Simultaneous determination of bisphenol A-diglycidyl ether, bisphenol F-diglycidyl ether and their hydrolysis and chlorohydroxy derivatives in canned foods

A new method for the simultaneous determination of bisphenol A-diglycidyl ether (BADGE), bisphenol F-diglycidyl ether (BFDGE) and their hydrolysis and chlorohydroxy derivatives in canned foods is presented. Oily and aqueous food samples were extracted with tert-butyl methyl ether and acetonitrile, respectively. The compounds in both extracts were determined by using reverse-phase gradient high-performance liquid chromatography with fluorescence detection. Optimization of extraction and chromatographic determination is outlined in detail. After validation the method was used to analyze various canned food samples, such as tuna and sardine in oil, vegetables, fruit cocktails, etc. In none of the samples were significant amounts ( >100 μg/kg) of BADGE or BFDGE found, whereas in most samples BADGE/BFDGE chlorohydroxy compounds were detected. These originate most probably from the use of organosol varnishes instead of epoxy resins. Risk assessment and regulations of these compounds by the European Union are urgently needed. Additionally, the syntheses and characterization of the not available standard compounds bisphenol A-p-glycidyl-p′-(3-chloro-2-hydroxypropyl) ether (BADGE.HCl) and bisphenol A-p-(2,3-dihydroxypropyl)-p′-(3-chloro-2-hydroxypropyl) ether (BADGE.HCl.H₂O) are presented. Received: 28 July 1999 / Revised version: 29 October 1999     

食品包装材料中有害物质双酚A二缩水甘油醚 体外代谢研究

目的通过模拟体内代谢,对双酚A二缩水甘油醚(BADGE)的体外基本代谢情况进行研究。方法采用肝微粒体、肝S9 2种体外代谢试剂,通过模拟体内肝脏代谢,对BADGE的代谢行为及其代谢产物进行研究。通过代谢试剂浓度及代谢时间条件的优化,采用高效液相色谱-串联质谱(HPLC-MS/MS)作为检测手段对BADGE的体外代谢产物进行分析确证。结果体外代谢最佳孵化时间为60 min,最佳体外代谢试剂浓度为0.5mg/m L,在肝S9及肝微粒体2种体外代谢试剂的作用下,BADGE发生显著的代谢反应。结论本研究与传统的动物试验相比,节约了时间、精力,对食品包装材料的毒理学研究和安全性评价有重要的推动作用。     

Bisphenol A diglycidyl ether (BADGE) migrating from packaging material ‘disappears’ in food: reaction with food components

Bisphenol A diglycidyl ether (BADGE) is widely used as a monomer for coatings and adhesives for food-contact applications. Previous publications indicate that, after migration from packaging into foodstuffs, BADGE undergoes various reactions with unidentified food components. In order to elucidate the fate of BADGE, losses were determined after incubation with different foodstuffs and food components. Food proteins were identified as the main reaction partner with BADGE. Adduct formation was found with nucleophilic side-chains of amino acids. In vitro, cysteine exhibited significant activity. The previously reported occurrence of methylthio-derivatives of BADGE in foodstuffs was shown to originate from the reaction of BADGE with methionine. BADGE-methylthio derivatives can, therefore, be used as marker substances in foodstuffs for protein reactions with BADGE. The reported results offer a new viewpoint on the evaluation of BADGE migration. The hydrolysis and hydrochlorination derivatives subject to European legislation make up only a fraction of the totally migrated BADGE, and a further concern is that the toxic or allergenic potential of the protein adducts are unknown.     

