Evaluation of the physical, antioxidant, and organoleptic properties of biscuits fortified with edible flower powders.

Foods enriched with plants have gradually become an area of increasing research interest because plant ingredients may offer several positive effects on human health and the body. The aim of our study was to develop biscuits fortified with three different types of edible flowers (marigold, lavender, and rose) and examine their physical and antioxidant characteristics, as well as consumer acceptability. The antioxidant properties and characterization of biscuits highlighted that edible flowers may cause increased total polyphenol and total flavonoid yields, as well as DPPH radical scavenging activities. Concerning biscuits fortified with rose petals, the total monomer anthocyanin content was also raised. In addition, the results showed that the antioxidant properties of biscuits increased with increasing concentration (from 2.5% to 5.0%) of edible flowers. Despite this, the consumer acceptability results clearly showed that the addition of marigold and lavender at a concentration of 5.0% caused significantly decreased overall acceptance. We found that the fortification step may increase the spread ratio, which is an important quality attribute of biscuits. We found slight variations in the diameter, thickness, and baking loss parameters of fortified biscuits compared to the control. All in all, the best results were obtained when the biscuits were fortified with rose petals at a concentration of 5%.

Wild Blackberry Fruit (Rubus fruticosus L.) as Potential Functional Ingredient in Food: Ultrasound-Assisted Extraction Optimization, Ripening Period Evaluation, Application in Muffin, and Consumer Acceptance.

The aim of the present study is to evaluate the antioxidant properties of wild blackberry fruits as well as their possible use in powdered form as a functional ingredient. For this, ultrasound-assisted extraction optimization, ripening stage evaluation, and wild blackberry powder incorporation into a real food matrix were applied. The optimum conditions for extraction were as follows: 60% MeOH, 20 min of extraction time, acidification with 0.5% HCl, and a 1:40 g/mL solid-to-solvent ratio, which allowed the following yields: total polyphenol content (TPC): 53.8 mg GAE/g; total flavonoid content (TFC): 5.78 mg QE/g; total monomer anthocyanin content (TMA): 11.2 mg CGE/g; 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity (DPPH): 71.5 mg AAE/g; IC50: 52.3 µg/mL. The study also highlighted that, during the ripening process, the TPC (41.4%), TFC (17.0%), and DPPH levels (66.4%) of the fruits decreased while the TMA yield increased. The incorporation of blackberry powder at different levels (5-20%) increased the TPC, TFC, TMA, and antioxidant properties of muffins. Although the muffins enriched with 20% wild blackberry powder had the best chemical properties (TPC: 3.15 mg GAE/g; TFC: 0.52 mg QE/g; TMA: 0.23 mg CGE/g; DPPH: 1.70 mg AAE/g; IC50: 1.65 mg/mL), the sensory analysis showed that the addition of blackberry fruit at a concentration of 10% to the muffins resulted in the best consumer acceptability.

Examining the Naringin Content and Sensory Characteristics of Functional Chocolate Fortified with Grapefruit Peel Extract.

Grapefruit peel contains a high concentration of naringin- a potent antioxidant with strong bioactive properties. In this study, a new type of functional chocolate fortified with grapefruit peel extract and different concentrations of aqueous methanol and ethanol were evaluated as extraction solvents. A new high-performance liquid chromatography (HPLC) method to analyze the naringin content of the fortified chocolates was developed with a recovery of 107% ± 3.1% and repeatability below 3.5%. A sensory evaluation was conducted to assess the preference for the chocolates among individuals who self-described a preference for bitter flavors. No significant preference was observed in the cases of astringency and aftertaste while the increased bitterness proved to be favorable. However, taste, flavor and overall acceptability were regarded somewhat less favorably. While chocolate proved to be a satisfactory carrier for naringin and had several enjoyable characteristics, further research may focus on improving the organoleptic properties of chocolates fortified by naringin.

The effects of extraction conditions on the antioxidant activities, total polyphenol and monomer anthocyanin contents of six edible fruits growing wild in Hungary.

