Evaluation of the Shelf Life of Myristica-fragrans Powder-Flavored Oils Obtained through the Application of Two Processes: Infusion and Co-Pressing Technology.

This work aimed to evaluate the impact of enrichment processing on the quality parameters, bioactivity and sensorial aspects of Myristica fragrans (mace)-flavored olive oil storage for one year. The mace powder was added to extra virgin olive oil through two different processes: immediately after crushing the olives by mixing mace (1% weight/weight (w/w)) with the olive paste (MAVOO-M) and by adding mace to extra virgin olive oil (C) (2% w/w) (MAVOO-I). A multi-analytical approach was applied to measure the main qualitative indexes, such as the free acidity, peroxide value and ultraviolet parameters. The total phenolic and carotenoid contents (TPC and TCC, respectively) and α-tocopherol were also evaluated, as well as the sensory attributes. The radical scavenging potential was estimated by using two different in vitro tests, namely, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH). A significant increase in the free acidity parameter was found in all the flavored oils, and particularly in the MAVOO-M (1.27% oleic acid); at the same time, this oil was the sample with the lowest peroxide value (i.e., 9.68 meqO2/kg) after 360 days of storage. At the end of the storage, an increase in L* values was found in both the MAVOO-M and -I vs. the C (43.88 and 43.02, respectively, vs. 42.62). The TCC was strongly influenced by the addition of mace, especially when the infusion process was used. In fact, after one year of storage, the TCC in the MAVOO-I resulted in ~34.7% more than the MAVOO-M. A promising DPPH radical scavenging activity was observed independently by the applied aromatization process, with IC50 values of 19.77 and 17.80 µg/mL for the MAVOO-M and MAVOO-I, respectively. However, this activity decreased during storage, and a similar trend was observed using the ABTS test. In conclusion the infusion as enrichment methodology led to more promising results in terms of functionality compared with the co-mixing one.

Evaluation of Quality Parameters and Functional Activity of Ottobratica Extra Virgin Olive Oil Enriched with Zingiber officinale (Ginger) by Two Different Enrichment Processes during One-Year Storage.

The aim of this work was to evaluate the impact of two enrichment processes on the quality parameters and bioactivity of Ottobratica extra virgin olive oil (EVOO) with ginger during storage. The first procedure was conducted by including ginger powder with olive fruits in the malaxer, and the second by infusion into the EVOO. The obtained oils were stored at room temperature for one year in the dark and periodically analysed. To evaluate the effect on the shelf-life of flavoured olive oils (FVOOs), physical, chemical and sensory parameters were evaluated. The FVOOs were investigated for antioxidant activity through a multi-target approach. The inhibition of lipase and carbohydrate hydrolysing enzymes was analysed. The addition of ginger in the malaxer generated a product that preserved the lowest values of peroxide after storage (10.57 mEq O2 kg-1) and maintained the highest α-tocopherol level (101.16 mg kg-1). The FVOOs, regardless of the enrichment technique used, showed a higher antioxidant activity than EVOO. Generally, a reduction in the inhibitory activity of the carbohydrate inhibitory enzymes was observed, especially after 60 days of storage. The addition of ginger improved the lipase inhibitory effect, especially if added during malaxation, and helped the FVOOs maintain this activity during storage.

Development of a multianalytical strategy for detection of frauds in Coleus forskohlii supplements.

A new multianalytical methodology based on gas chromatography (GC) and liquid chromatography (LC) coupled to mass spectrometry (MS) has been proposed to evaluate frauds affecting the composition of Coleus forskohlii root supplements (FKS). After optimization and validation of chromatographic methods, 24 FKS were analyzed. Forskolin, their main bioactive component, was only found in 50% of the FKS evaluated (in the 0.032-17.1% range), with 27% of these supplements showing concentrations of this bioactive lower than those declared in their labels. Application of this methodology also proved to be successful for the detection of frauds regarding the replacement of C. forskohlii by other vegetable sources (green tea, soy leaves and a plant of the Berberidaceae family) in 17% of supplements analyzed. A study on stability of forskolin under accelerated conditions allowed to rule out its degradation as responsible for the lack of this bioactive or other natural constituents in 25% of FKS evaluated. It can be concluded that the multianalytical methodology here developed is an advantageous alternative to address the wide diversity of frauds affecting these supplements.

A multi-analytical strategy for evaluation of quality and authenticity of artichoke food supplements for overweight control.

