4,162 research outputs found
Status of the Phase-2 Tracker Upgrade of the CMS experiment at the HL-LHC
No full textThe Phase-2 Upgrade of the CMS experiment is designed to prepare its detectors for operations at the High Luminosity Large Hadron Collider (HL-LHC). The upgraded collider, scheduled to start operations in 2027, will lead to challenging conditions in terms of data throughput, pile-up and radiation. For these reasons the tracker detector will be entirely replaced by a new detector, the Phase-2 tracker. We present the status of the design, test and validation of the components of the Phase-2 tracker, and its read-out, calibration, control, and data processing chains \footnote{Published in "Journal of Physics: Conference Series" as "Luigi Calligaris and on behalf of the CMS collaboration 2020 J. Phys.: Conf. Ser. 1690 012039", doi:10.1088/1742-6596/1690/1/012039.}
Oil Structuring for Improving Healthy and Sustainable Diets: The Case Study of Extra Virgin Olive Oil Oleogelation
No full textThe aim of this PhD research project is to develop novel and sustainable strategies to structure liquid oils into pseudoplastic materials, called oleogels, to be used as saturated fat substitutes or as functional components able to modulate lipolysis during human digestion as well as deliver bioactive lipophilic molecules. In this context, the use of extra virgin olive oil (EVOO) as a target oil to be gelled would be particularly interesting due to its well- recognized health-promoting capacity. In this case study, EVOO-based oleogels were developed by using different gelation strategies. The oleogels, after structural characterization, were in vitro digested to study the impact of oil structure on the free fatty acids (FFA) release and polyphenols’ bioaccessibility.
1. Introduction
In accordance with the PhD thesis project previously described (Ciuffarin, 2021), this poster reports the main results of the following activities:
(A1) Study of strategies for oil structuring (e.g., methods and selection of gelators).
(A3) Evaluation of the effect of oleogelation on the gastrointestinal behavior of oleogels by determining the
bioaccessibility of selected bioactive molecules (e.g., polyphenols) as well as the lipolysis degree by using in vitro digestion methodologies.
2. Materials and Methods
Oleogels were obtained by adding 10 % (w/w) of saturated monoglycerides (MG), rice bran waxes (RW), sunflower waxes (SW), and β-sitosterol/γ-oryzanol mixture (PS) in EVOO heated at temperatures higher than the melting temperatures of the different gelators. Additionally, a whey protein-based oleogel (WP) was prepared by mixing EVOO with a WP aerogel prepared following the methodology of Plazzotta et al. (2020). The final oil content in WP-based oleogels was 80% (w/w). Oleogels were characterized for their structure using a texture analyzer (35 mm-diameter cylindrical probe for 5 mm of distance at a crosshead speed of 1.5 mm/s, TA. XT Plus, Stable Micro Systems Ltd, Godalming, UK) and an accelerated release test by centrifuging samples (10000g for 15 min, Mikro 120, Hettich Zentrifugen, Andreas Hettich GmbH and Co, Tuttlingen, Germany).
Unstructured EVOO and oleogels were then subjected to in vitro digestion according to the protocol proposed by Brodkorb et al. (2019). The FFAs released during digestion were assessed by titration (pH-stat). The bioaccessibility of tyrosol (T) and hydroxytyrosol (HT) was evaluated as the percentage ratio between the concentration of these components included in the micellar phase after intestinal in vitro digestion and their concentration in the undigested sample. The polyphenols were determined by HPLC.
3. Results and Discussion
3.1 Oleogel physical properties
Table 1 shows the oil retention capacity and firmness of the considered oleogels. All the samples presented a very high oil retention capacity upon centrifugation (<99%) despite the different firmness. The MG-based oleogel was the weakest gel, followed by WP, RW, SW, and PS. These mechanical properties can be associated with the
different natures of the networks structuring EVOO. In agreement with the literature, MG, RW, and SW formed a crystalline network (da Pieve et al., 2010; Doan et al., 2015), PS generated a fibrillar structure (Scharfe et al., 2019) and protein aerogels absorbed oil in the protein porous structure (Plazzotta et al., 2021).
3.2 In-vitro digestion: FFA release and bioaccessibility
Figure 1 shows the FFA release as a function of the digestion time
of structured into oleogels and unstructured EVOO. The typical
curve of lipid hydrolysis was obtained. The unstructured oil presented FFA release % of about 68%, followed by PS, SW, RW, and MG with 59.1, 50.8, 50.7, and 42.8% respectively. A different behavior was acquired for WP- based oleogels showing the complete digestion of the oil. These results clearly show that the extent of lipid
lipolysis was significantly affected by oil structure. In the case of liposoluble gelators (i.e., MG, RW, SW, PS),
it can be inferred that the lipase activity was hindered by the presence of a structuring network behaving like a
physical barrier to the access of the enzyme to the substrate sites. On the contrary, WP probably
completely dissolved in the gastrointestinal environment thus favouring the emulsification of the oil and thus the lipase activity. In summary, the results demonstrated that the digestibility of the oil can be steered by selecting the proper oleogelator. In the next part of the study, the bioaccessibility of the major EVOO polyphenols (i.e., tyrosol and hydroxytyrosol) was assessed. Despite the higher content of hydroxytyrosol (HT) in EVOO than tyrosol (T) (HT: 248 mg/kg, T: 96 mg/kg), the bioaccessibility of T was significantly higher than that of HT. This result can be explained by considering the different susceptibility to oxidation of the two molecules during digestion (Alberdi-Cedeño et al., 2020). Moreover, differences were recorded among oleogels. Unstructured oil and WP presented the higher T bioaccessibility values, followed by SW, MG and RW, and PS. Since it is impossible to observe a direct effect of gel strength on polyphenol bioaccessibility, it can be speculated a possible interaction between the polyphenols and oleogel network structures. In fact, as well-known, polyphenols are surface-active molecules with the potentiality to interact with other food components.
