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Despite having an interesting native olive gene pool and a rapidly emerging olive oil industry, monovarietal extra virgin olive oils (EVOO) from Croatia are relatively unexplored. To investigate the inter-varietal diversity of typical volatile and phenolic profiles of Croatian EVOO, 93 samples from six olive (Olea europaea L.) varieties were subjected to gas chromatography-ion trap mass spectrometry (GC-IT-MS) and ultra-performance liquid chromatography with diode array detection (UPLC-DAD), respectively. Quantitative descriptive sensory analysis was also performed. Analysis of variance extracted many relevant exclusive or partial discriminators between monovarietal EVOOs among the identified volatile compounds and phenols. Successful differentiation model with a 100% correct classification was built by linear discriminant analysis, while the most typical volatiles for each monovarietal EVOO were confirmed by partial least squares discriminant analysis. Diverse typical sensory attributes among the EVOOs were tentatively ascribed to the variations in the composition of volatiles and phenols. It was proven that the approach that comprises GC-IT-MS and UPLC-DAD analysis may provide additional objective information about varietal origin and typicity which successfully complement those obtained by sensory analysis. The approach was characterized as universal in nature, with a significant potential to contribute in strengthening the varietal identities and position on the market of monovarietal and Protected Denomination of Origin (PDO) EVOO.

In order to evaluate the role of intrinsic characteristics of olive cultivars on dynamics of oil quality parameters changes related to the olive fruit fly (Bactrocera oleae (Gmelin)) attack, two specific olive cultivars were compared, Istarska bjelica and Buža. I. bjelica is characterised by late ripening, a lower flesh/stone mass ratio and higher oleic/linoleic ratio, the total phenols content and oil mass fraction compared to Buža. Oil samples were obtained at two harvesting dates, from fruit lots with 0, 25, 50, 75 and 100% of infestation degree, expressed by mass. Oil and water content in olive paste, as well as total phenols, fatty acids composition and standard chemical and sensorial oil quality parameters were determined. At equal maturity level, the cultivar with a higher oil (24 AE 1% vs. 16 AE 1%) and lower water content (54 AE 2% vs. 61 AE 4%) was more susceptible to hydrolytic degradation, while the one with the lower total phenols content (231 AE 32 vs. 575 AE 124 mg/kg) and oleic/linoleic fatty acid ratio (5.7 vs. 9.1) was more liable to oxidative deterioration of oil. Lower susceptibility to negative flavours formation could be related to the absence of ripening induced by fly attack and less favourable environment for larvae growth (higher total phenols content, lower water content and flesh/stone mass ratio).Practical applications: Understanding the impact of olive fly attack is the basis of scientific and practical interest in the production of olives and olive oil. Different intrinsic characteristics of olive cultivars could lead to different susceptibility to oil quality deterioration caused by olive fly attack, which opens a possibility to adjust and minimise pesticide treatments. Knowledge about this topic could contribute to the reduction of costs of olive pests control, as well as to the improvement of quality and food safety concept in olive oil production.

We performed a survey on the yield, quality, and chemical characteristics of virgin olive oils from two olive varieties in Croatian Istria: Frantoio and Ascolana tenera, on Cherry leafroll virus‐infected and virus‐noninfected trees and on two harvest dates. Free acidity, peroxide value, specific spectrophotometric absorptions at 232 and 270 nm, fatty acid composition, total phenols, o‐diphenols, oil color, and pigments were determined. Infected olives had lower oil yield and maturity index versus healthy ones. Oils from infected fruits had significant lower value of K232 and K270 and very elevated total phenols content compared to those obtained from healthy olives. Infected Frantoio gave a lower content of o‐diphenols than the healthy ones, which is in contrast to infected Ascolana that had higher values. The aim of this study is to determine the chemical changes in virgin olive oils from healthy and infected trees related to virus influence. According to our knowledge, this is the first survey on the possible influence of viruses on olive fruits, oil yield, and virgin olive oil quality.Practical applications: There are only few papers which analyze the influence of viruses on crops (especially influence on wine quality) and their effects on yield or other agronomic parameters. This work evaluates for the first time the impact of Cherry leafroll virus on the quality of virgin olive oil obtained from Frantoio and A. tenera varieties in terms of basic parameters related to the hydrolitic and oxidative status, content in antioxidant compounds, and in pigments as well as in fatty acid composition.