Search results for "Veterinary Science"
showing 10 items of 2359 documents
Mycotoxins in cereals and pulses harvested in Latvia by nanoLC-Orbitrap MS
2021
Twenty-seven mycotoxins in unprocessed cereals (n = 110) and pulses (n = 23) harvested in Latvia were analysed by nanoflow liquid chromatography combined with Orbitrap high-resolution mass spectrometry. One or more mycotoxins were found in 99% of the cereals and 78% of the pulses. Deoxynivalenol, zearalenone and T-2 and HT-2 toxins were prevalent in 9 to 86% of the cereals, mostly below their maximum levels as set by the European regulations. Non-regulated type A and B trichothecenes were prevalent in 5 to 87% of the cereals, at concentrations of 0.27–83 µg kg−1 and 1.7–4,781 µg kg−1, respectively. Quantification of emerging mycotoxins was also provided. Enniatins were detected in 94% of th…
Gas chromatography and mass spectroscopy techniques for the detection of chemical contaminants and residues in foods
2017
Gas chromatography-mass spectrometry (GC-MS) is a cornerstone for qualitative and quantitative analysis of food contaminants and residues. It is fast and sensitive, provides a high peak capacity, and allows determination of thermally stable and volatile compounds. Recent research has resulted in better chromatographic columns and methods for sample preparation that enable a significant expansion of the application range of GC-MS, profiling strategies for sample characterization being identified as important future drivers. Newer detection/separation solutions, such as fast chromatography, comprehensive two-dimensional GC (GC × GC), triple quadrupole MS, time-of-flight MS or orbitrap, atmosp…
Evaluation of the representativeness of the odor of beer extracts prior to analysis by GC eluate sniffing
1993
The importance of obtaining and proving that the odor of an extract is representative of the odor of the original product from which it was obtained, before analysis by GC-FID, GC-MS, or GC sniff, is discussed. The sensory methods, such as triangle tests, matching tests, and quantitative analysis, used to determine the representativeness of the odor of an extract are described. Beer extracts obtained by three methods were used to illustrate the interest of the sensory tests. A method using a mixture of XAD resins was proved by sensory analysis to give some extracts with sensory characteristics representative of the particular beers from which they were obtained
Determination of trichothecenes in chicken liver using gas chromatography coupled with triple-quadrupole mass spectrometry
2018
Abstract Chicken meat and edible offal are included in a wide number of preparations in the worldwide cuisine. Among the offal, the liver is one of the most consumed in some countries like Egypt since it is rich in proteins and is an economical source of many essential nutrients for humans. Mycotoxins, secondary toxic metabolites produced by fungi, have the potential to enter human food chain not only with cereal consumption but also through edible tissues from animals fed with mycotoxin-contaminated feed. Accordingly, a rapid method for the determination of eight trichothecenes in chicken liver was developed based on a quick, easy, cheap, effective, rugged and safe (QuEChERS) extraction an…
Development a mitigation strategy of enniatins in pasta under home-cooking conditions
2016
The effect of pasta cooking on the enniatins (ENs) contents was evaluated in white and whole-grain pasta. The cooking of pasta was performed for 10 min in boiling water. ENs were extracted from raw and cooked pasta by Solid-Liquid extraction with acetonitrile, and from cooking water by Dispersive Liquid–Liquid Micro-Extraction (DLLME) with a mixture of acetonitrile and carbone tetrachloride. Mycotoxin analysis was performed by Liquid Chromatography coupled to Tandem Mass Spectrometry. The effect of pasta cooking has a marked influence on the reduction of ENs levels. Reductions of 98–100% for ENA, 94–95% for ENA1, 14–49% for ENB and 53–65% for ENB1 were achieved after the process. ENs were d…
New Alternative in the Methodology of Extraction and Dyeing with Active Molecules Derived from Vegetal Sources
2016
Abstract The general objective of this study refers to the identification of a sustainable and physical methodology of extraction of active compounds, envisaging the preservation of the high purity active natural dye molecule from nut shell (juglone), even under the conditions of an extraction performed in a mixt solvent medium (water-ethanol). The second major objective of the study consists of the application of these above mentioned dyes onto natural and synthetic substrates, thus making a correlation between their colour attributes and the fibrous composition of the substrates they are applied on. The motivation of this research was given by the identification of an improved extraction …
Thermally Induced Isomerisation Kinetics of the 9c11t and 10t12c Conjugated Linoleic Acids in Triacylglycerols as Studied by FT-IR Spectrometry Aided…
2014
Published version of an article from the journal:The Open Spectroscopy Journa. Also available from the publisher:http://dx.doi.org/10.2174/1874383801004010041. Open Access Isomerisation kinetics of the 9c11t and 10t12c Conjugated Linoleic Acids (CLA) in triaclglycerols at isothermal conditions (250, 280 and 325oC) has been studied by infrared spectroscopy. Fifteen micro liter portions of the glycerides were placed in micro glass ampoules and sealed under nitrogen. Several glass tubes containing the same triacylglycerols were then subjected to thermal treatment. The glass tubes were removed at regular time intervals, cut open, and a part of the contents in each glass tube analysed by infrare…
Enzyme-assisted extraction of polyphenol from edible lotus (Nelumbo nucifera) rhizome knot: Ultra-filtration performance and HPLC-MS2 profile
2018
Rhizome knot is always wasted as useless and inedible part of lotus root, despite its abundance of polyphenols. In this work, enzyme-assisted extraction followed by ultra-filtration was investigated to recover polyphenols from rhizome knot. Cellulase and pectinase treatment enhanced the polyphenols extraction. The 100 kDa membrane resulted in better filtration yield than 50 kDa membrane, 3.84% and 3.37%, respectively. With 100 kDa membrane, the highest filtration yield (4.08%) was achieved with a rotational speed of 600 rpm, TMP of 0.3 MPa and pH of 5. Satisfied permeate turbidity ( 90%) were obtained under these conditions. The main polyphenols identified in both rhizome knot extract and p…
Characterisation of phenolic compounds in Algerian honeys by RP-HPLC coupled to electrospray time-of-flight mass spectrometry
2017
Abstract A total of 35 honey samples from different regions of Algeria were studied to determine their phenolic profiles. Phenolic compounds, products of the secondary metabolism of plants, were extracted with amberlite XAD-4 and analysed by liquid chromatography, with diode array detection and electrospray ionisation mass spectrometry in negative ion polarity. By using colorometric assays, Erica honeys showed the highest content of phenolic compounds and flavonoids (245 ± 54 mg GAE/100 g and 29 ± 6 mg QE/100 g, respectively). More than 30 compounds were identified in the honey samples studied including 14 phenolic acids and 16 flavonoids. In general, honey samples showed different chromato…
Quantification of some volatile aromatic compounds of apricot by adding standards
1988
The quantification of twelve volatile aromatic compounds of apricot was realized by adding known amounts of pure compounds directly in the slurry before analysis by vacuum distillation and gas chromatography. This method was compared with the classical technique using an internal standard and was applied to two different apricot cultivars. Large differences were observed between the amounts of volatiles calculated by the two methods. They are due to the differences between the extraction coefficients of the quantified compounds and to the retentions of volatiles on nonvolatile compounds, which may vary according to the polarity.