Despite the widespread use of artichoke-based food supplements for obesity control (FSOC), studies on evaluation of the quality/authenticity of these commercial products are scarce. To that aim, a new multi-analytical strategy, based on the use of gas chromatography coupled to mass spectrometry (GC-MS) and high performance liquid chromatography coupled to ultraviolet and mass spectrometry detection (HPLC-UV-MS), in combination with chemometrics, has been developed. Twenty-one artichoke FSOC and different bract and leaf extracts (used as reference samples) were analysed. Sugars, inositols, caffeoylquinic acids, dicaffeoylquinic acids, flavonoids and their glycosides were detected in reference samples and in most artichoke FSOC. Low concentrations of bioactives, and the presence of other compounds probably related to heat treatment during manufacturing (difructosyl anhydrides, 3-deoxyglucosone), or to the addition of caloric additives (maltose, maltotriose) or non-declared plants (e.g. pinitol, disaccharides, silybin derivatives) were also detected in some FSOC by either GC-MS or HPLC-UV-MS. Application of Principal Component Analysis to the combined GC-MS + HPLC-UV data matrix, proved that this multi-analytical strategy provides advantages over single analytical techniques for the detection of the wide variety of fraudulent practices affecting authenticity of artichoke FSOC and for assessment of their quality.

Survey of quality indicators in commercial dehydrated fruits.

Physical and chemical quality parameters (dry matter, aw, protein, carbohydrates, vitamin C, 2-furoylmethyl amino acids, rehydration ratio and leaching loss) have been determined in 30 commercial dehydrated fruits (strawberry, blueberry, raspberry, cranberry, cherry, apple, grapefruit, mango, kiwifruit, pineapple, melon, coconut, banana and papaya). For comparison purposes, strawberry samples processed in the laboratory by freeze-drying and by convective drying were used as control samples. Overall quality of dehydrated fruits seemed to be greatly dependent on processing conditions and, in a cluster analysis, samples which were presumably subjected to osmotic dehydration were separated from the rest of fruits. These samples presented the lowest concentration of vitamin C and the highest evolution of Maillard reaction, as evidenced by its high concentration of 2-furoylmethyl amino acids. This is the first study on the usefulness of this combination of chemical and physical indicators to assess the overall quality of commercial dehydrated fruits.

Quality parameters in convective dehydrated carrots blanched by ultrasound and conventional treatment.

The effect of previous ultrasound and conventional blanching treatments on drying and quality parameters (2-furoylmethyl-amino acids -as indicators of lysine and arginine participation in the Maillard reaction-, carbohydrates, total polyphenols, protein profile, rehydration ratio, microstructure changes) of convective dehydrated carrots has been assessed. The most striking feature was the influence of blanching on the subsequent 2-furoylmethyl-amino acid formation during drying, probably due to changes in the protein structure. The highest values of 2-furoylmethyl-amino acids were found in carrots conventionally blanched with water at 95°C for 5 min. However, samples previously treated by ultrasound presented intermediate values of 2-furoylmethyl-amino acids and carbohydrates as compared to the conventionally blanched samples. Dried carrots previously subjected to ultrasound blanching preserved their total polyphenol content and showed rehydration properties, which were even better than those of the freeze-dried control sample. The results obtained here underline the usefulness of 2-furoylmethyl-amino acids as indicators of the damage suffered by carrots during their blanching and subsequent drying.

Prevention of diet-induced obesity by apple polyphenols in Wistar rats through regulation of adipocyte gene expression and DNA methylation patterns.

This study was conducted to determine the mechanisms implicated in the beneficial effects of apple polyphenols (APs) against diet-induced obesity in Wistar rats, described in a previous study from our group. Supplementation of high-fat sucrose diet with AP prevented adiposity increase by inhibition of adipocyte hypertrophy. Rats supplemented with AP exhibited improved glucose tolerance while adipocytes isolated from these rats showed an enhanced lipolytic response to isoproterenol. AP intake led to reduced Lep, Plin, and sterol regulatory element binding transcription factor 1 (Srebf1) mRNA levels and increased aquaporin 7 (Aqp7), adipocyte enhancer binding protein 1 (Aebp1), and peroxisome proliferator-activated receptor gamma co-activator 1 alpha (Ppargc1a) mRNA levels in epididymal adipocytes. In addition, we found different methylation patterns of Aqp7, Lep, Ppargc1a, and Srebf1 promoters in adipocytes from apple-supplemented rats compared to high-fat sucrose fed rats. The administration of AP protects against body weight gain and fat deposition and improves glucose tolerance in rats. We propose that AP exerts the antiobesity effects through the regulation of genes involved in adipogenesis, lipolysis, and fatty acid oxidation, in a process that could be mediated in part by epigenetic mechanisms.

