Degradation characteristics of proteins in cheonggukjang (fermented unsalted soybean paste) prepared with various soybean cultivars

In order to select the most ideal soybean cultivars for producing cheonggukjang, the protein degradation characteristics of cheonggukjangs prepared with 30 different soybean cultivars were compared. Cheonggukjang prepared with ‘Nampung’ (18.00±0.28%) and ‘Sohwang’ (17.91±0.63%) soybeans showed the highest contents of viscous substances. Acidic-protease activity was highest (590.24±2.92 μg/mL) in cheonggukjang prepared with small ‘Pungsannalmul’ soybeans. Neutral-protease activity was highest (528.13±3.11 and 527.36±0.44 μg/mL, respectively) in cheonggukjang prepared with ‘Singi’ and ‘Nampung’ soybeans. Cheonggukjang prepared with ‘Wonkwang’ and ‘Sohwang’ soybeans had amino-type nitrogen contents of 780.50±2.92 and 729.95±1.07 mg%, respectively. Glutamic acid, which is a major component of viscous substances, was also detected. Although total free amino acid levels in cheonggukjang prepared with ‘Daewon’ and ‘Wonkwang’ soybeans measured 2,551.21 and 2,340.02 mg%, respectively, cheonggukjang prepared with black soybeans exhibited low levels of total free amino acids. Therefore, based on protein degradation characteristics, large ‘Daewon’ soybeans and small ‘Wonkwang’ soybeans were the most suitable for producing cheonggukjang.     

Simultaneous determination of macrolide residues in fish and shrimp by liquid chromatography-tandem mass spectrometry

A sensitive and selective analytical method for 7 macrolides determination by LC-tandem mass spectrometry (LC-MS/MS) in fish and shrimp was developed. Samples were extracted by liquid-liquid extraction steps using 70% acetonitrile. The positive ionization produced the molecular related ions, (M+2H)²⁺, at m/z 422.3 for spiramycin I, and (M+H)⁺, at m/z 734.5, 772.4, 828.4, 837.4, 916.5, and 814.4 for erythromycin A, kitasamycin, josamycin, roxithromycin, tylosin A, and oleandomycin, respectively, were the precursor ions for collision-induced dissociation (CID) and 2 diagnostic product ions for each analyte were identified to carry out selected reaction monitoring (SRM) LC-MS/MS analyses. The recovery rates of macrolides in fish and shrimp samples were in the range 68.2–89.0, 72.8–91.6% and 75.2–87.0, 64.4–83.2% for the concentration of 50 and 100 ng/g, respectively.     

Biological activities of cheonggukjang prepared with several soybean cultivars

To select proper soybean cultivars for producing functional cheonggukjang, a comparison was made of the physiological activities of different cheonggukjang prepared with 30 different soybean cultivars. The isoflavone content was highest in the cheonggukjang made from ‘Daepung’ soybeans at 208.75 mg%. In general, the contents of glycone types (and derivatives) of isoflavone, specifically daidzin, glycitin, genistin, and malonylgenistin, were higher than that of aglycone types. The polyphenol contents ranged from 30.62 to 80.32 mg%. The DPPH radical scavenging activity and superoxide dismutase (SOD)-like activity of the cheonggukjang made from yellow soybeans had a higher activity than those of black soybeans. Although there are no consistent tendencies in the functional activity of cheonggukjang according to soybean color and size, the antioxidative activity is highest in the cheonggukjang made of yellow soybeans. Additionally, the fibrinolytic and inhibitory activities against angiotensin I-converting enzyme are highest in the cheonggukjang made of black soybeans. From these results, it can be concluded that the DPPH free radical scavenging activity and SOD-like activity in cheonggukjang depends on the phenolic compound content in soybean.     

Determination of biogenic amines in Japanese miso products

Eight miso products sold in supermarket were purchased from Japan and analyzed for the determination of biogenic amines (BAs). Quantitative determination of BAs in miso products was carried out by means of HPLC with spectrophotometric UV-VIS detector. The amines were extracted in acid aqueous solution (HClO₄) and then derivatized by dansyl chloride. The levels of pH in the tested miso samples were ranged from 4.8–5.5. The BAs (tryptamine, 2-phenyl ethylamine, putrescine, cadaverine, agmatine, tyramine, and spermidine) determined in 8 miso samples were found in their respective range of ND-0.13, ND-4.20, ND-1.29, ND-0.87, ND-0.90, ND-4.19, and ND-3.57 mg%. None of the miso samples contained histamine and spermine, the major BAs of food poisoning.     

