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Composizione della farzione lipidica e sua distribuzione nelle diverse parti dell'acino in Vitis vinifera, cv Fortana
No full textEffect of dietary fish oil supplements on livel of n-3 Polynsatutated Fatty Acid, trans Acids and Conjugated linoleic Acid in Ewe Milk
No full textThree groups of ten lactating Sardinian ewes were used between 3rd and 6th month of lactation to determine the effects of supplementing diets with n-3 fatty acids on milk production and milk fat composition. The control group (A) was fed on a mixture of Gramineae hay with a pelleted alfalfa and concentrate; the other groups (13 and C) were given the control ration supplemented with graded levels of fish oil. Milk content of nutritionally important fatty acids (n-3 polyunsaturated fatty acids, PUFA; trans acids and conjugated linoleic acid, CLA) was determined by gas chromatography. Unlike cow milk, milk of normally fed ewes contained detectable quantities of n-3 PUFA and higher amounts of CLA. The supplementation with fish oil resulted in an increased milk fat levels of n-3 PUFA, CLA and trans isomers. There was a positive correlation (R-2 = 0.964) between the trans and n-3 fatty acid content in ewe milk, and a close positive correlation (R-2 = 0.996) between CLA and trans monoenoic fatty acid contents. PUFA supplementation resulted in a slightly, but not statistically significative, decrease of milk fat percentage. On the contrary, dietary fish oil markedly affected milk production: ewes fed on the n-3 supplemented diet produced more milk than the ewes fed with the control diet
Application of the gas chromatography technique in the characterization and authentication of food products
No full textGas chromatography coupled with mass spectrometry (GC-MS) has extensive applications for food characterization and authentication. Due to the high thermal stability of lipophilic compounds, GC/MS lipidomic profiling of foods is a powerful approach for food authentication and characterization. Moreover, GC/ MS volatilomic is a tool to discriminate samples in groups and identify specific biomarkers that are crucial for quality and/or authenticity assessment. The volatile organic compounds (VOCs) in food, especially in honey, wine, and olive oil, are being widely assessed by using GC-MS coupled with solid-phase microextraction (SPME). This chapter gives an overview of the applications of GC-MS lipidomic (fatty acids, triacylglycerols, phytosterols, and n-alkanes) and volatilomic profiling, which has powerful applications in food characterization and authentication
Identification of furan fatty acids in seafood [Identificazione degli acidi grassi furanici nei prodotti ittici]
No full textFuran fatty acids (FFA) are characterized by a furan ring, which carries an unbranched fatty acid chain with 9, 11 or 13 carbon atoms in one α-position and a short straight-chain alkyl group with 3 or 5 carbon atoms in the other α-position. The β-positions of the furan ring can be substituted with two methyl residue or just with one methyl group in the β-position adjacent to the long aliphatic chain. The structure of furan fatty acids is similar to that of some prostaglandins (a five-membered ring with an alkyl chain and an alkyl carboxylic chain). The biological role of the FFA is still not clear, but it has been pointed out that FFA act as antioxidants as they prevent linoleic acid oxidation. The connection between consumption of fish rich in FFA and protection against coronary heart disease mortality has been confirmed in several research studies. In the present study, the fatty acid profile of six species of Adriatic fishes (european pilchard, european anchovy, european hake, horse mackerel, common sole, atlantic mackerel), three species of freshwater fish (perch, indigenous catfish, trout) and three molluscs (clam, mussel, oyster) were determined. The identification of different FFA obtained from muscle, liver, testes, ovaries, eyes and brain was carried out using comprehensive bidimensional gaschromatography coupled on-line with mass spectrometry. The identified FFA were both the saturated series 10,13-epoxy-11-methyloctadeca-10,12-dienoic acid [MonoMe(9,5)], 10,13-epoxy-11,12-dimethyloctadeca-10,12-dienoic acid [DiMe(9,5)], 12,15-epoxy-13,14-dimethyloctadeca-12,14-dienoic acid [DiMe(11,3)], 12,15-epoxy-13-methyleicosa-12,14-dienoic acid [MonoMe(11,5)], 12,15-epoxy-13,14-dimethyleicosa-12,14-dienoic acid [DiMe(11,5)], 14,17-epoxy-15,16-dimethyldocosa-14,16-dienoic acid [DiMe(13,5)], and the unsaturated series 12,15-epoxy-13,14-dimethyleicosa-12,15,16-trienoic acid [DiMe(11,5:1)], 12,15-epoxy-13,14-dimethyleicosa-10,12,14-trienoic acid [DiMe(11:1,5)]. The ubiquitary FFA were [MonoMe(9,5)], [DiMe(11,3)], [MonoMe(11,5)] and [DiMe(11,5)]. FFA were absent in the molluscs and in the indigenous catfish. The unsaturated FFA were absent in the testes and ovaries of european anchovy and european hak
Is a low concentration of Linoleic Acid related to the extended longevity of the Queen honeybee?
