Application of a non-targeted approach by Flash Gas Chromatography-E-nose to discriminate the geographical origin of virgin olive oils

One of the fraudulent practices often applied in the olive oil sector concerns the mislabelling of the geographical origin of the products. In order to ensure that consumers are not mislead, the European Union issued a regulation concerning the definition of specific rules for the indication of geographical origin in the label (EU Reg. 29/2012). Beyond the compulsory traceability, the application of specific analytical techniques could be a useful tool to verify the conformity between the product and the information reported on the label. The aim of this work was to evaluate the effectiveness of a Flash Gas Chromatography-E-Nose, an instrument that combines functionality of electronic nose and ultra-fast GC, for the evaluation of the geographical origin of virgin olive oils (VOOs). For this purpose, more than 150 VOOs, different for their geographical origin (from single EU countries, such as Spain, Italy and Greece, and from single extra-EU countries, such as Tunisia, Turkey and Morocco) were collected and analyzed. Subsequently, a chemometric elaboration applied, with a non-targeted approach, to the chromatographic traces was realized. This permitted to build a model able to satisfactorily discriminate samples according to their geographical origin. This work is developed in the context of the project OLEUM \u201cAdvanced solutions for assuring authenticity and quality of olive oil at global scale\u201d, funded by the European Commission within the Horizon 2020 Programme (2014\u20132020, GA no. 635690). The information expressed in this abstract reflects the authors\u2019 views; the EC is not liable for the information contained therein

Children preferences of coloured fresh cheese prepared during an educational laboratory

Choices among young consumers are mainly driven by food preferences; in particular, a connection between appearance and acceptance of food has been highlighted, together with a general lack of knowledge of food processing. For these reasons, educational activities are important to increase scientific knowledge and awareness. The cheese-making educational laboratory described herein involved children, adolescents, and their parents/teachers in the preparation of fresh and naturally-coloured cheeses. At the end of the activity, both the colour preference and possible relation between preference and colour of cheese prepared were investigated administering a short questionnaire

Design and in-house validation of a portable system for the determination of free acidity in virgin olive oil

Nutritional and healthy values are well known properties of virgin olive oil (VOO). The product quality, in terms of belonging to a specific quality grade (extra virgin, virgin, lampante), is defined by a set of chemical-physical and sensory measurements. According to the official regulation of the European Union (EU Reg. 1348/2013)the free acidity is the first parameter that has to be determined by analysts; it gives information about the quality of the olives used to produce the VOO as well as the hydrolytic state of VOO just produced and stored. The official procedure is based on an acid-base titration that needs to be carried out in a chemical laboratory. In this paper a portable battery-operated electronic system to measure olive oil free acidity is presented: the system can be used for quick \u201cin situ\u201d tests in a production environment (olive oil mills or packaging centers)by people without particular training. The working principle of the system is based on the creation of an emulsion between oil and a hydroalcoholic solution: the free acidity is estimated on the value of the emulsion electrical conductance. The proposed system has been calibrated and in-house validated showing good results in terms of limit of detection and quantification, precision and accuracy. Moreover, a good correlation (R 2adj = 0.97)with free acidity data obtained applying the official method on 30 olive oil samples belonging to different commercial categories (extra virgin, virgin and lampante olive oil)has been evidenced

Destino de agroquímicos aplicados nos cultivos na região do aquífero karst em Colombo, PR.