Bioassay Guided Analysis of Migrants from Can Coatings

Migrants from can coatings consist of a complex mixture of a variety of substances that mostly are not toxicologically evaluated. 95% ethanolic migrates from a polyester and an epoxy coating were screened in different bioassays on mutagenicity (Ames II-Test), on aquatic toxicity (Fish Embryo Assay) and on cytotoxicity (BrdU-ELISA, WST-1-Assay, Neutral Red Assay (NRA), RNA-Synthesis-Inhibition). No mutagenic effect was detected in the Ames II-Test and no lethal effects were induced in the fish embryo test up to a concentration of 60 dm²/l. Strongly varying cytotoxicity effects have been determined depending on the type of the assay, the cell line in use (Hela-S3, Caco-2, HT-29, Hep-G2) as well as the incubation conditions. The NRA was validated for the investigation of the coating migrates. Legally regulated substances known to migrate from epoxy coatings, BPA, BADGE, BADGE*2H₂O, BADGE*HCl*H₂O and BADGE*2HCl were investigated in the NRA with two different cell lines, a human colon adenocarcinoma cell line (HT-29) and a human hepatocellar carcinoma cell line (Hep-G2). The IC_{50, Hep-G2}-values of the regulated epoxy based substances ranged from 7 mg/l for BADGE to 83 mg/l for BADGE*2H₂O. The 95% ethanolic migrate of the epoxy coating revealed a significant effect in the NRA (IC_{50, Hep-G2} =  6.6 ±  0.8 dm²/l) while the polyester coating induced no effect (IC_{50, Hep-G2}  >  30 dm²/l). The amount of the legally regulated substances (BPA, BADGE, BADGE*2H₂O) in the migrate of the epoxy coating was analysed and their part on the cytotoxic effect of the migrate was estimated. Only about 0.5% of the effect of the migrate in the NRA could be traced back to these substances.     

Application of Response Surface Methodology to Improve Carotene Production from Synthetic Medium by <Emphasis Type="Italic">Blakeslea trispora</Emphasis> in Submerged Fermentation

Optimization of the medium components which enhance carotene production by Blakeslea trispora was achieved with the aid of response surface methodology. In the first step, a central composite design was employed to achieve the highest carotene concentration at optimum values of the process variables, i.e., linoleic acid, Span 20, and butylated hydroxytoluene (BHT), added in the basal medium. The fit of the model was found to be significant. The production medium to achieve the highest carotene concentration (139.0 ± 4.5 mg/g dry biomass) was composed of the basal medium supplemented with linoleic acid (21.3 g/l), Span 20 (16.0 g/l), and BHT (4.7 g/l). The results show that the optimization strategy led to an increase in carotene production by 35-fold. The carotenes content in Β. trispora were β-carotene (45%), γ-carotene (31%), and lycopene (24%). In the second optimization step, the production medium was supplemented with different trace elements which significantly affect carotene production (i.e., CuSO₄^.5H₂O, FeCl₃^.6H₂O, and Co(NO₃)₂.6H₂O). The experimental validation showed that the model was effective. The optimized medium for enhanced carotene concentration consists of the production medium supplemented with 395.64 mg/l CuSO₄^.5H₂O, 10.0 mg/l FeCl₃^.6H₂O, and 1.12 mg/l Co(NO₃)₂^.6H₂O. Practical validation of the above optimum medium gave carotene production 154.0 ± 5.0 mg/g dry biomass, which is 10% higher than the concentration of carotenes in the production medium. In this case, the carotenes consisted of β-carotene (37%), γ-carotene (47%), and lycopene (16%). Thus, the addition of trace elements to the production medium increased slightly the concentration of carotenes, but changed mainly the composition of the carotenes to a drastic increase of γ-carotene concentration.     

