Simultaneous voltammetric determination of phenolic antioxidants in food using a boron-doped diamond electrode

A method for the simultaneous determination of butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) in food was developed using square-wave voltammetry (SWV). The determination of these phenolic antioxidants was carried out using a cathodically pre-treated boron-doped diamond electrode (BDD) and an aqueous-ethanolic (30% ethanol, v/v) 10 mmol L⁻¹ KNO₃ solution (pH_cond. 1.5) as supporting electrolyte. In the SWV measurements using the BDD electrode, the oxidation peak potentials of BHA and BHT present in binary mixtures were separated by about 0.3 V. The attained detection limits for the simultaneous determination of BHA and BHT (0.14 and 0.25 μmol L⁻¹, respectively) are lower than the ones by voltammetric techniques reported in the literature. The proposed method was successfully applied in the simultaneous determination of BHA and BHT in food products, with results similar to those obtained using a high-performance liquid chromatography method, at a 95% confidence level.     

Gas Chromatographic Determination of Butylated Hydroxyanisole, Butylated Hydroxytoluene and Tertiarybutyl Hydroquinone in Soybean Oil

Oils containing different levels of the most common phenolic antioxidants, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), and tertiarybutyl hydroquinone (TBHQ) from 0–200 ppm were analyzed by a new gas chromatographic method. The antioxidants in oils were isolated by nitrogen gas purging, collected on Tenax GC coated with polymetaphenoxylene, and then separated and quantitated by gas chromatography. This method requires neither extraction of antioxidants from oil nor derivatization of antioxidants. The correlation coefficients (r) between gas chromatographic peak heights or peak area and their concentrations in oils were 0.99 for BHA, BHT, and TBHQ. This simple gas chromatographic method can determine as little as 10 ppm pf BHA, BHT, or TBHQ in oils in an hour.     

食用油中5种合成抗氧化剂同时检测方法研究

建立了基于高效液相色谱的一种简单、快速、准确定量分析25份食用油中没食子酸丙酯(PG)、没食子酸十二酯(DG)、叔丁基对苯二酚(TBHQ)、丁基化羟基茴香醚(BHA)和二丁基羟基甲苯(BHT) 5种合成抗氧化剂的方法。结果显示,5种合成抗氧化剂(PG、DG、TBHQ、BHA和BHT)的质量浓度在10~70μg/m L范围内与色谱峰面积呈良好线性关系,相关系数均大于0.999,检出限为0.27~0.34μg/kg,加标回收率为84.56%~101.12%,相对标准差在1.27%~4.82%之间。该方法具有良好的精确度和准确度,且在13 min内可完成5种合成抗氧化剂的分离,能够适用于食用油中合成抗氧化剂的检测分析。     

PSE-HPLC 法测定食品中叔丁基羟基茴香醚和2,6- 二叔丁基羟基甲苯

目的：建立测定食品中抗氧化剂叔丁基羟基茴香醚(BHA)和2,6- 二叔丁基羟基甲苯(BHT)加压溶剂萃取-高效液相色谱法(PSE-HPLC 法)。方法：采用正交试验对影响PSE 萃取效率的温度、压力、萃取溶剂、萃取时间进行优化,联合HPLC 进行测定,并确定分别以BHA 提取量、BHT 提取量以及总量为评价指标的最优条件。结果：PSE-HPLC 法测定BHT 和BHA 的相对标准偏差(RSD)为0.5%～3.1%,并且在1.0～200.0μg/mL 范围内色谱峰面积与组分质量浓度均有很好的线性相关性(r ≥ 0.9997),检出限为0.05μg/mL,在最优条件下的回收率为92.60%～97.80%。结论：PSE-HPLC 法简便、快速、效率高,方法的重现性、线性相关性以及检出限理想,适用于食品中BHT 和BHA 含量及两者总量的同时快速检测。     

Cloud-point extraction and reversed-phase high-performance liquid chromatography for the determination of synthetic phenolic antioxidants in edible oils