Resumo

Determination of fatty acids ethyl esters in virgin olive oils: proposals to enhance the EU official method

Fatty acids ethyl esters (FAEEs) are markers for virgin olive oils obtained from olives of poor quality or not adequately stored before being processed. FAEEs can also be considered as indirect markers in detecting the illegal treatment of soft deodorization that can be applied to slightly defective olive oils, as they are difficult to be removed from the oils at the conditions reached during this technological process. The official FAEEs determination (EU Reg. 61/2011) suffers some drawbacks in terms of amount of solvents and long time of analysis, linked with the preparative procedure to isolate these compounds. The aim of this work is to study the application of an HPLC-UV as a rapid alternative approach to the traditional liquid chromatography applied in the preparative phase. After the set up of the most appropriate working conditions (eg. mobile phase, flow, injection volume), some validation parameters (eg. precision, accuracy, LOD and LOQ, recovery) have been evaluated, in order to check the effectiveness of the proposed method. Moreover, considering the GC-FID step, the use of a PTV (programmed temperature vaporizer) injector as an alternative of the on-column one was evaluated. This work is developed in the context of the project OLEUM \u201cAdvanced solutions for assuring authenticity and quality of olive oil at global scale\u201c, funded by the European Commission within the Horizon 2020 Programme (2014\u20132020, GA no. 635690). The information expressed in this abstract reflects the authors\u2019 views; the EC is not liable for the information contained therein

Data for: Design and in-house validation of a portable system for the determination of free acidity in virgin olive oil

Data set linked to a scientific paper about the development and in-house validation of a portable system for the determination of the olive oil free acidity.THIS DATASET IS ARCHIVED AT DANS/EASY, BUT NOT ACCESSIBLE HERE. TO VIEW A LIST OF FILES AND ACCESS THE FILES IN THIS DATASET CLICK ON THE DOI-LINK ABOV

Italian and Spanish commercial tomato sauces for pasta dressing: study of sensory and head-space profiles by Flash Profiling and SPME-GC-MS

This work aimed to the study the sensory characteristics and the head-space profile of 18 commercial tomato sauces for pasta dressing: 9 samples purchased from Italy and 9 from the Spanish market. The characterization of volatile molecules was performed by SPME-GC-MS, whereas the sensory attributes of each sample were evaluated by Flash Profiling method: this last rapid approach permitted to value characteristics perceived by smell and taste and to rank the samples according to the selected descriptors. Sensory and instrumental data were statistically elaborated by GPA in order to value the consensus degree among assessors about the ranking position of samples, whereas the most frequent sensory attributes and categories of volatiles were used as input data for the MFA. In the head-space of the samples, 100 compounds were tentatively identified, but only those responsible for specific olfactory attributes were considered (e. g. basil, fresh or cooked tomato, etc.). Each set of samples was mainly characterized by specifics sensory notes. Some significant positive correlations between volatile molecules known as related with specific sensory attributes and the sensory results (ranking) were found. The aroma profiling showed some main differences: Spanish samples were characterized by the highest content of compounds linked with the thermal treatments of tomatoes and with the presence of raw and saut\ue9ed garlic and onion, whereas, the Italian, by basil typical terpenes and by markers of fresh tomato. On the sensory side, assessors perceived more frequently the presence of garlic, onion and sweet pepper in Spanish samples whereas basil/aromatic herbs and acid taste were dominant in Italian ones. The results confirmed the strict relation between the formulation/processing and the aromatic profile of the sauces, thus evidencing an interesting agreement between the sensory and the instrumental data that could be relevant both for consumer testing and the research and development

Italian cold-pressed hazelnut oils: conjoint analysis of sensory quality vs volatile profile

Cold-pressed oils, produced only by mechanical extraction, can be considered high quality products, almost comparable to virgin olive oils. Among these, cold-pressed hazelnut oil is highly appreciated by many consumers. This unrefined oil retains some volatile compounds, characteristic of the primary vegetable material (raw or toasted hazelnuts) and responsible of peculiar sensory notes that can be olfactory perceived (directly or indirectly). The aim of this study was to investigate the possible correlation existing between volatile profile and sensory notes in 10 samples of cold-pressed hazelnut oils, purchased directly from the Italian market. The sensory profile of the samples was defined by quantitative descriptive analysis (QDA®) and their evaluation was conducted by a panel of fully trained judges; the training of the panel was monitored and evaluated through the use of PanelCheck software. The volatile composition was determined by SPME-GC-MS, in order to identify all the volatile compounds responsible for positive (e.g. raw or toasted hazelnuts) or negative (e.g. burnt) sensory notes. Finally, all the chemical and sensory values were elaborated and interesting correlations among analytical data were obtained. In particular, peculiar sensory notes, as well as specific volatile molecules useful as possible markers of the cold pressed hazelnut oil quality of were evidenced. The research was carried out with the financial contribution of the Italian Ministry of Instruction, University and Research in the framework of the PRIN 2009 project ‘‘Innovative technologic applications to improve the extraction yield of virgin oils from olives and seeds and for rapid controls of their quality’’