Improved menaquinone (Vitamin K2) production in cheonggukjang by optimization of the fermentation conditions

To improve the content of menaquinone (MK) in cheonggukjang by using Bacillus amyloliquefaciens KCTC11712BP, the fermentation conditions were optimized. The rate of sporulation was found inversely correlated with MK productivity in soybean extract medium during the fermentation process. The best sensory quality of cheonggukjang was appeared at 36 h of fermentation. The synthesis rate of MK was slowed down after fermented for 36 h, which may due to the accumulation of aromatic amino acids (phenylalanine, tyrosine, and tryptophan). Especially, tryptophan was found to be the most sensitive feedback inhibitor of MK biosynthetic pathway. The optimum temperature for MK production was 43°C, and supplement of 4% glycerol could significantly increase the yield of MK. The content of MK in cheonggukjang fermented by using B. amyloliquefaciens KCTC11712BP under the optimum condition reached as high as 12.47 μg/g, which was about 4-fold higher than that of commercial cheonggukjang and natto products.     

On-line Solid-Phase Extraction Coupled to Liquid Chromatography–Ion Trap Tandem Mass Spectrometry for Determination of Penicillins in Catfish

A highly selective method was developed for the simultaneous determination of eight penicillins in catfish using automated on-line solid-phase extraction coupled to liquid chromatography–tandem mass spectrometry (XLC–MS/MS). The type of cartridge, equilibration sample volume, volume of solvent to carry the sample into the cartridge, and elution times were studied in order to optimize the XLC operating conditions. MS/MS conditions were also adjusted for better peak resolution. The present method was validated in agreement with the criteria of Commission Decision 2002/657/EC, showing a linear range from 2 to 350 μg kg⁻¹ and regression coefficient higher than 0.995 for the studied penicillins. Decision limits, calculated in the case of substances with no permitted limit, were lower than 0.6 μg kg⁻¹, and detection capability values were lower than 2.0 μg kg⁻¹. Samples spiked at 2.0, 10.0, and 50.0 μg kg⁻¹ showed high recovery (72–92%) and precision values lower than 20% except for amoxicillin. The present method was also applied for the analysis of penicillins in 30 catfish samples bought in local markets.     

HPLC-MS/MS analysis of 9 artificial sweeteners in imported foods

An analytical method for the simultaneous determination of 9 artificial sweeteners (acesulfame-K, cyclamate, sodium saccharin, aspartame, alitame, neotame, sucralose, dulcin, and neohesperidine dihydrochalcone) in imported foods by HPLC-MS/MS was developed. Samples were extracted with buffer solution (pH 4.5). The supernatant was analyzed by HPLC-MS/MS after centrifugation and filtration. The sample was separated on a thermo hypersil BPS C₁₈ (250×3 mm, 5-μm) column, and detected by MS/MS with selective reaction monitoring (SRM) mode. The correlation coefficients (r ²) of the calibration curve were >0.99. The recoveries were 90.0–107.5% with good coefficients of variation of 1.8–8.6%. The limits of detection and limits of quantification were between 0.001 and 0.375 mg/mL and between 0.003 and 1.125 mg/mL, respectively. The proposed method has been successfully applied to the determination of the 9 sweeteners in various foods.

     

Identification of antioxidative oligopeptides derived from autolysis hydrolysates of sea cucumber (<Emphasis Type="Italic">Stichopus japonicus</Emphasis>) guts

Oligopeptides were prepared from the guts of sea cucumber Stichopus japonicus by autolysis method. Optimum autolysis conditions for preparing oligopeptides from the guts of sea cucumber were determined by response surface methodology using a central composite rotatable design. The effects of two independent variables, namely temperature and pH, on the response of trichloroacetic acid-soluble oligopeptides (mg/g on dry basis) were investigated. Regression analysis indicated that more than 95 % of the variation could be explained by the fitted models. Temperature at 48.30 °C and pH at 4.43 were found to be the optimal conditions to obtain oligopeptides from the guts of sea cucumber. The autolysis hydrolysates prepared at the optimized conditions were further fractionated into four major fractions (I–IV) by size exclusion chromatography on a Sephadex G-15 column. Fraction IV, which exhibited the highest DPPH radical scavenging capacity, Fe²⁺-chelating ability and protective effect against hydroxyl radical-induced DNA damage, was then analyzed by ESI–MS for molecular mass determination and ESI–MS/MS for the characterization of peptides. Two tetrapeptides (Val-Thr-Pro-Tyr and Val-Leu-Leu-Tyr) and a hexapeptide (Val-Gly-Thr-Val-Glu-Met) were found to exhibit protective effects against hydroxyl radical-induced DNA damage. These results suggest that antioxidant oligopeptides derived from the guts of sea cucumber by autolysis method could be utilized for functional foods.     

