Three different flavoring methods of olive oil were tested employing two different herbs, thyme and oregano. The traditional method consist in the infusion of herbs into the oil. A second scarcely diffused method is based on the addition of herbs to the crushed olives before the malaxation step during the extraction process. The third innovative method is the implementation of the ultrasound before the olive paste malaxation. The objective of the study is to verify the effect of the treatments on the quality of the product, assessed by means of the chemical characteristics, the phenol composition and the radical scavenging activity of the resulting oils. The less favorable method was the addition of herbs directly to the oil. A positive effect was achieved by the addition of herbs to the olive paste and other advantages were attained by the employment of ultrasound. These last two methods allow to produce oils "ready to sell", instead the infused oils need to be filtered. Moreover, the flavoring methods applied during the extraction process determine a significant increment of phenolic content and radical scavenging activity of olive oils. The increments were higher when oregano is used instead of thyme. Ultrasound inhibited the olive polyphenoloxidase, the endogenous enzyme responsible for olive oil phenol oxidation. This treatment of olive paste mixed with herbs before malaxation was revealed as the most favorable method due to the best efficiency, reduced time consumption and minor labor, enhancing the product quality of flavored olive oil.

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Negroamaro is an autochthonous wine grape variety of Southern Italy, which is becoming very important for the Italian wine market. The wine aroma is primary affected by the chemical composition of grapes, which can be influenced also by agronomic practices such as soil management. In this study, the free and bound aroma characterization was performed by gas chromatography-mass spectrometry analyses, and the influence of two soil managements (cover cropping and soil tillage) was evaluated. A total of 40 volatile compounds were observed in the wine samples. Alcohols (55.7 mg/L), fatty acids (7.0 mg/L) and esters (6.6 mg/L) were found as the main classes in Negroamaro wine. The results showed that the aroma composition of Negroamaro wine was positively affected by soil tillage probably because of the higher water stress (ψ(s)) recorded in the vines from this treatment. Indeed, among the free volatile compounds, higher contents of esters, carboxylic acids, alcohols, phenolics and acetamides together with lower contents of sulfurs compounds were found in soil tillage wine. Conversely, no difference was observed in glycoside volatile compounds.

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Summary The aim of this study was to assess the impact of some viticultural practices (VP) and winemaking technologies (WT) on phenolic composition and sensory characteristics of Negroamaro wines produced in Apulia, Southern Italy. Among VP, two soil management (cover crop and soil tillage) and two training systems (bilateral cordon and unilateral cordon) were compared, whereas among WT, three vinifications were tested: control (traditional, 7 days of maceration at 25 °C with two daily punching‐down), cryomaceration (24 h at 0 °C using dry ice) and ultrasound (37 kHz, 150 W, 15 min at 30 °C). Results showed that cover cropping decreased the concentration of flavonoids, whereas bilateral cordon training led to an increase of flavonoids and total polyphenols. Among technologies applied, the cryomaceration led to enrichment in anthocyanins and to impoverishment in total polyphenols, whereas ultrasound treatment improved the extraction of all phenol classes. Cryomacerated wines from the combination soil tillage and unilateral cordon were characterised by the best olfactory and gustatory sensory characteristics. Cryomaceration increased the notes of soft fruits and liquorice, whereas ultrasonic treatment did increase descriptors of violet, soft fruits and black pepper.

The aim of virgin olive oil elaboration process is to obtain the highest recovery of the best quality oil from the fruits. The aim of the researchers is to understand the key elements that allow to modulate the complex series of physical, physico-chemical, chemical and biochemical transformations in order to develop innovative and sustainable plant solutions able to increase simultaneously both yield and quality of product. The basic principles applied also in the newest olive oil industrial plants still follow the technical knowledge which have been empirically learned by humans thousands of years ago. In fact, it is well known that three factors, mixing, water adding and warming, are the three macroscopic driving forces able to favour the separation of the oily phase from the mass of crushed olives. In this consolidated scenario, can new elements emerge? The whole process should be considered more than a simple extraction of the oil present in fruit cells, but a complex elaboration of a product, which is depleted and enriched of both constitutive and neo-synthesised compounds through complex phenomena only in part discovered. In fact, while it is evident that numerous studies have been conducted to elucidate the behaviour of olive paste during virgin olive oil extraction process, a key conclusion is that the current level of understanding can be improved further by means the development of more rigorous researches with more focused targets aimed to understand the rheological changes, the coalescence phenomena, the changes in hydrophobic and hydrophilic phenomena, the partition equilibrium of minor compounds between aqueous and oily phases and, last but not least, the favourable and unfavourable enzymatic reactions. This paper provides an analysis of the present research field and its strengths and weaknesses are discussed. Potentially important future directions for research are also proposed

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