No full textLifespan has been a topic of scientific interest for about a century and, in this regard, hundreds of theories have been expressed, calling into question numerous causes of aging, but none of which appears to be decisive. Different species can have hugely different species-specific life spans, but several eusocial species, e.g. honey bees, show very large differences in infra-specific longevity, that is, of individuals. One of the most widely accepted theory remains that of free radicals formulated by Dennis Harmann in 1956 in the historical work "Aging: A Theory based on Free Radical and Radiation Chemistry" (1) and in the following works, where the hypothesis foresees the existence of a strong metabolic activity in the production of free radicals, both on polyunsaturated fatty acids and on proteins with accumulation of oxidized products and damage at mitochondrial level. The effects of peroxidative damage seem to emerge as one of the factors most influencing lifespan. None of the works related to this longstanding problem, however, takes into consideration Linoleic Acid (C18: 2 n-6) as a central element among membrane fatty acids in the involvement of its peroxidation in relation to lifespan. In the examination of the main metabolic responsibilities of Linoleic Acid, attention is focused on the particular role that it, an essential fatty acid, could have as a determining element in the lifespan of worker honeybees with respect to the queen honeybee. Highlights. >Linoleic Acid is an essential fatty acid for mammalian life. >Linoleic Acid occupies a central position in the vital dynamics of animal and human organisms. >Linoleic Acid has the maximum "bulk" in the space within cellular membranes when compared to all the other polyunsaturated fatty acids. >High concentrations of Linoleic Acid can increase the risks of oxidation of Linoleic Acid itself by increasing the peroxidation index, more linked to Linoleic Acid rather than to other polyunsaturated fatty acids
Comprehensive multidimensional gas chromatography in the analysis of food lipids [La gas-cromatografia multidimensionale nell'analisi dei lipidi alimentari]
No full textThe use of comprehensive gas chromatography (GCxGC) is a very useful approach in order to obtain a high resolution separation of complex samples.With comprehensive GCxGC (unlike "heart-cut" 2D GC) the whole sample injected into the system is subjected to two different stationary phases, resulting in a more effective separation than that obtained with conventional one-dimensional (1-D) GC. GCxGC is usually coupled on-line with mass spectrometry, since the resulting bidimensional chromatographic trace needs unambiguous peak identification. The main object of this study was the application of GCxGC/MS to the analysis of both saponifiable and unsaponifiable lipid fractions of different edible matrices. The fatty acids of pomegranate seed oil (Punica granatum), European anchovy's brain (Sardina pilchardus), Berberè (a mix of spices) and the not-saponifiable fraction of Coffea var. robusta were characterized by comprehensive multidimensional gas chromatography with a non-polar (5% phenyl polysiloxane)/medium polar (50% phenyl poly-siloxane) column set equipped with a quadrupole mass-spectrometer
Impact of mild oven cooking treatments on carotenoids and tocopherols of cheddar and depurple cauliflower (Brassica oleracea L. var. Botrytis)
Full text linkThe effect of steam and sous-vide oven procedures on liposoluble antioxidants of colored cauliflower (orange and purple) was assessed for the first time and compared with domestic practice (boiling). In raw samples, the total carotenoid content was 10-fold higher in Cheddar than in Depurple (20.9 ± 2.1 vs. 2.3 ± 0.5 mg/kg dry weight), whereas the level of tocopherols was similar (28.5 ± 4.4 vs. 33 ± 5.2 mg/kg dry weight). The Cheddar liposoluble antioxidant matter contained violaxanthin, neoxanthin, α-carotene and δ-tocopherol, not detected in Depurple. All tests increased the bioactive compounds extractability with steam oven and sous-vide displaying similar effects, lower than boiling. In boiled Cheddar cauliflower, the total carotenoids and tocopherols contents increased with cooking time until they were 13-fold and 6-fold more than in raw cauliflower, respectively. Conversely, in the Depurple variety, contents increased by half with respect to the orange variety. However, from a nutritional point of view, no differences were revealed among the three different cooking treatments in terms of vitamin A and E levels expressed in μg/100 g of fresh vegetable because of the higher water content of boiled samples that must be considered when evaluating the effect of thermal treatment on cauliflower nutritional traits
Eleven monovarietal extra virgin olive oils from olives grown and processed under the same conditions: Effect of the cultivar on the chemical composition and sensory traits
No full textEleven Italian monovarietal extra virgin olive oils (MEVOOs) (Carboncella, Coratina, Frantoio, Leccino, Marzio, Maurino, Moraiolo, Piantone di Falerone, Pendolino, Rosciola, Sargano di Fermo) from olives grown in the same experimental olive orchard, under the same conditions (fertilization, irrigation), and processed with the same technology (three-way continuous plant) were investigated. As a result, the impact of the olive cultivar on fatty acid and triacylglycerols composition, oxidative stability, polar phenolic profile and sensory properties (panel test) of the oil was assessed. Pendolino, Maurino and Marzio oils presented the highest levels (p < 0.01) of palmitic, linoleic and linolenic acids % and the lowest oleic:linoleic ratio. Within triacylglycerols, triolein (OOO) strongly varied among the oils, with Coratina and Leccino having the highest content. Frantoio showed the lowest 1-Stearoyl-2-palmitoyl-3-oleylglycerol and 1,3-Distearoyl-2-oleylglycerol amounts. Rosciola showed the highest level (p < 0.01) for two of the most abundant secoiridoid derivatives (the dialdehydic forms of decarboxymethyl elenolic acid linked to hydroxytyrosol and tyrosol). A good correlation was found between total phenolic content and oxidative stability, indicating Marzio and Leccino respectively as the richest and poorest genotypes. Sensory variability among varieties was mainly linked to perceived bitterness, pungency and fruitiness, while no effects were found on secondary flavors
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