A cloud-point extraction (CPE) method using Triton X-114 (TX-114) nonionic surfactant was developed for the extraction and preconcentration of propyl gallate (PG), tertiary butyl hydroquinone (TBHQ), butylated hydroxyanisole (BHA), and butylated hydroxytoluene (BHT) from edible oils. The optimum conditions of CPE were 2.5% (v/v) TX-114, 0.5% (w/v) NaCl and 40 min equilibration time at 50 °C. The surfactant-rich phase was then analyzed by reversed-phase high-performance liquid chromatography with ultraviolet detection at 280 nm, using a gradient mobile phase consisting of methanol and 1.5% (v/v) acetic acid. Under the studied conditions, 4 synthetic phenolic antioxidants (SPAs) were successfully separated within 24 min. The limits of detection (LOD) were 1.9 ng mL(-1) for PG, 11 ng mL(-1) for TBHQ, 2.3 ng mL(-1) for BHA, and 5.9 ng mL(-1) for BHT. Recoveries of the SPAs spiked into edible oil were in the range 81% to 88%. The CPE method was shown to be potentially useful for the preconcentration of the target analytes, with a preconcentration factor of 14. Moreover, the method is simple, has high sensitivity, consumes much less solvent than traditional methods, and is environment-friendly. Practical Application: The method established in this article uses less organic solvent to extract SPAs from edible oils; it is simple, highly sensitive and results in no pollution to the environment.     

气相色谱--质谱法测定XO酱中BHA、BHT和TBHQ

采用气相色谱—质谱(全扫描方式)测定XO酱中丁基羟基茴香醚(BHA)、二丁基羟基甲苯(BHT)和叔丁基对苯二酚(TBHQ)。样品用甲醇振荡萃取，以DB—5MS为分析柱。3种组分的回收率在85％～99％之间，相对标准偏差小于8．4％；样品中BHA、BHT和TBHQ的检测限分别为0．05、0．05和0．10(mg／kg)。该法简单、快速、准确，可用于XO酱等基质复杂的富油食品中BHA、BHT和TBHQ的检测和确证。     

Determination of synthetic phenolic antioxidants in soft drinks by stir-bar sorptive extraction coupled to gas chromatography-mass spectrometry

The synthetic phenolic antioxidants butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT) and tert-butyl hydroquinone (TBHQ) were pre-concentrated by stir-bar sorptive extraction and thermally desorbed (SBSE-TD) before analysis by GC-MS. Several parameters affecting the derivatisation step and both SBSE extraction and thermal desorption were carefully optimised. When the analyses of BHA and TBHQ in their acetylated, silylated and underivatised forms were compared, the best results were obtained when the in-situ derivatisation procedure with acetic anhydride was employed. Quantification was carried out using carvacrol as the internal standard, providing quantification limits of between 0.11 and 0.15 ng ml^?1, depending on the compound. Recovery assays for samples spiked at two concentration levels, 1 and 5 ng ml^?1, provided recoveries in the 81–117% range. The proposed method was applied in the analysis canned soft drinks and the analytes were found in five of the 10 samples analysed.     

Migration analysis,antioxidant, and mechanical characterization of polypropylene-based active food packaging films loaded with BHA,BHT, and TBHQ

Polypropylene (PP) based active composite films were prepared by adding butylated hydroxy anisole (BHA), butylated hydroxytoluene (BHT), and tertiary butylated hydroquinone (TBHQ) antioxidants using the extrusion molding process. All concentrations of BHT, 2% to 3% BHA, and 3% TBHQ significantly increased the tensile strength (TS) of the composite films compared with control films. Increasing antioxidant concentration decreased TS values for BHT films, whereas an opposite trend was observed for BHA and TBHQ films. BHA at < 2%, BHT at > 2%, and TBHQ at all added concentrations significantly reduced elongation at break (E_b) of the composite films compared to control films. Water vapor permeability (WVP) of 1% BHT film was not significantly different from control. However, other antioxidants especially at increased concentrations significantly increased WVP values. TBHQ films with 300% to 662% increase had the highest WVP and BHT films with 5% to 81% increase had the lowest WVP among composite films. All three antioxidants had a negative effect on the transparency of the films; however the effect of BHA at higher concentrations was greater. The antioxidants did not change the color attributes of the films. Films containing all antioxidants showed 2,2-diphenyl-1-picrylhydrazyl radical-scavenging activity, which increased with increase in their concentration, especially for those containing 3 wt.% BHT and TBHQ. Overall, incorporating BHA and BHT into a PP matrix improved mechanical, barrier, antioxidant properties, and film appearance and consequently were proposed for the development of antioxidant active PP films. TBHQ film is not recommended for food packaging because of its weak mechanical properties (lower E_b and TS values, higher WVP, and greater migration).     