Although wild fruits are significantly underutilized in most countries, they could be good sources of valuable bioactive compounds with antioxidant properties. Therefore the present study focused on the study of a conventional extraction technique (maceration with shaking; MACS) to extract natural antioxidants and anthocyanin colorants from six edible wild-growing fruits (European crab apple, bilberry, yellow-, red-, and purple-skinned greengage, and quince). One-factor-at-a-time (OFAT) methodology was chosen to investigate the influences of three different parameters (solvent type, extraction time and solvent acidity) on the total polyphenol contents (TPCs), total monomeric anthocyanin (TMA) contents, and antioxidant capacities, specifically ferric reducing power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl radical-scavenging activity (DPPH). After optimization, the recorded TPCs and antioxidant activities proved to be significantly higher for all analyzed fruits when compared to differing extraction conditions. For European crab apple and purple-skinned greengage, the best extraction conditions were a ratio of 80:20 (v/v) EtOH-H2O, 1% (v/v) of HCOOH, and an extraction time of 90 min. In the case of red-skinned greengage, the extraction parameters were the same as the above except for the acid concentration (0.5%; v/v) used. For quince, the optimized conditions required a 50:50 (v/v) EtOH-H2O mixture, an extraction time of 90 min, and 0.5% (v/v) HCOOH concentration. The best conditions for the extraction of bilberry and yellow-skinned greengage were an EtOH-H2O combination of 50:50 (v/v), extraction time of 60 min, and HCOOH concentration of 0.5% (v/v). The highest TPC and antioxidant activity were observed in quince (281-510 mg GAE/100g and 109-395 mg AAE/100g) whereas the lowest were measured in European crab apple (55.9-70.0 mg GAE/100g and 20.1-43.2 mg AAE/100g). Bilberry exhibited the highest TMA content (346 mg CGE/100g). Overall, our results showed that these wild fruits could be a good source of natural antioxidants for the local residents.

Measurement of Naringin from Citrus Fruits by High-Performance Liquid Chromatography - a Review.

Naringin is a flavonoid found primarily in citrus species with especially high concentrations being present in grapefruit (Citrus paradisi), bitter orange (Citrus aurantium), and pomelo (Citrus grandis). Because of its many positive effects on human health, naringin has been the focus of increasing attention in recent years. Recently, conventional extraction methods have been commonly replaced with unconventional methods, such as ultrasound-assisted extraction (UAE) and other, more eco-friendly extraction methods requiring little-to-no environmentally harmful solvents or significantly less energy. Naringin analysis is most commonly done via high-performance liquid chromatography (HPLC), and ultrahigh-performance liquid chromatography (UHPLC) coupled with a mass spectrometer (MS) or a photodiode array (DAD) detector. The aim of this review is to provide an overview of recent trends developments in the extraction, sample preparation, and liquid chromatographic analysis of the compound originating from citrus fruits or their products.

Conventional and nonconventional extraction techniques for optimal extraction processes of rosmarinic acid from six Lamiaceae plants as determined by HPLC-DAD measurement.

The goal of this study was to improve the extraction efficiency of rosmarinic acid (RA) from Lamiaceae herbs (lemon balm, peppermint, oregano, rosemary, sage, and thyme) using various extraction techniques (maceration with stirring, MACS; heat reflux, HRE; and microwave-assisted extraction, MAE) and extraction conditions (solvent acidity, solvent type, extraction time and temperature). The RA content was measured by high-performance liquid chromatography with diode-array detection (HPLC-DAD) under test conditions. Our results showed that extraction with acidified aqueous ethanol (EtOH-H2O-HCl, 70:29:1, v/v/v) was the best choice for the recovery of RA compared to other solvent systems. Further study suggested the following optimal extraction times for the different techniques: 120 min at 25 °C with MACS, 15 min at boiling point with HRE, and 5 min at 50 °C and 80 °C with MAE. Based on our results, we demonstrated that by careful adjustment of the extraction conditions, it is possible to set up a single extraction protocol to extract RA from different plants.

Fast and direct screening of copper in micro-volumes of distilled alcoholic beverages by high-resolution continuum source graphite furnace atomic absorption spectrometry.