Sensory and instrumental study of Taralli, a typical Italian bakery product

Taralli is a bakery snack food, typical of the south of Italy, that has currently become very popular worldwide as a savory snack or bread substitute. However, few studies have focused on its physical and sensory characteristics. The present work aims to select sensory and instrumental information that is able to characterize Taralli with similar formulation and size. For sensory characterization purposes, conventional profiling was applied on samples from different producers. All samples were also subjected to physical analysis of appearance and textural proprieties. Three samples of the set, differing only in storage time, were evaluated to assess changes in sensory characteristics during this period and a discrimination test (triangle test) was also applied for this purpose. The test results confirmed that the sensory analysis allowed a description of the entire range of characteristics resulting from stimulation of senses by physicochemical properties of the food. This methodology was effective in evaluating the quality characteristics and identify differences between Taralli samples during different storage times. Instrumental tests were also applied to assess food quality. The results revealed that a combined approach allowed obtaining more information about the product characteristics and definition of quality standards. This study also suggests the use of physical parameters obtained by simple and rapid instrumental tools can support sensory analysis, especially for evaluations that are fatiguing, when decisions made with the sensory data are critical or to provide objective reference standards that are suitable for training purposes

Bitterness and pungency perceived in extra virgin olive oil and in other foods: is there any relation?

The aim of this study was to investigate the bitterness and the pungency as positive attributes of extra virgin olive oils (EVOOs) by correlating their intensities with the same attributes perceived in aqueous solution and in other foods: chocolate cream (for bitterness) and tomato sauce (for pungency). For this purpose, the bitterness and the pungency of one EVOO, characterized by medium intensities of both attributes (IOC Panel test), were assessed by a group of male and female consumers (20-60 years old) using general Labeled Magnitude Scales (gLMS). The same subjects were also asked to evaluate the bitterness of four chocolate creams - at different concentrations of sugar - and the pungency of four tomato sauces - at different concentrations of capsaicin. The consumers assessed, by the gLMS, also three aqueous solutions: one of caffeine, one of capsaicin and a single solution of PROP (n-propyilthiouracyl). Based on the PROP perceived intensity, subjects were classified in three different classes, namely PROP super tasters, medium tasters, and nontasters. The density of fungiform papillae (FP) of each taster was also determined and the subjects were accordingly divided in high FP and low FP individuals. The statistical elaboration of all the results (Pearson’s correlations) permitted to establish that some relations exist among the bitterness and pungency perceived respectively in EVOO, in aqueous solutions and in other foods and to hypothesize possible relations with the classification of subjects, in respect with their PROP status and FP density. Moreover, all the significant differences among the average sensory results, calculated for each of the three PROP groups (by Fisher’s LSD or Kruskal-Wallis test) and for each of the two FP categories (by Student t-test or Mann Whitney test), were discussed: the objective was to highlight any eventual effects of FP number and/or PROP status on the perceived bitterness and pungency, within the different PROP and FP groups. This investigation represents a first approach for verifying also if the above mentioned sensory attributes, namely the perceptions linked with the molecules involved (polyphenols, capsaicin, caffeine, n-propyilthiouracyl), are somehow affected by the lipidic or aqueous nature of the foods