Citrinin Determination in Red Fermented Rice Products by Optimized Extraction Method Coupled to Liquid Chromatography Tandem Mass Spectrometry (LC‐MS/MS)

A rapid and sensitive method was developed and validated for citrinin determination in red fermented rice products by liquid chromatography tandem mass spectrometry (LC‐MS/MS) under the selected reaction monitoring mode. Sample preparation was especially focused, and the quantitative methods of LC‐MS/MS and high‐performance liquid chromatography with fluorescence detection (HPLC‐FLD) were compared. In red fermented rice samples, the limit of detection was 1.0 μg/kg for LC‐MS/MS compared to 250 μg/kg for HPLC‐FLD, the limit of quantification was 3.0 μg/kg for LC‐MS/MS compared to 825 μg/kg for HPLC‐FLD. High correlation coefficient was obtained (R² = 0.999) within the linear range (0.1 to 100 μg/L) in the MS method. The recoveries ranging from 80.9% to 106.5% were obtained in different spiking concentrations. The average intra‐ and inter‐day accuracy ranged from 75.4% to 103.1%, and the intra‐ and inter‐day precisions were from 3.3% to 7.9%. The developed method was applied to 12 commercial red fermented rice products, and citrinin was found in 10 samples ranging from 0.14 to 44.24 mg/kg. Compared to traditional qualitative and quantitative methods, the newly developed LC‐MS/MS method for citrinin determination includes the merits of using a small amount of extraction solvent, simple preparation steps, and high sensitivity.     

Migration of ε-caprolactam from nylon cooking utensils: validation of a liquid chromatography-ultraviolet detection method

A large amount of modern cooking utensils are made of nylon. This is the generic name of polyamides that are polymers having characteristic amide linkages. Caprolactam is the monomer used in the synthesis of nylon 6. This work presents the validation of an LC-UV method for the determination of caprolactam in the aqueous food simulant 3% acetic acid (w/v) employing capryllactam as internal standard. LC–MS/MS was the confirmation technique. The obtained detection and quantification limits were satisfactory regarding caprolactam specific migration limit; these were 0.6 and 2 mg kg⁻¹, respectively. The working range was 2–30 mg kg⁻¹ and the correlation coefficients (r) were in all cases at least 0.999. The intra-day repeatability was between 2.5 and 4.8% depending on the validation level. The global mean recovery was 100.6% with a RSD (%) of 5.0%. Different nylon cooking utensils were analyzed for the migration of caprolactam in the food simulant acetic acid 3% p/v. Conditions used were repeated exposure to the simulant for 2 h at 100 °C, and the results obtained after the third exposure were in compliance regarding Directive 2002/72/EC. With the aim of identifying the polymer used in these utensils, IR spectra were also obtained for all samples.     

Characteristics of Cheonggukjang produced by the rotative fermentation method

This study was to develop a processing method for improving the quality of a fermented soybean food, cheonggukjang. Bacillus sp. AS-2 isolated from traditionally fermented cheonggukjang was selected for the production of cheonggukjang with the rotative fermentation method (RFM). The pH value of cheonggukjang made by RFM (cRFM) was 6.1±0.25. The amount of crude protein (329.0±0.92 mg/g) and amino-type nitrogen (120.6±21.81 mg%) were similar to those in traditionally fermented cheonggukjang (cTFM). The amount of ammonium-type nitrogen was 173.0±1.72 mM/g and nearly 4 times lower than that in cTFM. 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical scavenging values in the traditional product were between 1.62±0.08 and 1.27±0.05, while with the RFM, the values were between 1.38±0.02 and 0.78±0.20. The antioxidative activity of the sauce-type cRFM was approximately 1.7 times higher than that of cTFM. The sensory scores for cRFM were uniformly higher than those for cTFM.     