HR-CS-GFAAS methods were developed for the fast determination of Cu in domestic and commercially available Hungarian distilled alcoholic beverages (called pálinka), in order to decide if their Cu content exceeds the permissible limit, as legislated by the WHO. Some microliters of samples were directly dispensed into the atomizer. Graphite furnace heating programs, effects/amounts of the Pd modifier, alternative wavelengths (e.g., Cu I 249.2146nm), external calibration and internal standardization methods were studied. Applying a fast graphite furnace heating program without any chemical modifier, the Cu content of a sample could be quantitated within 1.5min. The detection limit of the method is 0.03mg/L. Calibration curves are linear up to 10-15mg/L Cu. Spike-recoveries ranged from 89% to 119% with an average of 100.9±8.5%. Internal calibration could be applied with the assistance of Cr, Fe, and/or Rh standards. The accuracy of the GFAAS results was verified by TXRF analyses.

Determination of ethyl carbamate in wine by high performance liquid chromatography.

Kinetics of pre-column derivatization with 9-xanthydrol for the determination of ethyl carbamate (EC) in wine by a previous high performance liquid chromatographic method with fluorescence detection was studied and further developed. The life-time of the derivatized product and its excitation/absorption spectra were systematically investigated. Using low acidity (pH=2.5 set by phosphate buffers) only 3% of 9-xanthyl ethyl carbamate (XEC) decomposes in ∼48h, allowing a prolonged storage time of the derivatized EC conferring more accurate determination for large sample batches. Detection limit of this method is 3µgL(-1), while its average recovery is 98.5±4.9%. Calibration is linear up to 400µgL(-1). The EC content in 33 Hungarian wine samples ranges from 4.9 to 39.9µgL(-1) (average: 17.7µgL(-1), median: 16.7µgL(-1)), while only three of them was slightly over 30µgL(-1) EC, it being the maximum allowed concentration in countries already having legislation.

Determination of trace elements in lithium niobate crystals by solid sampling and solution-based spectrometry methods.

Solid sampling (SS) graphite furnace atomic absorption spectrometry (GFAAS) and solution-based (SB) methods of GFAAS, flame atomic absorption spectrometry (FAAS), inductively coupled plasma optical emission spectrometry (ICP-OES) and inductively coupled plasma mass spectrometry (ICP-MS) were elaborated and/or optimized for the determination of Cr, Fe and Mn trace elements used as dopants in lithium niobate optical crystals. The calibration of the SS-GFAAS analysis was possible with the application of the three-point-estimation standard addition method, while the SB methods were mostly calibrated against matrix-matched and/or acidic standards. Spectral and non-spectral interferences were studied in SB-GFAAS after digestion of the samples. The SS-GFAAS method required the use of less sensitive spectral lines of the analytes and a higher internal furnace gas (Ar) flow rate to decrease the sensitivity for crystal samples of higher (doped) analyte content. The chemical forms of the matrix produced at various stages of the graphite furnace heating cycle, dispensed either as a solid sample or a solution (after digestion), were studied by means of the X-ray near-edge absorption structure (XANES). These results revealed that the solid matrix vaporized/deposited in the graphite furnace is mostly present in the metallic form, while the dry residue from the solution form mostly vaporized/deposited as the oxide of niobium.

Microanalytical method development for Fe, Cu and Zn determination in colorectal cancer cells.

Microanalytical methods suitable for the determination of Fe, Cu in HT-29 (human colon adenocarcinoma) cells treated with different iron compounds (Fe(II) sulfate, Fe(III) chloride, Fe(III) citrate and Fe(III) transferrin) and cultured in medium supplemented or not with 10% (v/v) fetal calf serum (FCS) by total reflection X-ray fluorescence spectrometry (TXRF) and simultaneous graphite furnace atomic absorption spectrometry (GF-AAS) were developed. The developed TXRF method was also suitable for Zn determination in the samples. The main advantage of the proposed methods is the execution of all sample preparation steps following incubation and prior to the elemental analysis in the same Eppendorf tubes. Sample preparation was performed at microscale (115 µL sample volume) with 65% nitric acid and 30% hydrogen peroxide. According to scanning electron microscopic measurements, the organic matrix of the cell samples could be eliminated to the extent that accurate results were obtained for Cu and Fe by analyzing the same samples by TXRF and GF-AAS. Concerning the iron uptake, HT-29 cells incubated in FCS-free medium contained Fe in cca. 5-50 times higher amounts compared to cells cultured in FCS supplemented medium. Pronounced differences in the iron uptake compared to the iron supply (inorganic vs. organic chelated as well as iron(II) vs. iron(III)) were observed in the case of cell lines incubated in FCS-free medium.