Studies on rats fed a dietary fibre preparation from sugar beet

 Groups of 15 female rats were fed ad libitum for 4 weeks with a standard diet containing 0, 2.5, 5 or 10% of a dietary fibre (DF) preparation made on a laboratory scale from sugar beet pulp. This preparation had a total DF content of 72.2%. Its major components were 36.7% cellulose, 16.9% pectin, 16.8% hemicelluloses (HC) and 11.0% protein. The DF preparation from sugar beet exhibited a water-binding capacity (WBC) of 8.9 g H₂O/g. As the proportion of DF preparation in the diet increased, up to 15.8% total DF, 4.6% cellulose and 1.9% pectin were found in the feeds. The WBC of the diets was estimated to be 1.4–2.9 g H₂O/g. At the end of the experiment, 20.3–64.1% total DF, 10.3–38.2% cellulose, 0.2–7.8% pectin, 4.3–9.2% HC pentoses and 4.3–10.3% HC hexoses were determined in caecum contents (ca. 0.6 g dry weight/rat). The following proportions were found in faeces (3rd week; 1.4–1.9 g dry weight/rat): 34.5–56.9% total DF, 19.5–36.1% cellulose, 6.4–8.4% HC pentoses, 7.4–8.3% HC hexoses. The WBC of faeces ranged from 3.7 g H₂O/g to 4.9 g H₂O/g. About 30–50% of the daily intake of DF appeared in the faeces. Higher amounts of total DF, pectin and HC pentoses were fermented by gastrointestinal microflora as the concentration of DF preparation from sugar beet in the diet increased. In addition, the fermentation of different DF components could be shown by the monosaccharide composition of caecum contents and faeces. Received: 21 October 1997     

国内市场上罐装啤酒中双酚类物质迁出量调查

建立并利用固相萃取-高效液相-荧光法对国内市场上31种罐装啤酒中双酚物的含量进行了调查。方法的检测限为0.02～0.09μg/L,在0.02～50.00μg/L的检测范围内相关系数大于0.99,加标回收率和标准差分别为80.67%～101%和1.01%～4.84%。样品中除双酚E(BPE)没有检出外,双酚A(BPA)、双酚A二缩水甘油醚(BADGE)、双酚F二缩水甘油醚(BFDGE)、双酚B(BPB)和双酚F(BPF)的平均检出浓度分别为2.99、0.41、0.18、0.12、0.12μg/L,检出率分别为100%、83.9%、6.4%、12.9%和6.4%。BPA和BADGE是罐装啤酒中存在的最主要的双酚物,其平均每日摄入量分别估计为0.0160、0.0022μg/kg.bw.d,低于欧盟关于BPA50μg/kg.bw.d的规定。样品中BPA没有超过欧盟规定的0.6mg/L,BADGE的迁移也未高于9mg/L,但是BFDGE的检出是不允许的。目前尚无关于BPF、BPE和BPB的迁移限值。     

Survey of bisphenol a diglycidyl ether (BADGE) in canned foods.

2,2-Bis(4-hydroxyphenyl)propane bis(2,3-epoxypropyl) ether (BADGE) is used in the manufacture of lacquers for coating the inside of food and beverage cans. In June 1996 the EC Scientific Committee for Food temporarily increased the specific migration limit applying to BADGE to 1 mg/kg pending consideration of additional toxicological data. In order to find out if there is migration of BADGE from can coatings into foods, a 'worst case' sampling exercise has been conducted to survey those canned foods where the propensity for migration of BADGE was judged to be highest. The foods surveyed include canned fish in oil, meat and milk and, altogether, BADGE was determined in 181 retail samples. Analysis for BADGE was conducted, in duplicate, by HPLC with fluorescence detection with confirmation of BADGE identity by GC/MS analysis using selected ion monitoring. BADGE was found at levels exceeding 1 mg/kg in seven of the 15 canned anchovy samples and five of the 22 sardine samples purchased during the period September 1995-July 1996. Infrared analysis of the can coatings provided strong evidence that the higher BADGE levels found were associated with use of PVC organosol lacquers, although in some cases cans coated with organosols gave low BADGE results. For canned sardine samples found to contain greater than 0.5 mg/kg BADGE in the total contents, a replicate can was opened and separate analyses performed on the drained fish and the oil. The results clearly showed that BADGE concentrations in the oil were about 20 times higher than in the drained fish. Further samples of canned sardines and anchovies were purchased in June/July 1997 and, in all cases, BADGE levels were found to be below 1 mg/kg. In the other retail canned foods, BADGE was not detectable (DL = 0.02 mg/kg) or detected at concentrations well below the temporary SML of 1 mg/kg.     

