Does Authenticity of Virgin Olive Oil Sensory Quality Require Input from Chemistry?

Abstract

The methodology of sensory assessment (“panel test”) of virgin olive oil (VOO) is the sensory method included in international regulations and its application is compulsory in trading. Despite its application has been a success in authenticity of VOO quality, the application of panel test is not exempt of heated debates and controversies among olive oil actors that sometimes surpasses scientific arguments. Problems are consequence of some disagreements in the evaluation of the same VOOs from different testing laboratories, and today, there is a clamor for its enhancement from a considerable part of the industrial sector. The thin line that exists between the absence of sensory defects in extra‐VOOs and a very slight sensory defect that may be perceived in some VOOs by some tasters is in the origin of the controversy. Thus, this work is focuses on providing practical solutions to the current concerns of Panel Test after analyzing proposals evaluating aroma descriptors from chemistry, examining flaws of panel test and strengthening its weak points. Practical Applications: The work describes a strategy that combines volatiles and sensory descriptors for avoiding disagreements with results provided by non‐recognized testing laboratories, and proposes a blueprint for improving the process of training tasters with reference materials.

Formulations of Rancid and Winey-Vinegary Artificial Olfactory Reference Materials (AORMs) for Virgin Olive Oil Sensory Evaluation

“…Some difficulties persist, however, in perceiving and distinguishing a specific defect in VOOs when the defect intensity is very slight (e.g., close to 0.0 median). A debated classification can also occur in the case of oils that have an intensity of the defect close to the limit between VOO and LOO [ 15 , 16 , 17 ].…”

“…Additionally, the difficulty in recognizing a sensory defect at low intensity with respect to other sensory characteristics in the oil is also given and may add more uncertainty to the evaluation. This is particularly true in the case of oils that have more than one defect and for which the classification depends on the agreement reached by the tasters not only on the intensity, but also on the type of the defect perceived [ 15 ].…”

“…In this regard, in a recent work [ 16 ] on the alignment and the proficiency of VOOs sensory panels, the authors proposed several tools for quality control (i.e., a new decision tree scheme and formative reassessments) that allow a reliable classification of samples and highlighted the need for new reliable reference materials to enhance the skills of the panel in recognizing, identifying, and quantifying sensory attributes, a statement with which other authors have agreed [ 15 ]. Currently, in order to control these aspects, to train panelists and to harmonize odor thresholds, reference oils are regularly provided by the IOC or are obtained by the panel leader and are considered as RM.…”

Supporting the Sensory Panel to Grade Virgin Olive Oils: An In-House-Validated Screening Tool by Volatile Fingerprinting and Chemometrics

“…This evaluation is important to get a global picture of the sensory properties of virgin olive oil and it is particularly precious and hardly replaceable when describing the sensory profile of EVOO under quality schemes, such as Protected Designation of Origin [ 4 ]. Although the panel test has been responsible for improving the quality of virgin olive oils in the last years [ 5 ], many authors agree on the controversies about this method [ 4 , 5 , 6 ]. As a matter of fact, since it was first introduced into European Regulations in 1991, it has undergone many revisions as the result of a continuous study of its performance [ 7 ].…”

“…Even so, the sensory panel test still presents some drawbacks linked to the method’s nature, such as the limited number of samples assessed per day and misalignment between panels, among others [ 5 ]. It is also important to remember that the global production of virgin olive oil is growing at worldwide scale, while the number of recognized sensory panels is limited [ 6 ]. For all these reasons, setting up an instrumental screening tool that supports the sensory panel has become a need that should be fulfilled.…”