Traditional olive oil processing includes batch olive paste kneading for 30-60 min. Microwave (MW) treatment of the olive paste have recently shown to continuously provide faster conditioning, while megasound (MS) treatment have been shown to enhance oil extractability. In the present work the virgin olive oil standard parameters, sensory descriptors, and phenolic and headspace composition upon treatment of oils obtained using novel process enhancement interventions, and their combination in an industrial plant is examined. Standard parameters are within the international specifications. The Control and MW process provide similar phenolic composition but a post MS intervention significantly increased total phenolic content, and decrease total C5 and C6 aldehydes in the MW treated paste. These results encourage further developments for a combined continuous MW and megasonic conditioning technology to fasten the olive oil extraction, to enhance yields, and total phenolic content. Practical Applications: Microwave and megasounds are two technologies easily implementable on industrial olive oil extraction plant. They permit to simplify the entire plant and could replace totally the malaxers section. This new technology allows having a uniform paste treatment in continuous mode, enhancing the olive oil quality.

The results of this study suggest that Andean corn flours are a suitable and acceptable product for celiac consumers and can be used in the production of spaghetti for celiac consumers but should be reformulated for non-celiac consumers.

SUMMARY:Five virgin olive oil samples were evaluated by 122 consumers for their color acceptability and expected quality on 9-point structured scales. A description of the attributes expected in the different oils was obtained from the responding consumers by means of a check-all-that-apply questionnaire consisting of a list of 17 possible virgin olive oil attributes. Hierarchical cluster analysis led to the identification of two consumer clusters with distinct behavior. Whereas one consumer cluster attributed higher quality to those oils that were greener in color, which they described as tasty, rich-flavored, strong-tasting, herb-flavored and expensive, consumers in the other cluster assumed that greener olive oils were of a poorer quality, as they described them as strange-tasting, strong-tasting, herb-tasting and defective. Despite the contrasting perception of a virgin olive oil's green color, the respondents, irrespective of cluster, presumed that the virgin olive oil that was the yellowest in color was of poor quality and cheap, also assuming that it had a milder taste than the other oils. KEYWORDS:Color; Consumer; Olive oil; Sensory evaluation RESUMEN: Influencia del color en la calidad del aceite de oliva virgen percibida por consumidores de un país con olivicultura emergente. 122 consumidores evaluaron el color de 5 muestras de aceite de oliva virgen, midiendo su aceptabilidad y la calidad esperada por medio de una escala estructurada de 9 puntos y describiéndolas por medio de preguntas "marque todo lo que corresponde" que consiste en una lista de 17 términos posibles para atributos de aceites de oliva extra vírgenes. Mediante un análisis de conglomerados jerárquico se identificó a dos grupos de consumidores Los consumidores de ambos grupos consideraron que los aceites más amarillos eran de baja calidad, describiéndolos como baratos y de gusto suave. Un grupo de consumidores asignó puntuaciones de calidad alta a todos los aceites con colores verdes, describiéndolos como sabrosos, aromáticos, con gusto fuerte, con sabor a hierba y caros. El otro grupo de consumidores consideró que los aceites de color verde más intenso eran también de baja calidad, describiéndolos como con sabor extraño, con gusto fuerte, con sabor a hierba y defectuosos. Este estudio demuestra que en los países con olivicultura emergente pero con poca tradición de consumo de aceite de oliva, los consumidores aún no tienen preferencias comerciales claras sobre el color de este producto, aunque coinciden en rechazar y considerar como de baja calidad a los aceites de oliva amarillos posiblemente por asociarlos con los aceites de semillas que habitualmente se encuentran en el mercado. PALABRAS CLAVE: Aceite de oliva; Color; Consumidores; Evaluación sensorialCitation/Cómo citar este artículo: Gámbaro A, Raggio L, Ellis AC, Amarillo M. Virgin olive oil color and perceived quality among consumers in emerging olive-growing countries. Grasas Aceites 65 (2): e023. doi: http://dx.doi.

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Two monovarietal extra virgin olive oils (Arbequina and Coratina), produced in Uruguay, were studied over a period of 12 months storage in amber bottles at 30 º C. Peroxide index, K 232 , K 270 , ∆K, OSI induction time did not exceed the maximum limits set by the International Olive Council (IOC) during the entire period. However, the content of ethyl esters increased with storage time and it is in relation with the shelf life. The International Olive Council (IOC) establishes the limits in the content of ethyl esters ≤ 35 ppm. The Coratina oil ceased to be extra virgin quality after 6 months of storage due to its content of ethyl esters (46 ppm), and the Arbequina oil after 9 months (52 ppm).Taking into consideration their content of ethyl esters, both the Arbequina and Coratina oils showed a very short shelf life less than six months. The determination of ethyl ester content proved to be a sensitive method for determining the loss of quality of extra virgin olive oils.

Fatty acids' ethyl and methyl esters are not natural components of edible vegetable oils and therefore should not be present in virgin olive oils. Among the quality requirements for extra virgin olive oils, the International Olive Council (IOC) Norm, 2015 review, set limits for the ethyl ester content at ≤ 435 ppm for the 2014/2015 and 2015/2016 harvests and at ≤ 30 ppm for the 2016/2017 harvest. The purpose of this paper is to: (a) determine the alkyl ester content in two extra virgin olive oils (of the Arbequina and Coratina varieties) as parameters of quality at the moment of their elaboration and to assess the length of their shelf life, over a 12 month period at room temperature; (b) determine extra virgin olive oils' free alcohols content as these may esterify due to the free fatty acids present during storage. After 6 months of storage, the Arbequina oil's ethyl ester content was 32 ppm, and the Coratina's was 46 ppm. As a result, the shelf life for both was only about half a year (labeling usually indicates it must be consumed "before 1 year"). However, parameters related to oxidation (peroxide index, K 232, K 270 and ∆K) remained within the limits set by the International Olive Council (IOC) throughout the year. In conclusion: ethyl ester content is a very fine parameter for assessing the quality of extra virgin in an olive oil and determining the length of its shelf life.

Extra virgin olive oil is recognized as a very stable oil because of its composition in fatty acids and its content in natural antioxidants (tocopherols and polyphenols). In the bibliography are works that address different aspects of this stability, from the duration of its useful life to its performance in the frying of foods. Some works also link their stability with the content of natural antioxidants. For example, Franco et al. (2014) studied the content of phenols and their antioxidant capacity in olive oils of seven different varieties. Baccouri et al. (2008) found a good correlation between the oxidative stability (measured in Rancimat) of the oils studied and the concentration of total phenols and tocopherols.

The virgin oil extraction from avocado Hass was carried using an Abencor pilot scale plant.High-power ultrasound (1.73 MHz) was applied after mixing. High-frequency ultrasound device consists of two transductors which each deliver 30 W/L. Different proportions of water were added before ultrasound treatment (no water added and paste:water relation (1:3, 1:2, 1:1, 2:1, 3:1) and also different ultrasound application times (0, 1, 2, 3, 4, 5, 10, 15, 20 and 25 minutes). The study was carried out by setting one of the two variables considered and changing the values of the other. In the water addition study, ultrasound time was set at 15 min.It was found that oil recovery increased with the percentage of water added. It was decided to employ a ratio of 1:1 to study the influence of ultrasound application time. Under these conditions, it was found that with 1 minute of ultrasound application, recovery increased by 40 % over the process without ultrasound.It was observed that the composition in fatty acids and the content of natural antioxidants (tocopherols and polyphenols) are not affected by the ultrasound application.It is concluded that the application of high-frequency ultrasound with addition of water post malaxing improves recovery of virgin avocado oil without negative effects on the general quality of the oil.