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The bitter orange flower oil (or nerolì) is an essential product, largely used in perfumery. Nerolì is obtained by hydrodistillation or steam distillation, from the flowers of bitter orange ( Citrus aurantium L.). Since a long time nerolì production is limited and its cost on the market is considerably high. The annual production in Tunisia and Morocco is ca. 1500 Kg, representing more than 90% of the worldwide production. A small amount of nerolì is also produced in Egypt, Spain and Comorros (not exceeding 150 kg totally). Due to the high cost, the producers and the users have tried to obtain less expensive products, with odor characters close to that of nerolì oil to be used as substitute and sometimes as adulterants of the genuine oil. In this study are investigated five samples of Egyptian nerolì oils produced in 2008 and 2009, in the same industrial plant, declared genuine by the producer. For all the samples the composition was determined by GC/FID and by GC/MS-LRI; the samples were also analyzed by esGC to determine the enantiomeric distribution of twelve volatiles and by GC-C-IRMS for the determination of the δ 13CVPDB values of some mono and sesquiterpene hydrocarbons, alcohols and esters. The analytical procedures allowed to quantitatively determining 86 components. In particular the variation of the composition seems to be dependent on the period of production. In fact, the amount of linalool decreases from March to April while linalyl acetate presents an opposite trend, increasing in the same period. The RSD determined for the δ 13CVPDB are very small (max. 3.89%), ensuring the authenticity of all samples. The results are also discussed in function of the limits provided by the European Pharmacopoeia (EP) (2004), AFNOR (1995) and ISO (2002) regulations for genuine nerolì oils.

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The task of lipid analysis has always challenged separation scientists, and new techniques in chromatography were often developed for the separation of lipids; however, no single technique or methodology is yet capable of affording a comprehensive screening of all lipid species and classes. This review acquaints the role of supercritical fluid chromatography within the field of lipid analysis, from the early developed capillary separations based on pure CO , to the most recent techniques employing packed columns under subcritical conditions, including the niche multidimensional techniques using supercritical fluids in at least one of the separation dimensions. A short history of supercritical fluid chromatography will be introduced first, from its early popularity in the late 1980s, to the sudden fall and oblivion until the last decade, experiencing a regain of interest within the chromatographic community. Afterwards, the subject of lipid nomenclature and classification will be briefly dealt with, before discussing the main applications of supercritical fluid chromatography for food analysis, according to the specific class of lipids.

The task of lipid analysis and profiling is taking centre stage in many research fields and as a consequence, there has been an intense effort to develop suitable methodologies to discover, identify, and quantify lipids in the systems investigated. Given the high complexity and diversity of the lipidome, researchers have been challenged to afford thorough knowledge of all the lipid species in a given sample, by gathering the data obtained by complementary analytical techniques. In this research, an "omic" approach was developed to quickly fingerprint lipids in the Mediterranean mussel (Mytilus galloprovincialis), by exploiting multidimensional and hyphenated techniques. In detail, two-dimensional comprehensive hydrophilic interaction liquid chromatography coupled to reversed-phase liquid chromatography afforded both class-type separation and lipid assignment within the total lipid species in the sample, by the coupling of a 2.1-mm I.D. partially porous stationary phase in the first dimension, to a short (50 mm) monodisperse octadecylsilica secondary column; individual molecular species were afterwards identified by means of their ion trap-time of flight mass spectra obtained by electrospray ionization. More than 200 neutral and polar lipids were identified, and among the latter, phosphatydylcholine and phosphatydylethanolamine were the most represented classes, together with their mono-acylated forms, plasmanyl and plasmenyl derivatives. Subsequently, separation of the saturated and unsaturated isomers of the fatty acids (including the saturated C16:0 and the polyunsaturated C22:6) in the offline collected phospholipid fractions was accomplished by gas chromatography analysis of the corresponding methyl esters, on a 200 m × 0.25 mm, 0.2 μm d ionic liquid column.

Original PaperFast gas chromatography-full scan quadrupole mass spectrometry for the determination of allergens in fragrancesThe Scientific Committee for Cosmetics and NonFood Products in the 7th Amendment to the European Cosmetics Directive established 26 fragrance components, widely used in cosmetic products, as being responsible for a series of contact allergies (Directive 2003/15/EC, Official Journal of the European Union, L66/26, 11.3.2003). The regulation foresees that any allergen, present in excess of 100 mg/kg in rinse-off and of 10 mg/kg in leave-on formulations, must be reported on the label of the product. The present research reports a fast GC-full scan quadrupole mass spectrometric method (under 5 min) for the qualitative/quantitative analysis of allergens in perfumes. Reliable peak identification was achieved through a twin-filtered MS library matching procedure, considering a minimum degree of spectral similarity (90%) and retention data (a linear retention index window was applied). Peak quantification was carried out by using a specific extracted ion. In case a suspected allergen fell within its retention time window but presented a low degree of spectral purity (a 90%), analyte determination was achieved by using three extracted ions (one quantifier and two qualifiers). The fast GC-MS method was validated in terms of intraday retention time and peak area precision, LODs and LOQs, and method linearity. Finally, peak skewing was also evaluated and was within more than acceptable limits.

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