Fast heating induced impulse halogenation of refractory sample components in electrothermal atomic absorption spectrometry by direct injection of a liquid halogenating agent.

A novel electrothermal atomic absorption spectrometry (ETAAS) method was developed for the halogenation of refractory sample components (Er, Nd and Nb) of lithium niobate (LiNbO(3)) and bismuth tellurite (Bi(2)TeO(5)) optical single crystals to overcome memory effects and carry-over. For this purpose, the cleaning step of a regular graphite furnace heating program was replaced with a halogenation cycle. In this cycle, after the graphite tube cooled to room temperature, a 20 µL aliquot of liquid carbon tetrachloride (CCl(4)) was dispensed with a conventional autosampler into the graphite tube. The CCl(4) was partially dried at 80°C under the mini-flow (40 cm(3) min(-1)) condition of the Ar internal furnace gas (IFG), then the residue was decomposed (pyrolyzed) by fast furnace heating at 1900-2100°C under interrupted flow of the IFG. This step was followed by a clean-out stage at 2100°C under the maximum flow of the IFG. The advantage of the present method is that it does not require any alteration to the graphite furnace gas supply system in contrast to most of the formerly introduced halogenation techniques. The effectiveness of the halogenation method was verified with the determination of Er and Nd dopants in the optical crystals. In these analyses, a sensitivity decrease was observed, which was likely due to the enhanced deterioration of the graphite tube surface. Therefore, the application of mathematical correction (resloping) of the calibration was also required. The calibration curves were linear up to 1.5 and 10 µmol L(-1) for Er and Nd, respectively. Characteristic masses of 18 and 241 pg and the limit of detection (LOD) values of 0.017 and 0.27 µmol L(-1) were found for Er and Nd, respectively. These LOD data correspond to 0.68 µmol mol(-1) Er and 11 µmol mol(-1) Nd in solid bismuth tellurite samples. The analytical results were compared with those obtained by a conventional ETAAS method and validated with X-ray fluorescence spectrometry analysis.

Direct sample introduction of wines in graphite furnace atomic absorption spectrometry for the simultaneous determination of arsenic, cadmium, copper and lead content.

A multi-element graphite furnace atomic absorption spectrometry (GFAAS) method was elaborated for the simultaneous determination of As, Cd, Cu, and Pb in wine samples of various sugar contents using the transversally heated graphite atomizer (THGA) with end-capped tubes and integrated graphite platforms (IGPs). For comparative GFAAS analyses, direct injection (i.e., dispensing the sample onto the IGP) and digestion-based (i.e., adding oxidizing agents, such as HNO(3) and/or H(2)O(2) to the sample solutions) methods were optimized with the application of chemical modifiers. The mixture of 5 microg Pd (applied as nitrate) plus 3 microg Mg(NO(3))(2) chemical modifier was proven to be optimal for the present set of analytes and matrix, it allowing the optimal 600 degrees C pyrolysis and 2200 degrees C atomization temperatures, respectively. The IGP of the THGA was pre-heated at 70 degrees C to prevent the sputtering and/or foaming of sample solutions with a high organic content, dispensed together with the modifier solution, which method also improved the reproducibility of the determinations. With the digestion-based method, the recovery ranged between 87 and 122%, while with the direct injection method it was between 96 and 102% for Cd, Cu, and Pb, whereas a lower, compromise recovery of 45-85% was realized for As. The detection limits (LODs) were found to be 5.0, 0.03, 1.2, and 0.8 microg l(-1) for As, Cd, Cu, and Pb, respectively. The characteristic mass (m(0)) data were 24 pg As, 1.3 pg Cd, 13 pg Cu, and 35 pg Pb. The upper limits of the linear calibration range were 100, 2, 100, and 200 microg l(-1) for As, Cd, Cu, and Pb, respectively. The precisions were not worse than 4.8, 3.1, 3.7, and 2.3% for As, Cd, Cu, and Pb, respectively. For arsenic, a higher amount of the modifier (e.g., 20 microg Pd plus 12 microg Mg(NO(3))(2)) could be recommended to overcome the interference from the presence of sulphate and phosphate in wines. Although this method increased the sensitivity for As (m(0)=20 pg), it also enhanced the background noise, thus only a slight improvement in the LOD of As (3.9 microg l(-1)) was realized. For the 35 red and white wine samples studied, the highest metal contents were observed for Cu ranging from 20 to 640 microg l(-1) (average: 148 microg l(-1)), followed by Pb from 6 to 90 microg l(-1) (average: 32.3 microg l(-1)), and Cd from 0.05 to 16.5 microg l(-1) (average: 1.06 microg l(-1)), whereas the As content was below the LOD. This wide fluctuation in the trace metal content could be associated with the origin of wines from various regions (i.e., different trace metal level and/or quality of soil, and/or anthropogenic impact), and with diverse materials (e.g., additives and containers) involved in the wine production processes. The Cu content of wine samples was significantly correlated with Pb, whereas its weak anti-correlation was found with Cd. Interestingly, the level of Pb was anti-correlated with the year of production of the wines. This is likely due to the gradual decrease in the Pb content of soils of vineyards by time, which certainly causes less Pb-uptake of the grape plant, thus a decrease in the Pb content of wines as well.