Antioxidant activities of the rice endosperm protein hydrolysate: identification of the active peptide

The defatted rice endosperm protein (REP) was digested using five different proteases (Alcalase, Chymotrypsin, Neutrase, Papain, and Flavorase) to produce the antioxidative peptide. The degree of hydrolysis of REP by Neutrase (20.00%) was slightly lower than that of Chymotrypsin, but higher than those of other enzymes. The Neutrase hydrolysate from rice endosperm protein (NHREP) took on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity similar to α-tocopherol. Also, the reaction condition of Neutrase hydrolysis was moderate (pH of 7.0 and temperature of 37 °C). Therefore, Neutrase was chosen to be the optimum enzyme for producing the antioxidative peptide from REP. In succession, the antioxidant activities of NHREP were further evaluated. The median effective concentration (EC₅₀) value of NHREP for hydroxyl radical scavenging activity was 2.0 mg/mL, while its superoxide radical scavenging activity did not surpassed 50% even at 6 mg/mL. The percentage inhibition of autooxidation in linoleic acid system by NHREP was 82.09%, similar to that of α-tocopherol (86.59%) on day 5 at the same concentration. NHREP displayed 89.15% chelating effect on ferrous ion at a concentration of 1000 μg/mL, and a high correlation was also observed between the reducing power and antioxidant activity of NHREP (r ² = 0.99678). Consequently, NHREP was purified and identified, and the sequence determination by MALDI-TOF/TOF MS/MS revealed that the active constituent contained eight amino acids in its sequence (Lys-His-Asn-Arg-Gly-Asp-Glu-Phe), with the molecular mass of 1002.5217 Da. After sequence interpretation and database searching, the MS/MS spectrum was matched to glutelin protein f (460–465).     

Impact of UV‐C Light on the Fatty Acid Profile and Oxidative Stability of Nile Tilapia (Oreochromis niloticus) Fillets

The influence of different ultraviolet (UV‐C) doses (0.103 and 0.305 J/cm²) was investigated by instrumental color parameters, pH, lipid, and protein oxidations, fatty acids (FA) composition and biogenic amines (BAs) in Nile tilapia fillets during 11 d at 4 ± 1 °C. The UV‐C treatment increased (P < 0.05) a^* values and protein oxidation in a dose‐dependent manner, and delayed (P < 0.05) the formation of BAs over the course of the storage period. L^* values and lipid oxidation were not influenced (P > 0.05) by UV‐C light. Fillets treated with a low UV‐C dose exhibited greater (P < 0.05) total polyunsaturated fatty acid (PUFA) than their untreated counterparts. Therefore, a low UV‐C dose can be recommended in tilapia fillets as an alternative processing method to control pH and BAs, as well as improve the total PUFA amount and overall nutritional quality.     

Rapid Analysis of Flavor Volatiles in Apple Wine Using Headspace Solid‐Phase Microextraction

Flavor volatiles are important components of alcoholic beverages. In this study, headspace solid‐phase microextraction and gas chromatography—mass spectrometry (HS‐SPME‐GC‐MS) were investigated for the determination of flavor‐contributing volatiles for apple wine. HS‐SPME parameters were defined, including fiber coatings, extraction time, and extraction temperature. Good linearity, recoveries, and repeatability of the SPME method using carboxen‐polydimethylsiloxane (carboxen‐PDMS) fiber were obtained with r² values, recoveries, and relative standard deviations ranging from 0.9112 to 0.9960, 80.23% to 110.21%, and 1.5% to 6.4% respectively using standard solution. No significant effects of ethanol concentration on headspace concentrations of analytes were observed when ethanol concentration changed from 0% to 12% (v/v), indicating that the HS‐SPME‐GC‐MS method can be used for the determination of flavor volatiles in apple wine with an alcohol content below 12% (v/v) as well as in apple juice, and the method enables the monitoring of volatiles in mash during fermentation.     

