Search results for "Distillation"
showing 10 items of 184 documents
Influence of the Storage of Cistus ladanifer L. Bales from Mechanised Harvesting on the Essential Oil Yield and Qualitative Composition
2021
Cistus ladanifer is a Mediterranean native plant from which valuable products, such as essential oil, are obtained. Manual harvesting of the plants in wild shrublands is usual during short periods of time. Their mechanised harvesting could increase the volume of harvested plants and prevent fires, further storage of the plants collected being necessary. The objective of this work is to study the influence of the storage period of mechanically harvested bales on the essential oil yield and qualitative composition. The harvesting trials were carried out with an adapted commercial harvester baler and the storage of the bales was performed indoors during 1–7 days, 15–30 days and 100–120 days. A…
Efficiency of Ohmic assisted hydrodistillation for the extraction of essential oil from oregano (Origanum vulgare subsp. viride) spices
2017
Abstract The aim of this work was to investigate the effects of Ohmic heating-assisted hydrodistillation (OAHD), applied at different voltages (100, 150, and 200) V, on the qualitative and quantitative characteristics of extracted essential oil from oregano herb ( Origanum vulgare subsp. viride ), compared to a conventional hydrodistillation (HD) procedure. The compositions of the extracted essential oils (using OAHD and HD) were assessed using gas chromatography - mass spectrometry (GC–MS). A 2,2-diphenyl-1-picrylhydrazyl free radical (DPPH) method was applied in order to evaluate antioxidant activity. The antimicrobial activity as well as the minimum inhibitory concentration (MIC) values …
Assessment of production and qualitative characteristics of different populations of Salvia sclarea L. found in Sicily (Italy)
2021
Salvia sclarea L. is an important industrial crop, valued for its herbal-aromatic properties and high quality essential oils, that is used in food, pharmaceuticals and cosmetics. In this study, carried out from 2009 to 2010, the morphological and production characteristics and essential oil content and composition of three Sicilian populations were studied. In particular, the composition of essential oils extracted from primary and secondary inflorescences using steam distillation was assessed. Morphological, production and qualitative data from the three populations were subjected to analysis of variance and cluster analysis. Regarding the quality of the oils, only the most prevalent compo…
Efficient and reproducible experimental infections of rats with Blastocystis spp.
2018
Although Blastocystis spp. infect probably more than 1 billion people worldwide, their clinical significance is still controversial and their pathophysiology remains poorly understood. In this study, we describe a protocol for an efficient and reproducible model of chronic infection in rats, laying the groundwork for future work to evaluate the pathogenic potential of this parasite. In our experimental conditions, we were unable to infect rats using vacuolar forms of an axenically cultivated ST4 isolate, but we successfully established chronic infections of 4 week-old rats after oral administration of both ST3 and ST4 purified cysts isolated from human stool samples. The infection protocol …
Quality and volatile compounds in red wine at different degrees of dealcoholization by membrane process
2019
This study investigated the effect of different degrees of dealcoholization on volatile compounds, phenols and sensory characteristics of red wine (cv. Montepulciano d’Abruzzo). The wine with an initial alcohol content of 13.2% v/v was partially dealcoholized by membrane process with a decrease of alcohol degree as follows: − 4.9; − 6.3; − 7.8, − 9.2 and − 10.5% v/v. Osmotic distillation has proved effective in preserving a satisfactory odorous profile, as samples with an alcohol residue of 8.3% v/v (− 4.9%) and 6.9% v/v (− 6.3%) showed good esters retention: more than 84% and 82%, respectively. Similarly, colour and taste, evaluated by flavonoids and phenolic compounds, remained almost unc…
Evaluation of the 2-Methoxyethanol as Entrainer in Ethanol–Water and 1-Propanol–Water Mixtures
2013
In this paper, 2-methoxyethanol (commercially known as methyl cellosolve) is proposed as a potential entrainer for extractive distillation processes involving water–alcohol mixtures. The two alcohols studied in this work are ethanol and 1-propanol. Thereby, isobaric vapor–liquid equilibrium (VLE) data at atmospheric pressure have been measured for the ternary systems ethanol + water + 2-methoxyethanol and 1-propanol + water + 2-methoxyethanol. Moreover, data of the binary systems formed by the 2-methoxyethanol and each of the other chemicals used (ethanol, water, 1-propanol) have been obtained. The well-known local composition models Wilson, UNIQUAC, and NRTL have been used to correlate bin…
Volatile components of dry-cured ham
1991
The volatile components of dry-cured ham were isolated by vacuum distillation and analyzed by gas chromatography-mass spectrometry. The structures of 76 molecules were identified by mass spectrometry, cochromatography, or measured Kovats indices. The compounds identified may come from the catabolism of the main constituent parts of the meat (glucids, lipids and protids) during the curing of the hams, from the pig feed, or from technological processes. The volatile compounds extracted from 50 g of ham according to the technique described correspond to a chromatographical surface equivalent to 0.12 mg of the dodecane internal standard, or approximately 2.4 ppm of the weight of the sample. Fla…
Isobaric Vapor–Liquid Equilibria for the Extractive Distillation of Ethanol + Water Mixtures Using 1-Ethyl-3-methylimidazolium Dicyanamide
2011
Isobaric vapor–liquid equilibria (VLE) for the binary systems ethanol + 1-ethyl-3-methylimidazolium dicyanamide ([emim][DCA]) and water + [emim][DCA] as well as the VLE for the ternary system ethanol + water + [emim][DCA] have been obtained at 100 kPa using a recirculating still. The effect of [emim][DCA] on the ethanol + water system has been compared with that produced by another ionic liquid reported in the literature on the basis of the variation of solvent activity coefficients in ionic liquid (IL) + molecular solvent binary systems. From the results, [emim][DCA] appears as one of the best entrainers for the extractive distillation of the ethanol + water mixtures, causing the azeotrope…
Isobaric Vapor−Liquid Equilibria for Binary and Ternary Mixtures of Diisopropyl Ether, 2-Propyl Alcohol, and 3-Methyl-1-Butanol
2008
Consistent vapor−liquid equilibrium data for the binary and ternary systems diisopropyl ether (1) + 2-propyl alcohol (2) + 3-methyl-1-butanol (3) are reported at 101.3 kPa. The diisopropyl ether (1) + 3-methyl-1-butanol (3) system shows positive deviations from ideal behavior, and the 2-propyl alcohol (2) + 3-methyl-1-butanol (3) system exhibits slight deviations from ideal behavior. The activity coefficients and the boiling points were correlated with their compositions by the Wilson, NRTL, UNIQUAC, and Wisniak−Tamir equations. It is shown that these models allow a very good prediction of the phase equilibria of the ternary system using the pertinent parameters of the binary systems. 3-Met…
Phase equilibria involved in extractive distillation of dipropyl ether+1-propyl alcohol using 2-ethoxyethanol as entrainer
2007
Abstract Consistent vapour–liquid equilibrium data at 101.3 kPa have been determined for the ternary system dipropyl ether + 1-propyl alcohol + 2-ethoxyethanol and two constituent binary systems: dipropyl ether + 2-ethoxyethanol and 1-propyl alcohol + 2-ethoxyethanol. The dipropyl ether + 2-ethoxyethanol system shows positive deviations from ideal behaviour and 1-propyl alcohol + 2-ethoxyethanol system exhibits no deviation from ideal behaviour. The activity coefficients and the boiling points were correlated with their compositions by the Wilson, NRTL and UNIQUAC equations. It is shown that the models allow a very good prediction of the phase equilibria of the ternary system using the pert…