甲醇萃取法在食用油中酚类抗氧化剂检测中的应用研究

目的对比国标方法与甲醇萃取法萃取食用油中的酚类抗氧化剂。方法分别用乙酸乙酯:环己烷(1:1,V:V)萃取凝胶渗透色谱仪(gelpermeationchromatograph,GPC)进行样品净化气相色谱检测和甲醇萃取冷冻过滤气相色谱检测。结果甲醇萃取法在检测叔丁基羟基茴香醚(butyl hydroxyl acids, BHA)、2, 6-二叔丁基-4-甲基苯酚(butylated hydroxytoluene, BHT)、叔丁基对苯二酚(tertiary butylhydroquinone, TBHQ) 3种抗氧化剂在各自的线性范围内,线性关系良好,相关系数r大于0.999,相对标准偏差(relative standard deviation RSD)为0.91%～1.75%,回收率为89%～98%。结论该方法简单、快速、准确、实验成本低,适用于食用油中酚类抗氧化剂的测定。     

Determination of Four Synthetic Phenolic Antioxidants in Edible Oils by High-Performance Liquid Chromatography with Cloud Point Extraction Using Tergitol TMN-6

A cloud-point extraction (CPE) method using Tergitol TMN-6 (TMN-6) non-ionic surfactant was developed for the extraction and preconcentration of propyl gallate (PG), tertiary butyl hydroquinone (TBHQ), butylated hydroxyanisole (BHA), and butylated hydroxytoluene (BHT) in edible oils. The optimum conditions of CPE were 1.5 % (v/v) Tergitol TMN-6, 1 % (w/v) NaCl, ultrasound-assist 15 min at 49 KHz, 20 min equilibrated at 45 °C, and centrifugation for 10 min at 3,000 rpm. The surfactant-rich phase was then analyzed by reversed-phase high-performance liquid chromatography (HPLC) with ultraviolet detection at 280 nm, under gradient separation, using methanol and 1.5 % (v/v) acetic acid. Under the study conditions, four synthetic phenolic antioxidants (SPAs) were successfully separated within 24 min. Limits of detection in the studied edible oils were in the range of 1.6 to 9.0 ng mL^?1. The high recoveries of the spiked edible oils were obtained in the range 90–98 %. The CPE method has been shown to be a potentially useful methodology for the preconcentration of the target analytes, with a preconcentration factor of 25. This method was compared with cloud point extraction (using Triton X-114) and liquid–liquid extraction (using methanol).     

气相色谱法测定食用油中BHA和BHT残留量的对比研究

目的建立气相色谱法测定食用油中叔丁基羟基茴香醚(butyl hydroxyanisole,BHA)和二丁基羟基甲苯(butylated hydroxytoluene,BHT)的残留量。方法使用无水乙醇萃取样品,经中性氧化铝吸附杂质,HP-5毛细管柱分离,使用气相色谱仪定量分析BHA和BHT在食用油中的残留量。同时,与GB/T 5009.30中的方法进行对比,考察了本方法的线性、重现性、回收率和精密度。结果本方法中BHA和BHT的线性范围分别为2.02~40.48 ng和2.07~41.36 ng,标准曲线方程分别为Y=16.61X+10.03(r=0.9996)和Y=20.14X+16.56(r=0.9997);BHA和BHT的检出限分别为92.4 ng/kg和108.6 ng/kg,加标回收率分别为98.94%(相对标准偏差为0.33%)、98.69%(相对标准偏差为0.34%)。结论本实验建立的方法灵敏度高、定量准确,和国标法相比,具有简单实用的特点,适合食用油中BHA和BHT残留量的检测。     

Rapid micropreparation procedure for the gas chromatographic-mass spectrometric determination of BHT, BHA and TBHQ in edible oils

A rapid, accurate and organic solvent saving procedure has been developed for the GC/MS determination of three phenolic antioxidants butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA) and butyl hydroquinone (TBHQ) in vegetable oils. The method involves two-step microextraction and a centrifugal procedure in a 2 mL autosampler vial, consuming only 50 mg sample and total 1 mL acetonitrile. Recoveries of the phenolic antioxidants when spiked to soya bean oil, peanut oil and cereal cooking oil at 50, 200 and 250 mg/kg, respectively were in the ranges 95.6-104.3% for BHT, 99.7-107.5% for BHA and 93.6-103.8% for TBHQ with the relative standard deviation (RSD) were less than 3% for their independent measurements. The developed method was repeatable and could be applied to determine trace amounts of phenolic antioxidants in vegetable oils.     

SYNERGISTIC ACTIVITY OF CAPELIN PROTEIN HYDROLYSATES WITH SYNTHETIC ANTIOXIDANTS IN A MODEL SYSTEM

Capelin protein hydrolysates (CPHs) were examined in a β-carotene-linoleate model system together with synthetic antioxidants, namely butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), and tert-butyl hydroquinone (TBHQ). Addition of CPHs was at 0.25 and 1 mg per 5 mL in the above emulsion. BHA and BHT were added at levels of 2.5 and 5 μg and TBHQ at 5 and 10 μg. Absorbance of model emulsion system at 470 nm was recorded every 30 min for 2 h. CHPs and synthetic antioxidants inhibited oxidation of linoleic acid effectively. In the experiment with BHA, the influence of CPHs was significant (p<0.01) for the samples incubated for 60, 90, and 120 min; and in experiments with BHT and TBHQ during the entire incubation period. The influence of added BHA and BHT on inhibition of bleaching of β-carotene in the emulsion system was significant (p <0.01) during the incubation period and after 60, 90 and 120 min when TBHQ was used. A synergistic effect was observed only for CPHs and TBHQ when incubation time was 60, 90, and 120 min.     