Antifungal and antibacterial activity of the essential oil of Chamaecyparis lawsoniana from Spain.

The essential oils extracted from the young stems and leaves of Chamaecyparis lawsoniana (A.Murray) Parl. have been analysed by Gas Chromatography and Gas Chromatography coupled to Mass Spectrometry. A total of 66 compounds were identified representing around the 99% of the total oil. The oil was richer in monoterpenes than in sesquiterpenes. The only main component was limonene with a percentage composition of 77.7%. The rest of compounds that contribute to the fragrance had percentage composition lower that the 3.0%: p-cymen-7-ol (3.0%), myrcene (2.4%), camphor (2.1%), delta-elemene (1.6%), oplopanonyl acetate (1.6%), methyl perillate (1.3%), terpinen-4-ol (1.0%) and beta-oplopenone 1.0%. The antibacterial and antifungal activity of this oil was also tested against different microorganisms. The only fungus tested, Candida albicans, was very sensitive to the treatment with an inhibition halos of 20mm. The oil was more effective with the Gram (+) than with Gram (-) bacteria. The inhibition halos were 12mm, 12-13mm and 12-13mm for Bacillus subtilis, Staphylococcus aureus and Micrococcus luteus respectively. We report new data of the antibacterial and antifungal activity of the essential oil of this species. The essential oil of C. lawsoniana could be considered as a good natural antibacterial and antifungal agent.

Evaluation of different operation modes of high performance liquid chromatography for the analysis of complex mixtures of neutral oligosaccharides.

Chromatographic methods based on different HPLC operation modes, reverse phase (RP), high performance anion exchange chromatography (HPAEC), graphitized carbon chromatography (GCC) and hydrophilic interaction liquid chromatography (HILIC), have been developed and compared for the analysis of complex mixtures of neutral oligosaccharides with functional properties. Whereas GCC gave the best chromatographic separation of isomeric oligosaccharides with the same molecular weight (R(s) values in the range 1.0-4.0 and 2.4-5.6 for tetra- and pentasaccharides, respectively), HILIC provided the best results for mixtures including oligosaccharides of different degrees of polymerization (R(s) values of maltooligosaccharides between 3.4 and 6.2). Validation of the HILIC LC-MS method proved its utility for the analysis of oligosaccharide mixtures with functional properties: relative standard deviations lower than 10%, LOD's and LOQ's in the range 12.7-130.2 ng mL(-1) and 39.3-402.2 ng mL(-1), respectively, and linearity up to 10-20 µg mL(-1). Quantitative data for fructooligosaccharides, gentiooligosaccharides and dextransucrase cellobiose acceptor oligosaccharides were obtained by using this method.

Essential oil composition of the different parts of Eryngium aquifolium from Spain.

The essential oils from the different parts [inflorescences (E.a.I), stems + leaves (E.a.SL) and roots (E.a.R)] of E. aquifolium Cav. gathered in Cádiz (Spain), have been extracted by steam distillation and analyzed by gas chromatography and gas chromatography coupled to mass spectrometry. Quantitative and qualitative differences have been found between the analyzed plant parts. A total of 107 compounds have been identified. The main constituents were germacrene D (30.3%) and sesquicineole (26.7%) for E.a.I fraction, germacrene D (46.0%) and myrcene (13.8%) in the E.a.SL, while E.a.R showed phyllocladene isomer (63.6%) as a unique major compound. The percentage composition of the other constituents was lower than 5.5% in all the analyzed fractions. In agreement with other Eryngium species, no specific compound could be used as a marker for the chemotaxonomy of E. aquifolium. However, similarities in volatile composition were found between E. aquifolium and other species growing under similar environmental conditions. As far as we know, this is the first report on the essential oil of this species.

Chemical and physicochemical quality parameters in carrots dehydrated by power ultrasound.