Study on the simultaneous determination of some essential and toxic trace elements in honey by multi-element graphite furnace atomic absorption spectrometry.

A multi-element graphite furnace atomic absorption spectrometry (GFAAS) method was elaborated and applied for the simultaneous determination of As, Cd, Cr, Cu, and Pb in various kinds of honey samples (acacia, floral, linden, rape, and milkweed) using the transversally heated graphite atomiser (THGA) with end-capped tubes and integrated graphite platforms (IGPs). For comparative GFAAS analysis, direct (without digestion) and indirect (with digestion in a microwave oven) sample preparation procedures were tested. The effects of several chemical modifiers, such as NH(4)H(2)PO(4), NH(4)H(2)PO(4)-Mg(NO(3))(2), and Pd(NO(3))(2)-Mg(NO(3))(2), were studied to obtain optimal pyrolysis and atomization conditions for the set of analytes studied. The most efficient modifier was proved to be the mixture of 5microg Pd (applied as nitrate) plus 3microg Mg(NO(3))(2), allowing the optimal 600 degrees C pyrolysis and 2300 degrees C atomization temperatures. To prevent the sputtering and foaming of the matrix during the drying and pyrolysis steps of the furnace heating program, the sample and modifier solutions (20+5microl, respectively) were dispensed together onto the IGP of the THGA pre-heated at 80 degrees C. The effect of increasing concentration of honey matrix was studied on the integrated absorbance (A(int)) signals of analytes. The A(int) signals of Cr and Pb were not altered up to 10% (m/v) matrix content in the sample solutions. The matrix effect was slightly suppressive on the A(int) signals of As, Cd, and Cu above 2% (m/v) honey concentration. The recovery was found to be ranged between 85 and 115% for Cd, Cr, Cu, and Pb, whereas it was a lower, compromise value of 70-99% for As. The limit of detection (LOD) data were 1, 0.04, 0.09, 0.3, and 0.6microg l(-1) for As, Cd, Cr, Cu, and Pb, respectively, which values correspond to 20, 0.8, 1.8, 5.3, and 12ng g(-1), respectively, in the solid samples. The characteristic masses were found to be 21 pg As, 1.3 pg Cd, 4 pg Cr, 12 pg Cu, and 33 pg Pb. The As, Cd, Cr, Cu, and Pb contents of the studied 42 honey samples varied significantly, i.e. from below the LOD up to 13, 3.3, 109, 445, and 163ng g(-1), respectively.

Determination of sunset yellow in multi-vitamin tablets by photoacoustic spectroscopy and a comparison with alternative methods.

Photoacoustic (PA) spectroscopy in the visible wavelength region was shown to be suitable for a direct (no preparatory steps involved) quantification of sunset yellow (E110) colour in effervescent multi-vitamin tablets. Measurements on powdered tablets containing E110 were performed at 480 nm at which wavelength this synthetic colour shows appreciable absorbance. The PA data obtained were compared to the results acquired by diffuse reflectance spectroscopy and conventional spectrophotometry. Intrinsic simplicity, ease of sampling and rapid response were the most important advantages of the PA technique. In terms of sensitivity the performance of the three methods were comparable.