Migration of bisphenol-A diglycidyl ether (BADGE) and its reaction products in canned foods

Bisphenol-A diglycidyl ether (BADGE) is used as an additive or starting agent in coatings for cans. The presence of hydrochloric acid in the organosol (PVC-based) lacquers results in formation of chlorohydroxy compounds of BADGE. These compounds, as well as BADGE itself, are potential migrants into the preserved food and are of toxicological concern. In the present investigation the presence of BADGE and the chlorohydroxy compounds (BADGE.HCl and BADGE.2HCl) in various kinds of canned foods from 30 brands have been determined by HPLC with fluorescence detection. BADGE was found in levels up to 5.1mg/kg in the food and only in food from cans containing BADGE.HCl and BADGE.2HCl in the lacquers. BADGE was found both in fish in oil and in fish in tomato sauce, however, the highest amounts were found in the fatty foodstuffs. BADGE.HCl and BADGE.2HCl were found in concentrations up to 2.4mg/kg and 8.3mg/kg, respectively. Unlike BADGE, BADGE.2HCl was found in similar concentrations in fish in oil and in fish in tomato sauce. In aqueous and acidic foodstuffs BADGE readily hydrolyses into mono- and dihydrolysed products (BADGE.H₂O and BADGE.2H₂O). In this study BADGE.H₂O was not found in any food sample, whereas BADGE.2H₂O was found in levels up to 2.6mg/kg. The Scientific Committee for Food (SCF) of the European Commission has proposed that a limit of restriction of 1mg/kg food shall include BADGE itself and BADGE.H₂O, BADGE.HCl, BADGE.2HCl and BADGE.HCL.H₂O. The present results indicate that the migration of BADGE.HCl and BADGE.2HCl, compounds with almost no data on toxicity, implies a greater problem than BADGE.H₂O and BADGE.2H₂O.     

Determination of bisphenol A diglycidyl ether (BADGE) and its derivatives in food: identification and quantification by internal standard

Bisphenol A diglycidyl ether (BADGE) and its reaction products with water and hydrochloric acid have recently been subject to new regulations concerning their migration from food packaging into foodstuff. A method for the simultaneous identification and quantification of these substances and their precursor bisphenol A in food is described introducing bisphenol A di-(3-hydroxypropyl)ether as an internal standard. Analysis was carried out using RP-HPLC gradient elution with fluorescence detection. Additional information in the case of suspect samples was obtained using RP-HPLC with mass selective detection. The described method is validated for the analysis of foodstuffs as well as fatty food simulants. The limits of detection were between 10 and 30 µg/kg of food; recovery experiments gave identical behaviour for all analytes and the internal standard. The enforcement of the specific migration limit set by regulatory standards of the European Union for BADGE and its hydrolysis and hydrochlorination products is possible for producers as well as food quality surveillance institutions.     

Effect of microwave heating on the migration of dioctyl adipate and acetyltributyl citrate plasticizers from food grade PVC and PVDC/PVC films into ground meat

 Migration of dioctyl adipate (DOA) and acetyltributyl citrate (ATBC) plasticizers from plasticized poly(vinyl chloride) and poly(vinylidene chloride/vinyl chloride) films into ground meat of varying fat content (3%, 12%, 30%, 55%) during microwave heating has been studied. The plasticizer migrating into ground meat was determined using an indirect gas chromatographic method after saponification of the ester-type plasticizer (DOA or ATBC) and subsequent collection of the alcohol component of the ester, namely 2-ethyl-1-hexanol and 1-butanol, respectively. Identical unwrapped microwave heated (control) samples were also analysed for DOA and ATBC content. Migration was dependent on heating time, fat content of the meat and the initial concentration of the plasticizer in the film. Migration of DOA and ATBC into ground meat did not reach equilibrium after heating for 4 min at full power even for meat samples of high fat content (55%). Migration values of DOA and ATBC into ground meat of 55% fat content after 4 min of heating in a microwave oven were 172.39 mg/kg (14.62 mg/dm²) and 17.24 mg/kg (0.62 mg/dm²), respectively. Migration into control samples was below the detection limit of the method employed (<2 mg/kg for DOA and <2.5 mg/kg for ATBC). Received: 23 February 1998     

Effect of microwave heating on the migration of dioctyl adipate and acetyltributyl citrate plasticizers from food grade PVC and PVDC/PVC films into ground meat

