In-Depth Two-Year Study of Phenolic Profile Variability among Olive Oils from Autochthonous and Mediterranean Varieties in Morocco, as Revealed by a LC-MS Chemometric Profiling Approach

Abstract

Olive oil phenolic fraction considerably contributes to the sensory quality and nutritional value of this foodstuff. Herein, the phenolic fraction of 203 olive oil samples extracted from fruits of four autochthonous Moroccan cultivars (“Picholine Marocaine”, “Dahbia”, “Haouzia” and “Menara”), and nine Mediterranean varieties recently introduced in Morocco (“Arbequina”, “Arbosana”, “Cornicabra”, “Frantoio”, “Hojiblanca”, “Koroneiki”, “Manzanilla”, “Picholine de Languedoc” and “Picual”), were explored over two consecutive crop seasons (2012/2013 and 2013/2014) by using liquid chromatography-mass spectrometry. A total of 32 phenolic compounds (and quinic acid), belonging to five chemical classes (secoiridoids, simple phenols, flavonoids, lignans and phenolic acids) were identified and quantified. Phenolic profiling revealed that the determined phenolic compounds showed variety-dependent levels, being, at the same time, significantly affected by the crop season. Moreover, based on the obtained phenolic composition and chemometric linear discriminant analysis, statistical models were obtained allowing a very satisfactory classification and prediction of the varietal origin of the studied oils.

Evaluating Quality Parameters, the Metabolic Profile, and Other Typical Features of Selected Commercial Extra Virgin Olive Oils from Brazil

“…As previously reported, several isomers of the aldehydic form of oleuropein and ligstroside aglycones, decarboxymethyl oleuropein aglycone, and decarboxymethyl ligstroside aglycone can be artificially formed during sample preparation or analysis, either by interaction with methanol (and probably water and/or their mixtures) during extraction or with the silica-based stationary phase in a chromatographic column [ 38 , 39 ]. To circumvent this issue, we adopted a previously described procedure [ 40 , 41 , 42 ], in which the use of methanol was eluded and the quantitative analysis was carried out by calculating each isomer’s content individually, in order to prevent underestimating the total content of these compounds. Lignans were the major group of phenolic compounds in cv.…”

Virgin Olive Oils from Super‐High‐Density Orchards in California: Impact of Cultivar, Harvest Time, and Crop Season on Quality and Chemical Composition

“…The optimal harvest time for super‐high‐density “Arbequina,” “Arbosana,” and “Koroneiki” have shown to be affected by the cultivation area, with different oil accumulation patterns observed for each one of the cultivars. [ 8,9 ] In addition, studies in Tunisia, Morocco, and Spain have shown a lower content in phenolics compounds and a higher concentration of volatiles compared to “Arbosana” and “Koroneiki.” [ 9–12 ]…”

“…While European Union boasts almost 70% of olive oil compounds and a higher concentration of volatiles compared to "Arbosana" and "Koroneiki." [9][10][11][12] While super-high-density plantations have been expanding steadily over the past decade in California, the evolution of fruit and oil compositional parameters with harvest time has not been carefully studied. Furthermore, climate change is adding more variables to seasonality when considering harvesting times.…”

Effect of Ripening on the Phenolic Composition and Mineral Content of Three Varieties of Olive Fruits

“…Two of the most typical olive varieties in Spain are Cornicabra and Picual, known for the excellent quality of their (extra) virgin olive oils. Several studies have been carried out in these two varieties to study the effect of olive ripening on the content of polyphenols in olive fruits [ 10 , 11 , 12 , 13 ] and olive oils [ 10 , 14 , 15 ]. On the other hand, the Cornezuelo variety is less known, and the few studies regarding this variety have focused on olive oil, including organoleptic characteristics, fatty acids, triglycerides, and sterols [ 16 , 17 ].…”