Residue levels of food-grade antioxidants in postharvest treated in-pod peanuts during five months of storage

In order to investigate residue levels of butylated hydroxyanisole (BHA), propyl paraben (PP) and butylated hydroxytoluene (BHT) during storage, eight-hundred kilograms of bulk peanuts were treated with the following antioxidant emulsions: BHA (1802 μg g⁻¹), BHA–PP (1802 μg g⁻¹ + 1802 μg g⁻¹) M1 and BHA–PP–BHT mixtures (1802 μg g⁻¹ + 901 μg g⁻¹ + 2204 μg g⁻¹) M2 and (1802 μg g⁻¹ + 1802 μg g⁻¹ + 2204 μg g⁻¹) M3. Residues were determined in peanut pod and seed tissues at 1-month intervals during the storage. While the reduction levels of BHA and PP in pods at the end of the storage period ranged from 66% to 76%, BHT levels were decreased extensively (86%). Twenty-four hours after peanuts were treated, antioxidant emulsions effectively seeped into the seeds and low levels of these chemicals were detected during the assay. Residues of PP in seeds were lower (62%) than the other antioxidants. Although the doses used were higher than those approved for food-grade antioxidants in stored peanuts, the residue levels in seeds (32.8–0.02 μg g⁻¹) did not exceed the maximum residue limits during the storage period.     

PSE-GC法同时测定饼干中两种抗氧化剂

建立测定饼干中的2种抗氧化剂叔丁基对羟基茴香醚(BHA)和二丁基羟基甲苯(BHT)的加压溶剂萃取-气相色谱法(PSE-GC法).采用PSE法进行样品萃取,萃取液经中性氧化铝净化后,进行GC分析.PSE-GC法测定饼干中BHT和BHA的相对标准偏差(RSD)为0.5％～3.1％,并且在2.0 μg/mL～200.0 μg/mL范围内色谱峰面积与组分浓度均有很好的线性相关性(r≥0.9994),检出限为0.5 μg/mL,回收率为94.68％～96.80％.PSE-GC法简便、快速、效率高,方法的重现性、线性相关性以及检出限理想,适用于饼干中BHT和BHA含量的同时快速检测.     

Estimates of the theoretical maximum daily intake of phenolic antioxidants BHA, BHT and TBHQ in Brazil

The theoretical maximum daily intakes (TMDI) of the phenolic antioxidants butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT) and tertbutyl hydroquinone (TBHQ) in Brazil were estimated using food consumption data derived from a household economic survey and a packaged goods market survey. The estimates were based on maximum levels of use of the food additives specified in national food standards. The calculated intakes of the three additives for the mean consumer were below the ADIs. Estimates of TMDI for BHA, BHT and TBHQ ranged from 0.09 to 0.15, 0.05 to 0.10 and 0.07 to 0.12mg/kg of body weight, respectively. To check if the additives are actually used at their maximum authorized levels, analytical determinations of these compounds in selected food categories were carried out using HPLC with UV detection. BHT and TBHQ concentrations in foodstuffs considered to be representive sources of these antioxidants in the diet were below the respective maximum permitted levels. BHA was not detected in any of the analysed samples. Based on the maximal approach and on the analytical data, it is unlikely that the current ADI of BHA (0.5mg/kg body weight), BHT (0.3mg/kg body weight) and TBHQ (0.7mg/kg body weight) will be exceeded in practice by the average Brazilian consumer.     