 Migration of dioctyl adipate (DOA) and acetyltributyl citrate (ATBC) plasticizers from plasticized poly(vinyl chloride) and poly(vinylidene chloride/vinyl chloride) films into ground meat of varying fat content (3%, 12%, 30%, 55%) during microwave heating has been studied. The plasticizer migrating into ground meat was determined using an indirect gas chromatographic method after saponification of the ester-type plasticizer (DOA or ATBC) and subsequent collection of the alcohol component of the ester, namely 2-ethyl-1-hexanol and 1-butanol, respectively. Identical unwrapped microwave heated (control) samples were also analysed for DOA and ATBC content. Migration was dependent on heating time, fat content of the meat and the initial concentration of the plasticizer in the film. Migration of DOA and ATBC into ground meat did not reach equilibrium after heating for 4 min at full power even for meat samples of high fat content (55%). Migration values of DOA and ATBC into ground meat of 55% fat content after 4 min of heating in a microwave oven were 172.39 mg/kg (14.62 mg/dm²) and 17.24 mg/kg (0.62 mg/dm²), respectively. Migration into control samples was below the detection limit of the method employed (<2 mg/kg for DOA and <2.5 mg/kg for ATBC).     

Optimization of Conditions for Enzymatic Production of ACE Inhibitory Peptides from Collagen

Enzymatic condition for producing angiotensin I-converting enzyme (ACE) inhibitory peptides from collagen was optimized with the aid of response surface methodology, which also derived a statistical model for experimental validation. The results showed that the optimal condition for the hydrolysis by pepsin was at pH 2, temperature 37 °C, and in enzyme to substrate ratio (E/S) of 2 when 8.23% collagen (w/v) and 3.82 h of hydrolysis time were applied. Through the single-enzyme hydrolysis, the ACE inhibitory activity could reach an average of 78.06%. In contrast, when a combination of pepsin and trypsin was used for a multiple-proteases hydrolysis, the ACE inhibitory activity could be significantly improved to an average of 88.25%. Furthermore, the IC₅₀ (μg/mL) value of the enzyme combination by pepsin and trypsin (141.64 ± 22.11) was significantly lower than that of the combinations of pepsin and papain (438.59 ± 84.37) or pepsin and protease M (336.76 ± 87.88; p<0.05). Our results have shown that collagen can be used for enzyme-mediated production of ACE inhibitory peptides.     

Effect of the addition of nitrate to milk on the formation of volatile N-nitrosamines and apparent total N-nitroso compounds

 Saint-Paulin, a French semihard cheese, was manufactured from milk with and without added NO₃ ^–. Reference and experimental cheeses were analysed at different stages of ripening for the presence of apparent total N-nitroso compounds (ATNC) by chemical denitrosation and chemiluminescence detection (thermal energy analyser). The fate of NO₃ ^– and NO₂ ^–was also scrutinized. The levels of ATNC and of volatile N-nitrosamines were followed during ripening. After 60 days of ripening, ATNC were detected at concentrations of 27 μg NO-N/kg and 64 μg NO-N/kg in the cheeses obtained from milk with and without added NO₃ ^–, respectively. The NO₃ ^– contents of both cheeses were nearly the same, and below 5 mg/kg. The occurrence of NO₂ ^–was not observed. No relationship was found between the NO₃ ^– contents and the contamination of the cheeses by volatile N-nitrosamines. At the beginning of ripening, the cheeses manufactured with added NO₃ ^- showed high levels of ATNC (mean value 5800 μg N-NO/kg with large variations of 570–15210 μg NO-N/kg). These ATNC contents rapidly decreased during the first days of ripening (96%), but decreased much more slowly during the following days. An hypothetical mechanism, attempting to explain the disappearance of ATNC, involving the formation of alkylated species in the cheese was proposed. Received: 30 March 1998 / Revised version: 7 October 1998     