Simultaneous determination of 10 mycotoxins in grain by ultra-high-performance liquid chromatography–tandem mass spectrometry using 13C15-deoxynivalenol as internal standard

An ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS) method for simultaneous determination of 10 mycotoxins in grain was developed. The selected mycotoxins were: deoxynivalenol, 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol, nivalenol, fusarenon X, moniliformin, zearalenone, zearalanone, ochratoxin A and ochratoxin B. The samples were extracted with aqueous acetonitrile (84?:?16,?v/v) and purified by reliable laboratory-made mixed cartridges. The analytes were separated on an Acquity UPLC HSS T3 column (100?×?2.1?mm,?1.8?µm) and eluted with a mobile phase of water containing 0.2% aqueous ammonia and acetonitrile/methanol (90?:?10,?v/v). All mycotoxins were detected with a Waters Micromass Quattro Ultima Pt tandem quadrupole mass spectrometer operating in negative electrospray ionization using multiple reaction monitoring mode. Accurate determination was achieved by employing commercial ¹³C₁₅-deoxynivalenol as internal standard, which compensated for target loss and eliminated matrix effects. The established method was further validated by determining the linearity (R ^2?>?0.9990), average recovery (75.8–106.5%), sensitivity (limit of quantitation 0.09–8.48?µg?kg^?1) and precision (relative standard deviation?≤?6.9%). It was shown to be a suitable method for simultaneous determination of 10 mycotoxins in grain. Finally, a total of 69 corn samples randomly collected from eastern and northern China were analyzed. The results showed that deoxynivalenol was the most frequently detected contaminant, whilst 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol, nivalenol, zearalenone, zearalanone, fusarenon X and moniliformin also occurred frequently. Ochratoxin A and ochratoxin B were present only in trace amounts in a small number of samples.     

Ultrasonically Assisted Extraction of Rutin from <Emphasis Type="Italic">Artemisia selengensis</Emphasis> Turcz: Comparison with Conventional Extraction Techniques

Ultrasonically assisted extraction (UAE) followed by high performance liquid chromatography (HPLC) analysis method for the fast extraction and determination of rutin in Artemisia selengensis Turcz has been developed. Artemisia selengensis Turcz has been used as food and herbal medicine for thousands of years in China. Rutin is one of the main active ingredients of this plant. The extraction of rutin from Artemisia selengensis Turcz was investigated by UAE. Special emphasis has been given to optimize the extraction conditions which were those with 90:10 (v/v) methanol–ethanol as solvent, 30:1 liquid–solid ratio, and 40 min extraction time. In order to show the superiority of UAE, other extractions were investigated, including microwave-assisted extraction, reflux extraction, and marinated extraction. The results showed that UAE was most suitable for the extraction of rutin in Artemisia selengensis Turcz because of its high extraction efficiency. Reversed phase-HPLC with ultraviolet detection was employed for the analysis of rutin in Artemisia selengensis Turcz. Under the optimum conditions, the calibration curve for the analyte was linear in the range of 0.34–20.7 μg mL⁻¹. The mean recovery of rutin was 100.77%, and its relative standard deviation was 0.37% (n = 5). Three kinds of Artemisia selengensis Turcz from different habitats were investigated. The total content of rutin was 9.90, 6.23, 5.56 mg g⁻¹, respectively.     

Determination of Pesticide Residues in Golden Berry (<Emphasis Type="Italic">Physalis peruviana</Emphasis> L<Emphasis Type="Italic">.</Emphasis>) by Modified QuEChERS Method and Ultra-High Performance Liquid Chromatography-Tandem Quadrupole Mass Spectrometry

A fast and effective multiresidue method for the determination of 42 pesticides in golden berry was developed and validated. A modified QuEChERS method was established for sample preparation followed by ultra-high performance liquid chromatographic-tandem mass spectrometry (UHPLC-MS/MS) determination with electrospray ionization in a triple quadrupole system. Validation results were satisfactory, since the method presented recoveries between 70 and 114 % with relative standard deviations (RSD) <20 % for blank samples spiked from 5 to 25 μg kg^?1. The method limit of detection and limit of quantification were 1.5 and 5 μg kg^?1 _, respectively. Matrix effect ranged from ?32 to 218 % and was compensated using matrix-matched calibration. Method linearity was established from 2.5 to 100 μg kg^?1 with r ² ≥ 0.99. The proposed method combines the advantages of a simple and fast sample preparation step by a modified QuEChERS method with the high selectivity and sensitivity of the UHPLC-MS/MS system using selected reaction monitoring. The method was successfully applied to commercial samples, proving to be an efficient alternative for routine analysis. From the 16 analyzed samples, 13 presented residues of one or more pesticides (carbendazim, chlorpyrifos ethyl, dimethoate, propamocarb, and tebuconazole) in the concentration range of 2.0 to 55.6 μg kg^?1.     

