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

Storage time of nut spreads using flash gas chromatography E-nose combined with multivariate data analysis

The quality assessment, in terms of lipid oxidative status, of food products stored in the long-term is of great importance, especially those with a high lipid content. Specifically, companies working in this sector need feasible, simple, and fast techniques that are suitable for quality or process control. Herein, a fingerprinting approach, based on headspace analysis carried out by flash gas chromatography electronic nose (FGC E-nose) and multivariate data analysis was applied to pistachio and gianduja spreads. These samples, differently packaged, were stored in climatic chambers at 40 °C for 180 days and their headspace fraction was analyzed periodically for a total of 15 sampling times. Principal component analysis showed a clear separation according to the packaging type for both pistachio and gianduja samples. Partial least squares regression models were developed to predict the storage time considering the aggregated data (R2 up to 0.985, RMSEP = 6.16 days) or separately (R2 up to 0.989, RMSEP = 5.71 days). Based on the obtained residual prediction deviation (RPD from 4.4 to 8.5 in prediction), the models can be considered suitable for use in quality control in an industrial environment

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

Characterization of virgin olive oils obtained from minor Tunisian varieties for their valorization

Several compositional parameters (fatty acids, tocopherols, polar phenols and volatiles) in virgin olive oils from varieties located at the center of Tunisia, namely Baldi, Chemchali, Neb Jmel, Tounsi and Besbessi from Gafsa and Chemchali and Sehli cultivated in Sidi Bouzid, were studied. To the best of our knowledge, this is the first study focusing on the chemical composition of virgin olive oils (VOO) from Sidi Bouzid. Significant differences were found between varieties from Sidi Bouzid and Gafsa in monounsaturated saturated fatty acid levels, some volatile compounds and γ-tocopherol amounts. Notably, Tounsi and Baldi VOOs showed the highest six carbon atoms alcohol contents, whereas Neb Jmel VOO revealed the highest aldehyde six carbon atoms content. Fatty acid composition, as well as tocopherol content, showed differences among different VOO. Principal component analysis and hierarchical component analysis on polar phenols, fatty acids, tocopherols and volatiles data evidenced a good discrimination among oils from the different investigated varieties

Research challenges and methods to study food preferences in school-aged children : A review of the last 15 years

Until only a few decades ago, there was little interest in research about children as consumers. Today, the food market for ''the small consumers'' is continuously growing and many foods and beverages are developed specifically for this target group. Furthermore, a better understanding of children's food preferences could help design strategies to reduce obesity and malnutrition. The present review examines the main research domains in which measurements of children's food preferences are applied. It also gives an overview of the progress made during the last 15. years in the field of consumer testing with children, highlighting the need of investigating and using new methods in addition to existing ones. Attention is devoted to the choice of specific methods according to the child's age.An intense interest in consumer and sensory research with children is demonstrated by the systematic increase of scientific publications on this topic. A shift in research methodology has been observed in the last 15. years, being research more focused on feeding behavior and healthy eating. Recent investigations confirm that children in the age range of 4-11. years are able to perform most traditional consumer tests in addition to more sophisticated methods (e.g. projective mapping, memory and emotion evaluation) if age-appropriate procedures are adopted

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

Sensory perception and food neophobia drive liking of functional plant-based food enriched with winemaking by-products

The use of phenol compounds obtained from unripe grapes as antioxidant sustainable food ingredients is challenging due to their specific sensory attributes, such as sourness and astringency. The aim was to evaluate sensory attributes perception and consumers' liking for beetroot purees added with phenols from unripe grapes. According to hedonic responses, consumer clusters were identified and characterized for eating behavioral attitudes. Three hundred two subjects (56% women, 18–60 years old) evaluated sweet, sour, astringency, and overall flavor intensity of and liking for four beetroot puree samples added with increasing phenols concentrations (0–1.93 g/kg). Results showed that liking decreased with increasing phenols. Interestingly, samples with highest phenols concentration, characterized by sourness, and astringency, were preferred by a segment of consumers (39% of the group). This group was characterized by a low food neophobia and tended to have high emotional eating scores compared to consumers preferring samples without or with the lowest amount of extract. These results suggest that the development of functional phenol-enriched products using winemaking by-products is challenging due to their sensory properties that negatively influence consumers' acceptance. However, with appropriate segmentation strategies it is possible to identify specific consumer targets who could appreciate these new functional foods. Practical Applications: Unripe grapes can be used as a sustainable phenol source for the development of new highly antioxidant foods. Indeed, an addition till 1.9 g/kg, besides improving both the nutritional content of the food matrices, as well as promoting the reuse of winemaking by-products, could be considered feasible from a sensory point of view. Specifically, new sustainable plant-based food product, characterized by specific sensory attributes, could be target for specific groups of consumers to foster the transition to the consumption of food products developed using value-added and sustainable ingredients

