Search results for " Analytical"

Influence of Formulation and Structure of an Oil-in-Water Emulsion on Flavor Release

1999

International audience

Sequential window acquisition of all theoretical fragments versus information dependent acquisition for suspected-screening of pharmaceuticals in sed…

2019

The aquatic ecosystems are dynamic environments often affected directly or indirectly by a myriad of anthropogenic contaminants that need to be properly identified. In this study, liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-QqTOF-MS) suspected-screening was applied to mussels and riverine sediment both, non-spiked and spiked with a mixture of 32 pharmaceuticals. Three data acquisition methods –sequential window acquisition of all theoretical fragment-ion spectra (SWATH), in fix (FSWATH) and variable (VSWATH) window modes and Information Dependent Acquisition (IDA)– were compared to determine the most suitable acquisition technique. The results obtained in the spike…

On-line in-tube solid phase microextraction coupled to capillary liquid chromatography-diode array detection for the analysis of caffeine and its met…

2019

Abstract In-tube solid phase microextraction (IT-SPME) coupled on-line to capillary liquid chromatography with diode array detection provides a simple and fast analytical methodology for the simultaneous quantitation of caffeine and its three primary metabolites (theobromine, paraxanthine and theophylline) in micro samples of serum, saliva and urine matrices. The sample amount required for one analysis was only 2.5 μL of saliva, 6.25 μL of serum or 40 μL of urine, a requirement for its implementation in a hospital laboratory for preterm newborns, where sample availability is a major problem. In standard conditions, 25 μL of diluted saliva or serum (or 100 μL of urine) were processed by IT-S…

Assessment wine aroma persistence by using an in vivo PTR-ToF-MS approach and its relationship with salivary parameters

2019

To better understand wine aroma persistence, the nasal cavity of nine volunteers was monitored by Proton Transfer Reaction-Time of Flight-Mass Spectrometry (PTR-ToF-MS) after they rinsed their mouths with three rosé wines (one control and the same wine supplemented with two tannin extracts) during four minutes. Wines were aromatised with a mixture of five target aroma compounds. Results showed that wine aroma persistence was highly compound-dependent: while esters disappeared very fast, other compounds such as linalool remained in the oral cavity for longer times after wine expectoration. A low effect of tannins (at 50 mg/L) on nasal cavity parameters was observed, with the exception for th…

Relationships between oral characteristics, bolus formation and aroma compound releases during the consumption of fat spread in humans

2011

Source : 13th Weurman Flavour Research Symposium - Zaragoza, Spain - September 27th – 30th, 201; International audience; The release and perception of flavour compounds is an important factor for the acceptance of a food product. It is a complex echanism that depends not only on the food’s chemical composition and structure, but also on in-mouth mechanisms involved in its breakdown. To date, most of the studies have been focused on hard or semi-hard product such as cheese for instance (1, 2). Among the works published on dairy product, fat spreads were not considered while they represent an important market. However these products are particularly interesting by their structure and composit…

Determination of Third-Generation Synthetic Cannabinoids in Oral Fluids.

2020

Abstract A procedure has been developed for the determination of third-generation synthetic cannabinoids in oral fluid samples by using a semi-automated microextraction by packed sorbent (MEPS) procedure and gas chromatography–mass spectrometry (GC–MS) determination. Five synthetic cannabinoids were employed as model compounds 5F-ADB, MMB-CHMICA, THJ-2201, CUMYL-4CN-BINACA and MDMB-CHMCZCA. The most adequate operative conditions for MEPS were evaluated giving quantitative recoveries, from 89 to 124%, in synthetic and field saliva samples spiked with 125 and 250 μg/L of the studied cannabinoids, with the exception of MDMB-CHMCZCA in field saliva samples that provided slightly lower recoverie…

Saliva as a matrix for human biomonitoring in occupational and environmental medicine [Biomonitoring Methods, 2015]

2016

Evaluation of salivary parameters and dental status in adult hemodialysis patients in an indian population.

2018

Background Renal failure is a process that expresses a loss of functional capacity of the nephrons, independently of its etiology. The most widely used technique to combat renal failure is hemodialysis. Renal failure causes various systemic alterations including oral complications such as variations in the flow and composition of the saliva. Caries is a multifactorial disease and impaired stimulated salivary flow rate and buffering capacity are the best-known risk factors. The present study aims to evaluate the salivary pH, buffering capacity and the flow rate of saliva to the DMFT status in adult hemodialysis patients among the Indian population. Material and Methods Twenty healthy individ…

Molecular mechanisms of aroma persistence: From noncovalent interactions between aroma compounds and the oral mucosa to metabolization of aroma compo…

2021

International audience; The present study aims to reveal the molecular mechanisms underlying aroma persistence, as it plays a major role in food appreciation and quality. A multidisciplinary approach including ex vivo experiments using a novel model of oral mucosa and saliva as well as in vivo dynamic instrumental and sensory experiments was applied. Ex vivo results showed a reduction in aroma release between 7 and 86% in the presence of the thin layer of salivary proteins covering the oral mucosa (mucosal pellicle). This reduction was explained by hydrophobic interactions involving the mucosal pellicle and by the ability of oral cells and saliva to metabolize specific aroma compounds. The …

An interlaboratory study as useful tool for proficiency testing of chemical oxygen demand measurements using solid substrates and liquid samples with…

2009

In 2008, the first Proficiency Testing Scheme of Chemical Oxygen Demand (1stCOD-PTADG) was conducted to assess the results obtained for different research groups whose field work is mainly anaerobic digestion. This study was performed using four samples, two solid samples as raw materials and two solid samples to prepare high concentration suspended solid solutions. Invitations were sent to a large number of laboratories, mainly to anaerobic digestion research groups. Finally, thirty labs from sixteen countries agreed to participate, but for different reasons four participants could not send any data. In total, twenty-six results were reported to the COD-PT coordinator. This study showed th…