Bisphenol A (BPA) and its source in foods in Japanese markets

The determination of bisphenol A (BPA) and/or bisphenol A diglycidyl ether (BADGE) in foods sold in Japanese markets and in water leached from six epoxy resin cans with similar diameters was carried out using high-performance liquid chromatography (HPLC) with electrochemical detection (LC/ECD), LC-mass spectrometric detection (LC/MS) and LC-tandem mass spectrometric detection (LC/MS/MS). BPA concentrations were 0-842 ng g^-1 for 48 canned foods, 0-14 ng g^-1 for 23 foods in plastic containers, and 0-1 ng g^-1 for 16 foods in paper containers. No BADGE was detected in three canned foods. There was no difference in leaching concentrations of BPA into glycine buffers at pHs 8 and 11, and water. The amounts of BPA leached into water from six epoxy resin cans held at 121°C for 20 min were almost the same as the cans' contents and were much higher than the amounts leached from cans held at or below 80°C for 60 min. The amount leached depended on the type of can, but not on the amount of BADGE leached from the cans. Considerably more BPA than BADGE leached to water from six cans. Two cans whose contents had high concentrations of BPA showed no BADGE leaching even at 121°C, suggesting the different kinds of epoxy resin can linings from others. The results imply that the main source of human exposure to BPA is food from cans with linings that contain high percentages of BPA as an additive or an unforeseen contaminant.     

Simultaneous Determination of 69 Pesticide Residues in Coffee by Gas Chromatography?CMass Spectrometry

A method using gel permeation chromatography (GPC) combined with solid-phase extraction (SPE) cleanup followed by gas chromatography–mass spectrometry (GC-MS) has been established for quantitative determination of 69 pesticide residues in coffee. Based on an appraisal of the characteristics of GC-MS, validation experiments were conducted for 69 pesticides. In the method, 2.0 g samples were mixed with 5 ml water and 1 g sodium chloride and extracted with 5 ml of ethyl acetate by blender homogenization, centrifugation, and filtration. Evaporation was conducted and the sample was injected into a 250 mm × 10 mm S-X3 GPC column, with ethyl acetate–n-hexane (1:2 v/v) as the mobile phase at a flow rate of 3 ml/min. The 4–15 min fraction was collected for the SPE cleanup, which was Envi-Carb SPE cartridge coupled with NH₂-LC SPE cartridge with acetone–ethyl acetate (2:5 v/v) as the eluted solvent. The eluents were collected and then evaporated to dryness, which was redissolved in 0.5 ml ethyl acetate for GC-MS analysis. For the 69 pesticides determined by GC-MS, the portions collected from GPC were concentrated to 0.5 ml and exchanged with 5 ml n-hexane. In the linear range of each pesticide, the correlation coefficient was R ² ≥ 0.99. At the low, medium, and high fortification levels of 0.05–1.0 mg/kg, recoveries fell within 60–120%. The relative standard deviation was between 1.3% and 22.3% for all 69 pesticides. The limits of detection for the method were 10 μg/kg to 150 μg/kg, depending on each pesticide.     

Ellagic acid content in berries: Influence of domestic processing and storage

The content of ellagic acid was determined from the berries of the family Rosaceae (strawberry, red raspberry, cloudberry, arctic bramble). Extraction and hydrolysis procedures were optimized and analysis was done with an HPLC method and UV detection. The influence of processing on ellagic acid content was studied in strawberry jam. Strawberries, red raspberries, and strawberry jam were analyzed fresh and after 3, 6, and 9 months of storage in a domestic freezer or refrigerator. Ellagic acid contents after 3 months of storage at −20 °C varied between 31.5 (strawberry ‘Senga Sengana’) and 68.6 mg/100 g f.w. (arctic bramble). Ellagic acid content in strawberry jam (23.8 mg/100 g f.w.) was 80% of that in unprocessed strawberries. The content of ellagic acid in strawberries and red raspberries was reduced by 40% and 30%, respectively, during the 9 months of storage at −20°C. The unprocessed berries studied, together with nuts, make the main contribution to the total dietary intake of ellagic acid in Finland. Received: 7 December 1999 / Revised version: 22 February 2000     