Simulating International Shipments of Vegetable Oils: Focus on Quality Changes

This investigation evaluated the quality changes of commercial vegetable oils after different simulated shipments. In particular, the oils were placed in containers with or without thermal insulation and subjected to two simulated shipments, from Italy to Los Angeles and to Quebec. The temperature profiles were monitored to simulate the real shipments conditions in laboratory through properly developed climate chambers. Different quality parameters were evaluated before and after the simulations, showing a high degree of oxidation for samples shipped to Los Angeles in standard containers. In this study, the thermal insulation container was effective in protecting samples from potential oxidative damage during simulated shipping.The authors would like to thank Enhancement of the Palestinian University System (E- PLUS) for PhD scholarship grants financed by the Italian Ministry of Foreign Affairs-Directorate General for Cooperation and Development (coordinated by the University of Pavia)

Investigación preliminar sobre los posibles efectos del tratamiento con arcilla mineral aplicado a aceites producidos a partir de aceitunas: enfoque sobre la eliminación de humedad y cambios en la composición

In this preliminary study, two non-filtered virgin olive oils (one freshly produced VOO-N; one VOO-O stored for one year) were subjected to moisture removal with mineral clay (raw or activated) and analyses were performed to attest possible effects on the quality of the product. The results demonstrated that the treatment of oil with mineral clay at 36-38 °C had no negative effect on the basic quality parameters or on the volatile comound profile. On the other hand, a significant decrease in the water amount as well as in pigments was observed in the samples subjected to this kind of treatment, in particular with raw clay. Regarding the colour measurement, the lightness (L) as well as the consumers’ acceptability exhibited a marked increase when oils were treated with raw clay.En este estudio preliminar, dos aceites de oliva vírgenes no filtrados (uno VOO-N recién producido y el otro, VOO-O almacenado durante un año) fueron sometidos a la eliminación del contenido de humedad con arcilla mineral (cruda o activada) y se realizaron análisis para atestiguar posibles efectos sobre la calidad del producto. Los resultados demostraron que el tratamiento del aceite con arcilla mineral, realizado a 36-38 °C, no tuvo consecuencias negativas en los parámetros básicos de calidad y en el perfil de los compuestos volátiles. Por otro lado, se observó una disminución significativa en la cantidad de agua y en los pigmentos en las muestras sometidas a este tipo de tratamiento, en particular con arcilla cruda. Con respecto a la medida del color, luminosidad (L) y aceptabilidad de los consumidores mostraron un aumento notable cuando los aceites se trataron con arcilla cruda

Potential of the Oxidized Form of the Oleuropein Aglycon to Monitor the Oil Quality Evolution of Commercial Extra-Virgin Olive Oils

The quality of commercially available extra-virgin olive oils (VOOs) of different chemical compositions was evaluated as a function of storage (12 months), simulating market storage conditions, to find reliable and early markers of the virgin olive oil (VOOs) quality status in the market. By applying a D-optimal design using the Most Descriptive Compound (MDC) algorithm, 20 virgin olive oils were selected. The initial concentrations of oleic acid, hydrophilic phenols, and a-tocopherol in the 20 VOOs ranged from 58.2 to 80.5%, 186.7 to 1003.2 mg/kg, and 170.7-300.6 mg/kg, respectively. K-270, increment K, (E, E)-2.4-decadienal and (E)-2-decenal, and the oxidative form of the oleuropein aglycon (3,4-DHPEA-EA-OX) reflected the VOO quality status well, with 3,4-DHPEA-EA-OX being the most relevant and quick index for simple monitoring of the "extra-virgin" commercial shelf-life category. Its HPLC-DAD evaluation is easy because of the different wavelength absorbances of the oxidized and non-oxidized form (3,4-DHPEA-EA), respectively, at 347 and 278 nm