Preservation of the quality and bioactivity of carrots dehydrated by power ultrasound (US) under different experimental conditions including prior blanching has been evaluated for the first time by measuring the evolution of the Maillard reaction and the changes in soluble sugars, proteins, total polyphenols, antioxidant activity, and rehydration ability. This study also includes a comparison with a freeze-dried sample and data of commercial dehydrated carrots. The synergic effect of US and temperature (60 degrees C) increased the dehydration rate of carrots (90% moisture loss in only 75 min) while still providing carrots with a level of 2-furoylmethyl-amino acids significantly lower than that of dehydrated commercial samples. Whereas a decrease in the content of reducing soluble sugars was observed with processing temperature, minor carbohydrates (scyllo- and myo-inositol and sedoheptulose) were rather stable, irrespective of the US dehydration parameters. Blanching significantly improved the rehydration ability of US-dehydrated carrots without increasing the loss of soluble sugars by leaching. As supported by the similarity of most quality indicators studied in both US-treated and freeze-dried carrots, the mild processing conditions employed in US dehydration gave rise to premium quality dehydrated carrots.

Chemical composition, antifungal and antibacterial activity of the essential oil of Chamaecyparis nootkatensis from Spain.

The chemical composition of the oil of Chamaecyparis nootkatensis (D. Don) Spach. has been analysed by gas chromatography (GC) and gas chromatography coupled to mass spectrometry (GC-MS). A total of 34 compounds were identified representing more than 90% of the total oil. The oil was richer in monoterpenes than in sesquiterpenes, the major constituents being limonene (53.2%), 6-3-carene (21.0%) and a-pinene (12.2%). The antibacterial and antifungal activities of the oil were also tested against Candida albicans, Bacillus subtilis, Enterobacter aerogenes, Enterococcus faecalis, Escherichia coli, Micrococcus luteus, Pseudomonas aeruginosa, Salmonella sp. and Serratia marcescens. Only two of these, Bacillus subtilis and Candida albicans, were sensitive to the treatment, inhibition zones of 11 and 14 mm diameter being obtained, respectively. As far as we know, this is the first report of the antifungal and antibacterial activity of this species.

Characterization of O-trimethylsilyl oximes of trisaccharides by gas chromatography-mass spectrometry.

Gas chromatography (GC) data (linear retention indices and relative areas) and mass spectra (most representative m/z fragments) of 12 reducing trisaccharides as trimethylsilyl oximes (TMSO) and four non-reducing as trimethylsilyl (TMS) ethers have been described for the first time and related to their structural features. Some trends have been observed: earlier elution of non-reducing compounds and fructotrioses; aldotrioses bearing the reducing end with link in position 6 showing the highest retention. Abundance of several fragment ions and their ratios were useful for trisaccharide characterization; some of these features seem to be useful for the characterization of new trisaccharides.

Study of the precision in the purge-and-trap-gas chromatography-mass spectrometry analysis of volatile compounds in honey.

Data precision in the analysis by purge-and-trap coupled on-line to gas chromatography-mass spectrometry (P&T-GC-MS) of honey volatiles has been studied by statistical analysis. The contribution of non-random factors to dispersion of quantitative results was proven by comparing several statistical parameters (correlation coefficients, principal component analysis (PCA) eigenvalues and loadings) from both experimental and simulated data. PCA was also useful for grouping volatiles with similar dispersion behaviour; these groups being generally related to compounds with common properties or structural features. The use of area ratios improves data precision for compounds within the same group. Results from this study could be used for a better selection of internal standards in quantitative analysis of volatiles by P&T-GC-MS.

Analysis of volatiles in dehydrated carrot samples by solid-phase microextraction followed by GC-MS.

A solid-phase microextraction (SPME)-based method for the GC-MS analysis of volatiles in dehydrated carrot root samples has been developed and the effect of the most important factors (fibre coating, extraction temperature, equilibrium time and extraction time) on the fractionation of different volatiles has been studied. GC-MS chromatograms showed terpenoids relevant to carrot aroma such as alpha-pinene, sabinene, beta-myrcene, limonene, gamma-terpinene, terpinolene, trans-caryophyllene and beta-bisabolene, and several furan derivatives whose origin is discussed in this paper. As an example of application, this methodology has been used for the characterization of volatile composition of industrially dehydrated carrots. SPME followed by GC-MS is shown as an affordable, fast and solvent-free technique which can be performed with low sample amounts and be easily implemented at an industry for quality control purposes.