Levels of synthetic antioxidants (ethoxyquin,butylated hydroxytoluene and butylated hydroxyanisole) in fish feed and commercially farmed fish

Several synthetic antioxidants are authorized for use as feed additives in the European Union. Ethoxyquin (EQ) and butylated hydroxytoluene (BHT) are generally added to fish meal and fish oil, respectively, to limit lipid oxidation. The study was conducted to examine the concentrations of EQ, BHT and butylated hydroxyanisole (BHA) in several commercially important species of farmed fish, namely Atlantic salmon, halibut and cod and rainbow trout, as well as concentrations in fish feed. The highest levels of BHT, EQ and BHA were found in farmed Atlantic salmon fillets, and were 7.60, 0.17 and 0.07?mg?kg^?1, respectively. The lowest concentrations of the synthetic antioxidants found were in cod. The concentration of the oxidation product ethoxyquin dimer (EQDM) was more than ten-fold higher than the concentration of parent EQ in Atlantic salmon halibut and rainbow trout, whereas this dimer was not detected in cod fillets. The theoretical consumer exposure to the synthetic antioxidants EQ, BHA and BHT from the consumption of farmed fish was calculated. The contribution of EQ from a single portion (300?g) of skinned fillets of the different species of farmed fish would contribute at most 15% of the acceptable daily intake (ADI) for a 60?kg adult. The consumption of farmed fish would not contribute measurably to the intake of BHA; however, a 300?g portion of farmed Atlantic salmon would contribute up to 75% of the ADI for BHT.     

Levels of synthetic antioxidants (ethoxyquin, butylated hydroxytoluene and butylated hydroxyanisole) in fish feed and commercially farmed fish

Several synthetic antioxidants are authorized for use as feed additives in the European Union. Ethoxyquin (EQ) and butylated hydroxytoluene (BHT) are generally added to fish meal and fish oil, respectively, to limit lipid oxidation. The study was conducted to examine the concentrations of EQ, BHT and butylated hydroxyanisole (BHA) in several commercially important species of farmed fish, namely Atlantic salmon, halibut and cod and rainbow trout, as well as concentrations in fish feed. The highest levels of BHT, EQ and BHA were found in farmed Atlantic salmon fillets, and were 7.60, 0.17 and 0.07 mg kg(-1), respectively. The lowest concentrations of the synthetic antioxidants found were in cod. The concentration of the oxidation product ethoxyquin dimer (EQDM) was more than ten-fold higher than the concentration of parent EQ in Atlantic salmon halibut and rainbow trout, whereas this dimer was not detected in cod fillets. The theoretical consumer exposure to the synthetic antioxidants EQ, BHA and BHT from the consumption of farmed fish was calculated. The contribution of EQ from a single portion (300 g) of skinned fillets of the different species of farmed fish would contribute at most 15% of the acceptable daily intake (ADI) for a 60 kg adult. The consumption of farmed fish would not contribute measurably to the intake of BHA; however, a 300 g portion of farmed Atlantic salmon would contribute up to 75% of the ADI for BHT.     

Determination and confirmation of five phenolic antioxidants in foods by LC/MS and GC/MS

Identification and determination of butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), nordihydroguaiaretic acid (NDGA), propyl gallate (PG) and tert-butylhydroquinone (TBHQ) by means of LC/MS and GC/MS were examined. These five phenolic antioxidants were detected as their pseudo-molecular ions [M-H]- by LC/MS using a Shim-pack FC-ODS column with drying gas. Moreover, BHA, BHT and TBHQ were detected based on their mass fragment ions by GC/MS. Decomposition of TBHQ, NDGA and PG during analysis could be prevented by the addition of L-ascorbic acid (AsA) to the extraction solvent. All five antioxidants were extracted from nikuman, olive oils, peanut butter, pasta sauce and chewing gum with a mixture of acetonitrile-2-propanol-ethanol (2:1:1) containing 0.1% AsA (AsA mixture), which had been cooled in a freezer and filtered. One part filtrate and 5 parts water were mixed and placed on a Mega-Bond Elut C18 cartridge, except in the case of chewing gum. Lipids in foods were removed on a C18 cartridge by washing with 5 mL of 5% acetic acid, and antioxidants were eluted with 5 mL of AsA mixture. The antioxidants spiked into nikuman, olive oil, peanut butter, pasta sauce and chewing gum were successfully identified and their concentrations determined by LC/MS, and GC/MS with good recoveries.     

Antioxidant Properties of Rosemary Oleoresin in Turkey Sausage

Rosemary oleoresin (20 ppm) was used as an antioxidant in turkey breakfast sausages prepared with 75% hand deboned turkey meat and 25% mechanically deboned turkey meat. It was compared to similarly formulated products with butylated hydroxyanisole/butylated hydroxytoluene (BHA/BHT, 200 ppm) and a control with no antioxidants. 2-Thiobarbituric acid-reactive substances in samples stored at 4°C demonstrated that rosemary oleoresin was comparable to a commercial blend of BHA/BHT/citric acid in suppressing lipid autoxidation. Sensory analysis was in agreement with these results. Analysis of volatile aroma compounds revealed the occurrence of oxidatively derived carbonyls in the sausages without antioxidants, while the antioxidant-treated sausages were essentially free from these carbonyls.