Development and validation of a solid-phase extraction method coupled with HPLC-UV detection for the determination of biogenic amines in Chinese rice wine

ABSTRACT

A reliable and accurate method for the determination of seven biogenic amines (BAs) was developed and validated with Chinese rice wine samples. The BAs were derivatised with dansyl chloride, cleaned up using solid-phase extraction (SPE) and separated by high-performance liquid chromatography (HPLC) coupled with ultraviolet (UV) detection. The optimised derivatisation reaction, conducted at pH 9.6 and 60°C for 30 min, ensured baseline separation and peak symmetry for each BA. SPE clean-up using Oasis MCX cartridges yielded good recovery rates for all BAs and effectively reduced matrix effects. The developed method shows good linearity with determination coefficients of more than 0.9989 over a concentration range of 0.1–100 mg l^?1. The limits of detection (LODs) for the investigated BAs ranged from 2.07 to 5.56 µg l^?1. The intra- and inter-day relative standard deviations (RSDs) ranged from 0.86% to 3.81% and from 2.13% to 3.82%, respectively. Spiking experiments showed that the overall recovery rates ranged from 85% to 113%. Thus, the proposed method was demonstrated as being suitable for simultaneous detection, with accurate and precise quantification, of BAs in Chinese rice wine.     

Quantitative Determination and Confirmation of Five Synthetic Glucocorticoid Residues in Milk Powder by Gel Permeation Chromatography–Liquid Chromatography–Tandem Mass Spectrometry

A new method for multi-residue determination of five synthetic glucocorticoids (betamethasone, dexamethasone, prednisone, prednisolone, and hydrocortisone) in milk powder is developed. The glucocorticoids in the samples were extracted with tert-butyl methyl ether under ultrasonication incubation, and then cleaned up through gel permeation chromatography. After C18 LC gradient elution separation using acetonitrile with 0.1% formic acid as a mobile phase, the eluents were determined by liquid chromatography–tandem mass spectrometry with multiple reaction monitoring and positive ionization modes. The effective separation for the five glucocorticoids was achieved. The limit of quantification of the method for testing five glucocorticoids in milk powder was in the range from 0.2 to 0.5 μg kg⁻¹, which was lower than the maximum residue limits established by European Union for glucocorticoids in foods. Experiments on spiked samples of milk powder showed that the mean recoveries at addition level of 1.0, 3.0, and 5.0 μg kg⁻¹ were in the range of 71.2% and 103%, and the relative standard deviation ranged from 4.7% to 16.8%. The calibration curves for these drugs between 1.0 and 100 μg l⁻¹ showed good linearity, with correlation coefficient (r) more than 0.999. The real sample test showed that this method is sensitive and accurate. It can be used for qualitative and quantitative determination of studied glucocorticoid residues in milk powder samples.     

Total Mercury, Inorganic Mercury and Methyl Mercury Determination in Red Wine

This study deals with the development of a method for total Hg, inorganic Hg and methylmercury (MeHg) determination in red wine by using flow injection-cold vapour generation–inductively coupled plasma mass spectrometry (FI-CVG-ICP-MS) and gas chromatography-ICP-MS (GC-ICP-MS). For Hg speciation analysis, a derivatization step was carried out using a 1% (m/v) sodium tetraphenylborate (NaBPh₄) solution, followed by extraction of Hg species and their quantification by GC-ICP-MS. The main parameters evaluated were the make-up gas flow rate, volume of the NaBPh₄ solution, time for derivatization reaction/analyte extraction and solvent used for Hg species extraction. Accuracy was evaluated by analyte recovery, whereas recoveries ranged from 99% to 104% for Hg(II) and MeHg. The limits of detection (LODs) for Hg(II) and MeHg were 0.77 and 0.80 μg L⁻¹, respectively. Wine from Argentina, Brazil, Chile and Uruguay were analysed. The wine samples were also acid digested for total Hg determination by FI-CVG-ICP-MS. The LOD of the method used for total Hg determination was 0.01 μg L⁻¹. The concentrations of Hg species in red wine measured by GC-ICP-MS were lower than the respective LODs. Only total Hg was detected in the analysed samples, where the highest concentration of Hg found was 0.55 ± 0.02 μg L⁻¹.