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Extra virgin olive oil (EVOO) is a cornerstone of the Mediterranean diet. Many studies have highlighted its crucial preventive role against cardiovascular disease, neurodegenerative disorders, metabolic syndrome and cancer, with these effects being due to the synergistic anti-inflammatory and antioxidant activities of minor components, such as polyphenols and tocols. The aim of the present study is to implement new technologies for olive oil mills and develop an efficient large-sized industrial process for the continuous extraction of healthier EVOOs that are enriched with these bioactive compounds. Non-thermal technologies, namely ultrasound (US) and pulsed electric field (PEF), have been tested, separately and in combination, to eliminate the need for traditional malaxation. There is extensive literature to support the efficacy of ultrasound-assisted extraction (UAE) and PEF treatments in EVOO production. A newly designed US device and a PEF industrial chamber have been combined into a single, integrated continuous-flow setup, the performance of which in the extraction of EVOO from green Coratina olives has been evaluated herein. Extraction yields, physico-chemical and organoleptic characteristics, and polyphenol and tocol contents were monitored throughout the trials, and the last three were measured at accelerated aging times (AAT) of 15 and 30 days. The US and combined US-PEF processes not only increased daily oil production (ton/day, by nearly 45%), but also eliminated the need for kneading during malaxation, resulting in significant energy savings (approximately 35%). In addition, these innovations enriched the resulting EVOO with nutritionally relevant minor components (8-12% polyphenols, 3-5% tocols), thereby elevating its quality and market value, as well as overall stability. The introduction of continuous-flow US and PEF technologies is a remarkable innovation for the EVOO industry, as they offer benefits to both producers and consumers. The EVOO resulting from non-thermal continuous-flow production meets the growing demand for healthier, nutrient-enriched products.

The inflorescences of Humulus lupulus L. are the most valuable ingredient in the brewing industry. Only female cones are used as their bitterness and aroma, much associated with beer, are granted by the production of resins and essential oils, respectively. The traditional brewing process for the extraction of the organic volatiles in hops is called dry hopping. It consists of extended maceration at low temperature after the fermentation phase. New extraction technologies can improve extraction rates and product quality while saving time and money. This article proves that multiple-effect fractional condensation under a vacuum is suitable for flavouring applications and especially for performing dry hopping without contamination risks and reductions in hop amounts. This technique leads to the recovery of aqueous aromatic fractions that are very rich in hop sesquiterpenes and monoterpenes. These suspensions are extremely stable when stored at 5-8 °C and avoid degradation even after several months. This feature is crucial for the marketing of non-alcoholic beverages, where the dilution of essential oils is otherwise problematic.

The aim of the present study is to develop a new industrial process for the continuous-flow extraction of virgin olive oil (VOO) using the non-thermal ultrasound (US) and pulsed electric field (PEF) treatments. These technologies have been tested both separately and in combination, with the aim of making the malaxation step unnecessary. The ultrasound-assisted extraction (UAE) and PEF treatments are both effective technologies for VOO production and have been well documented in the literature. The present study combines a new continuous-flow set-up, with four US units and PEF treatment. The industrial-plant prototype is able to improve VOO yields, thanks to powerful non-thermal physical effects (acoustic cavitation and electroporation), from 16.3% up to 18.1%. Moreover, these technologies increased the content of nutritionally relevant minor components, which, in turn, improves VOO quality and its commercial value (overall tocopherols and tocotrienols improved from 271 mg/kg under the conventional process to 314 mg/kg under the US process). The combined UAE and US-PEF process also increased the extraction yield, while overcoming the need for kneading in the malaxation step and saving process water (up to 1512 L per working day). Continuous-flow US and PEF technologies may be a significant innovation for the VOO industry, with benefits both for oil millers and consumers. The VOO obtained via non-thermal continuous-flow production can satisfy the current trend towards healthier nutrient-enriched products.

The involvement of macular preganglionic elements' function, during the neurodegenerative process of multiple sclerosis (MS), is controversial. In this case-control observational and retrospective study, we assessed multifocal electroretinogram (mfERG) responses from 41 healthy Controls, 41 relapsing-remitting MS patients without optic neuritis (ON) (MS-noON Group) and 47 MS patients with ON: 27 with full recovery of high-contrast best corrected visual acuity (BCVA) (MS-ON-G Group) and 20 with poor recovery (between 0.2 and 1 LogMAR) of BCVA, (MS-ON-P Group). In the latter Group, Sd-OCT macular volumes and thicknesses of whole and inner and outer retina were measured. MfERG N1 and P1 implicit times (ITs), and N1-P1 response amplitude densities (RADs), were measured from concentric rings (R) with increasing foveal eccentricity: 0-5° (R1), 5-10° (R2), 10-15° (R3), 15-20° (R4), 20-25° (R5), and from retinal sectors (superior, nasal, inferior and temporal) between 0-15° and 0-25°. In the MS-ON-P Group, mean mfERG RADs detected from R1 (0-5°) and from the central nasal sector (0-15°) were significantly reduced ( p < 0.01) with respect to those of the Control, MS-noON and MS-ON-G Groups. No other significant differences between Groups for any mfERG parameters were found. All Sd-OCT measurements, apart from the inner retina macular volume in the central 1 mm, were significantly reduced in MS-ON-P patients compared to Controls. The functional impairment in the MS-ON-P Group was associated but not correlated with structural changes of the outer and inner retinal layers in corresponding retinal Areas and Sectors. Our results suggest that in MS, exclusively after ON with poor recovery of BCVA, the neurodegenerative process can induce dysfunctional mechanisms involving photoreceptors and bipolar cells of the fovea and of the more central nasal macular area.

Nowadays, approximately 1 billion kg/y of grape stalks, with a remarkable polyphenols content, are produced worldwide. In this paper, the extraction process intensification of polyphenols in water was achieved under ultrasound-assisted recovery, focusing on kinetics and scaling-up factors. Immersion and cup-horn systems were exploited as acoustic cavitation sources, and the total phenolic content (TPC) was chosen to assess the process efficiency. The kinetics were evaluated by Peleg's hyperbolic model, and the effect of both the initial feedstock granulometry and ultrasound size-reduction were determined. The results were compared with conventional extraction methods (data analysis by ANOVA). The best polyphenols yield was obtained after 45 min of sonication, giving between 29.71 and 31.89 mg/g (gallic acid equivalents over the dry matter). The extracts were characterized using HPLC-DAD, UPLC-ESI-MS/MS, DPPH • assay (2,2-diphenyl-1-picrylhydrazyl), TEAC assay (Trolox equivalent antioxidant capacity), and proanthocyanidin content determination. The flow-mode extraction procedure of grape stalks (2 kg) was carried out in a 15 L reactor. A semi-industrial decanter unit and a bag-filter were the keys units of the downstream operations. The resulting particle-free solution underwent nanofiltration on a membrane pilot skid, providing a final polyphenols-enriched stream concentrated up to 355.91%, as shown by the antioxidant activity and TPC., Competing Interests: The authors declare no conflict of interest.