In conclusion, the results reported in the present study confirm that oleogelation could be a profitable strategy to modulate lipid digestion while delivering bioactive molecules.
4. References
Alberdi-Cedeño, J., Ibargoitia, M. L., & Guillén, M. D. (2020). Study of the in vitro digestion of olive oil enriched or not with antioxidant phenolic compounds. Relationships between bioaccessibility of main components of different oils and their composition. Antioxidants, 9(6).
Brodkorb, A., Egger, L., Alminger, M., Alvito, P., Assunção, R., Ballance, S., Bohn, T., Bourlieu-Lacanal, C., Boutrou, R., Carrière, F., Clemente, A., Corredig, M., Dupont, D., Dufour, C., Edwards, C., Golding, M., Karakaya, S., Kirkhus, B., le Feunteun, S., ... Recio, I. (2019). INFOGEST static in vitro simulation of gastrointestinal food digestion. Nat. Protoc., 14(4), 991–1014.
da Pieve, S., Calligaris, S., Co, E., Nicoli, M. C., & Marangoni, A. G. (2010). Shear Nanostructuring of monoglyceride organogels. Food Biophys., 5(3), 211–217.
Doan, C. D., van de Walle, D., Dewettinck, K., & Patel, A. R. (2015). Evaluating the oil-gelling properties of natural waxes in rice bran oil: Rheological, thermal, and microstructural study. JAOCS,92(6).
Plazzotta, S., Calligaris, S., & Manzocco, L. (2020). Structural characterization of oleogels from whey protein aerogel particles. Int. Food Res. J., 132, 109099.
Plazzotta, S., Jung, I., Schroeter, B., Subrahmanyam, R. P., Smirnova, I., Calligaris, S., Gurikov, P., & Manzocco, L. (2021). Conversion of whey protein aerogel particles into oleogels: Effect of oil type on structural features. Polym. J., 13(23).
Scharfe, M., Ahmane, Y., Seilert, J., Keim, J., & Flöter, E. (2019). On the Effect of Minor Oil Components on β- Sitosterol/γ-oryzanol Oleogels. Eur. J. Lipid Sci. Technol., 121(8)
EVAPORITE SINKHOLE INVESTIGATIONS IN THE OVARO VILLAGE (NE ITALY)
No full textSinkhole are ephemeral karst feature linked to karstifiable rocks. These phenomena are very common in the Carnian Alps (NE Italy) and represent a severe geo-hazard for locals and human facilities.
Few papers regarding NE Italian sinkhole integrate geomorphological investigations and geo-hazard assessment. Zini et al. (2015) and Calligaris et al. (2015) recently recognized and classified tens of sinkholes proximate to Tagliamento River Valley analyzing their evolution with the contribution of geophysical and hydrogeological techniques. But already in 2009 Calligaris et al., proceeded to a preliminary reconnaissance and identification of these features based also on previous papers by Burelli et al. (2004), by Cucchi and Piano (2002) and Gortani back in 1965.
Since then, only few very detailed investigations were realized on specific areas. At now, the knowledge has been developed after an extensive work done overall regional territory. The study, funded by the Geological Survey of the Friuli Venezia Giulia Region brought out that more than 30 municipalities (among the 221 that make up the Region) are affected by sinkholes. Through this extensive analysis, more than 600 phenomena were identified, georeferenced and classified according to Gutiérrez et al. (2014). One of the areas most affected by this geo-hazard is the Ovaro Village (Fig. 1).
Ovaro is set on an alluvial fan were moraine deposits are also present, in a N-S oriented valley where the Degano River flows. In a territory of about 58 km2 with an elevation between 456 and 2.076 m a.s.l., 90 subsiding areas were identified. The municipality, in the past had some geo-hazard problems linked to sinking features. This is not surprising seen that, in Entrampo, a small hamlet of Ovaro sited in its NW side, close to Degano River, is located an historical and still active gypsum quarry. The evaporitic bedrock is not well exposed in the area, but it is widely present in the subsurface.
