Lipid profile and fatty acid composition of marine fish species from Northeast coast of Brazil.

Total lipid content, fatty acid composition and nutritional profile of lipid fraction of fourteen fish species from the Brazilian Northeastern coast were evaluated. Lipid content was determined by Bligh and Dyer methodology, whereas the fatty acid composition was determined by gas chromatography with flame ionization detector. The indices of atherogenicity, thrombogenicity and hypocholesterolemic/hypercholesterolemic ratio were used to evaluate the nutritional quality of lipid fraction. The total lipid content ranged from 0.25 to 3.09%, with higher values in L. synagris. A significant difference (p < 0.05) were noted in fatty acids composition between the fourteen fish species. PUFA were the major fatty acids in twelve of fourteen species and C. leiarchus showed the highest content. The n-3 content ranged from 69.83 to 270.62 mg g-1 of total lipids, being EPA and DHA the major fatty acids in most of the species studied. The species L. synagris, M. bonaci and S. brasiliensis exceeded the WHO daily intake recommendation of 250 mg per day from those fatty acids. The quality indexes of the lipid fraction as well as the n-6/n-3 and PUFA/SFA ratios indicated that all fish species can be healthy nutritional options, and can bring many benefits to human health. The principal component analysis resulted in a two-principal-component model that described 79.78% of data variance. Also, it highlighted that despite the differences between the breeding strategies of fish families, the species could be grouped according to their similarity in fatty acids composition.

Direct infusion electrospray ionisation mass spectrometry applied in the detection of adulteration of coconut oil with palm kernel oil.

Coconut oil has properties that are beneficial to human health. It assists in reducing total cholesterol, triacylglycerol (TAG), phospholipids, low-density lipoprotein (LDL) cholesterol, and very low-density lipoprotein (VLDL) cholesterol in serum and tissues. So its production, and consequently consumption, have increased in recent years. However, it has been a target for intentional adulteration with lower priced oils and fats, such as soybean oil and palm kernel oil (PKO). Coconut oil (CO) and PKO have similar chemical and physical characteristics that make it difficult to verify adulteration of CO with PKO. This study demonstrates a simple, sensitive, and fast technique that uses direct infusion electrospray ionisation mass spectrometry (ESI-MS) in conjunction with principal component analysis (PCA), in order to detect CO adulterated with PKO. Among the seven commercial coconut oil samples analysed, three were adulterated with PKO. Therefore, the suggested direct infusion ESI-MS method can be used in routine analysis to guarantee the quality of coconut oil.

Determination of acrylamide in brewed coffee by dispersive liquid-liquid microextraction (DLLME) and ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS).

This work has proposed the application of optimized dispersive liquid-liquid microextraction (DLLME) in order to extract acrylamide from brewed coffee samples for its subsequent determination by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). DLLME achieved superior results employing 300 µL of brewed coffee, 100 µL of dichloromethane, 400 µL of acetonitrile and without sodium chloride addition. Quantitative analyses were carried out by the standard addition method, and the limits of detection and quantification were 0.9 and 3.0 µg L-1, respectively. Recoveries ranged from 97 to 106%, and the intra- and inter-assay precisions ranged from 6 to 9%. The proposed analytical method was applied to seventeen brewed coffee samples prepared in a filter coffee maker, and acrylamide amounts varied from 10.5 to 28.5 µg L-1. Therefore, the suggested DLLME-UPLC-MS/MS method is promising for routine analysis in order to guarantee the quality control of acrylamide in brewed coffee.

Rapid methodology via mass spectrometry to quantify addition of soybean oil in extra virgin olive oil: A comparison with traditional methods adopted by food industry to identify fraud.

Fast and innovative methodology to monitors the addition of soybean oil in extra virgin olive oil was developed employing ESI-MS with ionization operating in positive mode. A certified extra virgin olive oil and refined soybean oil samples were analyzed by direct infusion, the identification of a natural lipid marker present only in soybean oil (m/z 886.68 [TAG+NH4]+) was possible. The certified extra virgin olive oil was purposely adulterated with soybean oil in different levels (1, 5, 10, 20, 50, 70, 90%) being possible to observe that the new methodology is able to detect even small fraud concentration, such as 1% (v/v). Additionally, commercial samples were analyzed and were observed the addition of soybean oil as a common fraud in this segment. This powerful analytical method proposed could be applied as routine analysis by control organization, as well as food industries, considering its pronounced advantages; simplicity, rapidity, elevated detectability and minor amounts of sample and solvent consumed.