions for assuring authenticity and quality of olive oil at global scale”, funded by the European Commission within the Horizon 2020 Programme (GA no. 635690)Peer reviewe

OLEUM Project. Olive oil fraud and possible countermeasures. Emerging trends

A review of most common types of fraud in the olive oil (OO) sector highlights that most common infringements are the marketing of virgin olive oil (VOO) as extra virgin olive oil (EVOO), and blends of other vegetable oils with OO being marketing as OO. This dataset contains the aggregated results of an international on-line survey of EU and non-EU stakeholders in the olive oil sector. The aim of the on-line survey was to highlight he priorities in addressing efforts to fight OOs fraudulent cases