Geotechnical and geophysical investigations highlighted its presence at variable depths: from few meters below the surface, until 50 m. Several have been the drilled boreholes and some of them were investigated also using a camera that clearly gave the possibility to identify the presence of cavities in the bedrock. The number of identified voids allowed to understand that the karstification degree is particularly high explaining in this way the presence of a karst surface landscape. From a lithological point of view, the area is characterized by the presence of an evaporitic bedrock (Bellerophon Fm. – Permian in age) mantled by fan deposits mixed with moraine ones. The chalks are saccharoidal and whitish, microcrystalline, poorly cemented where the hypogean karstic features are present. A bedrock with the just described characteristics highlight its poor geotechnical properties, which favor the occurrence of collapse or sagging phenomena that caused and could cause new future instabilities to the existing infrastructures.
Acknowledgements The research activities have been funded by the Regional Geological Survey.
References
Burelli, G., Cleva, S., Cucchi, F., Oberti di Valnera, S. (2004). Stato di evoluzione di sinkholes in alcune aree montane del Friuli Venezia Giulia. 1° Seminario "Stato dell'arte sullo studio dei fenomeni di sinkholes", APAT, Roma, 159-170.
Calligaris, C., Devoto S., Zini, L., Cucchi F. (2015). Evaporite geo-hazard in the Sauris area (Friuli Venezia Giulia Region – Northeast Italy). 14th Sinkhole Conference, NCKRI Symposium, 5-9 October 2015, 465-470, ISBN 978-0-9910009-5-1.
Calligaris, C., Zini, L., Cucchi, F., Stefanelli, S. (2009). Gypsum’s role in the Friuli Venezia Giulia Sinkholes. Proceedings of the 2°Seminario “I sinkholes: gli sprofondamenti catastrofici nell’ambiente naturale ed in quello antropizzato”, ISPRA. Roma, 213-221.
Cucchi, F., Piano, C. (2002). Ipercarsismo superficiale e sepolto nelle evaporiti del Friuli-Venezia-Giulia. Proceedings of Le voragini catastrofiche, un nuovo problema per la Toscana. Edizioni Regione Toscana, Grosseto, 35-41.
Gortani M. (1965). Le doline alluvionali. Natura e Montagna, 3, 120-128.
Gutiérrez F., Parise M., De Waele J., Jourde H. (2014). A review on natural and human-induced geohazards and impacts in karst. Earth-Science Reviews, 138, 61-88.
Venturini C. (2009). Note illustrative della Carta Geologica d’Italia in scala 1:50.000, Foglio 031 Ampezzo. Serv. Geol. D’It., pp. 232.
Venturini C. (2001). Geological Map of the Carnic Alps, western sheet. 1:25.000 scale. SEdizioni del Museo Friulano di Storia Naturale, Pubblicazione no.48, 2006.
Zini L., Calligaris C., Forte E., Petronio L., Zavagno E., Boccali C., Cucchi F. (2015). A multidisciplinary approach in sinkhole analysis: The Quinis village case study (NE-Italy). Engineering Geology, 197, 132-144
Shelf-life prediction of bread sticks by using oxidation indices: a validation study
No full textThe aim of this study was to apply the protocol for the shelf life prediction of bakery products proposed by Calligaris and others (2007a) on bread sticks. The methodology comprises 4 steps: (1) evaluation of the physical properties of fat; (2) performing the accelerated shelf life test; (3) evaluation of sensory acceptance limit and the relevant chemical index limit; (4) setting up the shelf life prediction model. The results allow validating the shelf life prediction methodology proposed. In fact, the peroxide number was found to be a representative index of the quality depletion of bread sticks during their shelf life. In addition, once again by accounting for the changes in the fat physical state, it is possible to set up a modified Arrhenius equation able to describe the temperature dependence of peroxide formation. Finally, a mathematical model to simply and quickly calculate the shelf life of bread sticks has been developed. © 2008 Institute of Food Technologists
shelf life prediction by integration of sensory acceptability data into classic kinetic modelS
No full textLaparoscopic treatment of a non paasitic splenic cyst: case report
No full textJ. LAPAROENDOSCOPIC SURGER
Stereochemistry of ruthenium bis-chelate disulfoxide complexes. A molecular mechanics investigation
No full textApplication of different drying techniques to fresh-cut salad waste to obtain food ingredients rich in antioxidants and with high solvent loading capacity
No full textWastes from iceberg salad fresh-cut processing were submitted to air-drying, freeze-drying, and supercritical-CO2-drying with or without ethanol as co-solvent. Drying was combined with grinding to obtain flours. Samples were analysed for macro- and micro-appearance, particle size, dietary fibre, polyphenol content, antioxidant activity, water vapour sorption, water and oil holding capacity. Air-drying produced a collapsed brown material allowing a flour rich in fibre (>260 g/kg) and polyphenols (3.05 mg GAE/gdw) with antioxidant activity (6.04 OD−3/min/gdw) to be obtained. Freeze-drying maintained vegetable structure and colour while partly retaining polyphenols (1.23 mg GAE/gdw). Supercritical-CO2-drying with ethanol as co-solvent, produced an expanded material able to entrap huge amounts of water and oil (43.2 and 35.2 g of water and oil for g of dry sample). Air-dried salad waste derivatives could be used as functional food ingredients, while supercritical-CO2-dried ones can be exploited as bulking agents and absorbers of oil spills or edible oils. © 2017 Elsevier Lt
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