Aflatoxins in nuts assayed by immunological methods

 Different kinds of raw and processed nuts available in the local retail market were investigated for aflatoxin content. Total aflatoxins and aflatoxin B₁ content were determined by immunoaffinity chromatography with fluorescence detection after reaction with bromine solution and by immunoenzymatic test kits. Of 29 investigated samples, 38% were contaminated. The total aflatoxin content in contaminated samples was between 1.20 μg/kg for peanuts and 5.50 μg/kg for walnuts. The concentration of aflatoxin B₁ found in contaminated samples was between 0.35 μg/kg for cashew nuts and 4.04 μg/kg for walnuts. The mean recovery of total aflatoxins was 95% for the Ridascreen test and 92% for immunoaffinity chromatography with fluorescence detection. For aflatoxin B₁ the mean recovery was 84%. Received: 4 March 1999 / Revised version: 17 May 1999     

Phenolic Content and Antioxidant Activity of Moscatel Dessert Wines from the Setúbal Region in Portugal

Moscatel wines from Setúbal were analyzed for their total phenolic (mean value 1,243 mg gallic acid equivalents/L), and total flavonoid (mean value 248 mg catechin/L) composition by spectrophotometric and chromatographic methods were used to quantify phenolic compounds as benzoic acids, cinnamic acids, stilbens, and some flavonoids. Antioxidant activity of the wines was evaluated by 1,1-diphenyl-2-picrylhydrazyl (DPPH; mean value 70.7% inhibition), ferric reducing antioxidant power (FRAP; mean value 3,098 mg of Trolox equivalents/L) and oxygen radical absorbance capacity (ORAC; mean value 10,724 μmol/L) assays. Results were analyzed using principal component analysis which allowed samples to be grouped in terms of both winemaking producer and vintage. By plotting correlation loadings, it was possible to understand which variables were responsible for sample distribution. The correlation between results obtained for variables show that, in general, total flavonoid content is a better estimation of antioxidant activity in Moscatel samples (r _{ORAC/flavonoids} = 0.832, r _{FRAP/flavonoids} = 0.677) than total phenolic content (r _{ORAC/phenolics} = 0.680, r _{FRAP/phenolics} = 0.372). No major correlations were detected for DPPH assay results (r _{DPPH/flavonoids} = 0.283, r _{DPPH/phenolics} = 0.271). Chromatographic profiles showed important differences among Moscatel wines. Gallic acid contents and results of antioxidant activity tests were strongly correlated (r values in the range 0.74–0.92). Correlations of the results obtained for antioxidant activity tests with contents of other phenolic compounds such as ethyl caffeate, ethyl gallate, caffeic acid, protocatechuic acid, and t-caftaric acid depend on sample and type of test employed. Presented at the “AOAC Europe section international workshop: Enforcement of European Legislation on Food and Water: Analytical and Toxicological Aspects”, in Lisbon, April 2008, and published in abstract form.     

Profiles of steroid hormones in beef from steers implanted with Synovex-S (estradiol benzoate and progesterone) in comparison to control steers

 Profiles of steroid hormones (androgens, estrogens, progestogens and corticoids), their precursors and metabolites were analyzed in nine beef samples obtained from steers which had received the anabolic implant Synovex-S (200 mg progesterone plus 20 mg estradiol benzoate) and in nine samples from control steers. Analysis of phenolic steroids was performed by enzyme immunoassay after separation by HPLC. Neutral steroids were determined by GC-MS. Concentrations of the hormones progesterone and 17β-estradiol, of their precursors and metabolites (pregnenolone, 17α-hydroxyprogesterone, dehydroepiandrosterone, androstenedione, epitestosterone, α-androsterone, 17α-estradiol, and estrone) and of the corticosteroids cortisone and hydrocortisone did not differ significantly between treatments (P>0.05) but the ratio of 17β-estradiol to its metabolites and the cortisone/hydrocortisone ratio were significantly higher in beef from treated steers (P<0.01). Concentrations of testosterone and 5α-dihydrotestosterone were below the determination limits (10 ng/kg and 20 ng/kg, respectively) in both treated and control steers.