花椒叶提取物对烤牛肉饼杂环胺形成的影响

以牛肉和花椒叶为研究对象,研究花椒叶提取物（Zanthoxylum bungeanum Maxim. leaf extract,ZME）添加量（0.015%、0.030%、0.045%）对烤牛肉饼中杂环胺（heterocyclic amines,HAs）形成的影响。结果表明,与对照组相比,ZME能够显著抑制烤牛肉饼中总HAs的形成（P＜0.05）,对其最大抑制率为39.87%,但对不同种类HAs形成的影响不同。其中,添加0.045% ZME对2-氨基-1-甲基-6-苯基咪唑并[4,5-b]吡啶、2-氨基-3-甲基咪唑并[4,5-f]喹啉、2-氨基-3,4-二甲基咪唑并[4,5-f]喹啉、1-甲基-9H-吡啶并[3,4-b]吲哚和2-氨基-9H-吡啶并[2,3-b]吲哚的抑制率分别达到71.76%、78.02%、49.07%、35.82%和100%;而0.045% ZME却促进2-氨基-3,8-二甲基咪唑并[4,5-f]喹喔啉和9H-吡啶并[3,4-b]吲哚的形成。进一步分析ZME对烤牛肉饼中HAs前体物的影响,结果显示前体物的消耗随着ZME添加量的增加呈降低趋势,相关性分析表明HAs的形成与多种游离氨基酸的消耗显著相关。上述结果表明ZME能显著抑制烤牛肉饼中HAs的形成,为其提高加工食品安全性及更广泛的应用提供理论依据。     

熟肉制品中杂环胺的形成与抑制研究进展

杂环胺是熟肉制品中最常见的危害物,其种类繁多,形成途径复杂,抑制机制也不尽相同。本文介绍了2 类杂环胺的结构,主要阐述喹啉和喹喔啉类、2-氨基-1-甲基-6-苯基咪唑[4,5-b]吡啶、β-咔啉类（1-甲基-9H-吡啶[4,3-b]吲哚（1-methyl-9H-pyrido[4,3-b]indole,harman）、9H-吡啶[4,3-b]吲哚（9H-pyrido[4,3-b]indole,norharman））以及结合态杂环胺的形成途径,归纳减少杂环胺形成的措施及机理（控制加工条件和前体物、添加外源物质清除自由基和中间体、抑制美拉德反应等）,并对目前的研究现状进行概括。     

高效液相色谱法测定烧烤制品中5种杂环胺的含量

目的 建立高效液相色谱法检测烧烤制品中5种杂环胺(heterocyclic aromatic amines, HAAs)含量的方法。方法 样品经乙酸乙酯、三乙胺、氨水提取, 丙基磺酸(propanesulfonic acid, PRS)和C18固相萃取小柱净化, 采用TSK-gel ODS-80TM色谱柱分析, 以乙腈和0.05 mol/L醋酸-醋酸铵缓冲液(pH=3.4)为流动相进行梯度洗脱, 紫外-荧光检测器的串联方式检测杂环胺含量。结果 2-氨基-1-甲基-6-苯基-咪唑并[4,5-b]吡啶(2-amino-1-methyl-6-phenylimidazo(4,5-b)pyridine, PhIP)、9H-吡啶并[4,3-b]吲哚(9H-pyrido[4,3-b]indole, Norharman)、1-甲基-9H-吡啶并[4,3-b]吲哚(1-methyl-9H-pyrido[4,3-b]indol, Harman)、2-氨基-9H-吡啶并[2,3-b]吲哚(2-amine-9H-pyrido[2,3-b]indol, AaC)在0.1~500 μg/L范围呈良好的线性关系, 2-氨基-3-甲基咪唑并[4,5-f]喹啉(2-amino-3-methylimidazo(4,5-f)quinoline, IQ)在0.1~1000 μg/L范围呈良好的线性关系, 相关系数r2均大于99.3%, 加标回收率为74.06%~93.77% (n=6), 相对标准偏差(relative standard deviation, RSD)为3.41%~5.93% (n=6)。结论 该方法简便快速、结果准确、灵敏度高, 适合于肉制品中的杂环胺含量的检测。通过检测结果可知不同原料中5种杂环胺含量不同, 相同原料烧烤条件不同, 产生的杂环胺含量也不相同。     

模型体系中PhIP、Norharman、Harman 3种杂环胺的形成与抑制

采用模型体系探讨2-氨基-1-甲基-6-苯基-咪唑并[4,5-b]吡啶（2-amino-1-methyl-6-phenylimidazo[4,5-b] pyridine,PhIP）、9H-吡啶并[3,4-b]吲哚（9H-pyrido[3,4-b]indole,norharman）、1-甲基-9H-吡啶并[3,4-b]吲哚（1-methyl-9H-pyrido[3,4-b]indole,harman）3 种杂环胺的形成规律及抑制措施。结果表明：随着加热温度的升高与加热时间的延长,模型体系中PhIP、Norharman和Harman的形成量均不断增多,其中PhIP对加热温度较为敏感,100、125 ℃反应20 min不能形成PhIP,150 ℃加热时PhIP生成量开始逐渐增多,175～200 ℃加热时PhIP形成量急剧增加;单独加热色氨酸即能产生Norharman和Harman,加入葡萄糖时Norharman和Harman的形成量进一步提高;本研究建立的同时检测色氨酸、Norharman和Harman的色谱方法明确表明,色氨酸是Norharman和Harman的前体物;高良姜素及其类似物山柰酚和槲皮素均能在一定程度上减少PhIP的形成,但只有高良姜素能降低Harman和Norharman的形成量,而山柰酚和槲皮素不但没有抑制作用反而在一定程度上提高了Harman和Norharman的形成量,进一步证实β-咔啉类杂环胺形成的复杂性。     

肉制品中PhIP的形成及抑制机理研究进展

2-氨基-1-甲基-6-苯基咪唑并[4,5-b]吡啶（2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine,PhIP）是肉制品在热加工中产生的有害物——杂环胺（heterocyclic amines,HCA）的重要成分。PhIP通过肉制品介质进入人体后,有致癌和致突变的风险。为了避免或降低PhIP对人体的危害,在不影响肉制品品质的前提下合理控制PhIP的含量,是今后研究的一个重点方向。该文就PhIP的危害、形成及抑制机理进行综述,以期为有效抑制肉制品中PhIP的含量提供理论参考。     

抗氧化剂对油炸肉制品品质及杂环胺形成的影响

系统全面分析GB 2760—2014《食品添加剂使用标准》允许添加至油炸肉制品使用的8 种抗氧化剂对3 种炸肉饼食用品质及杂环胺（heterocyclic amines,HAs）形成的影响。结果发现,不同抗氧化剂对不同种类肉制品的品质影响不同。竹叶提取物（extract of bamboo leaves,BL）、植酸钠（phytic acid,PA）、鼠尾草酸（carnosic acid,CA）、迷迭香酸（rosmarinci acid,RA）及茶多酚（tea polyphenols,TP）具有良好的保持3 种肉饼油炸过程中水分含量的能力,其能够降低油炸损失率,改善嫩度和质构特性等。不同抗氧化剂对炸肉饼中不同种类HAs形成的抑制活性有一定差异。炸鸡肉饼中,山梨酸钾（potassium sorbate,PS）对2-氨基-1-甲基-6-苯基咪唑并[4,5-b]吡啶（2-amino-1-methyl-6-phenylimidazo[4,5-b]-pyridine,PhIP）的抑制率相对最高（48%）,CA表现出对2-氨基-3,8-二甲基咪唑并[4,5-f]喹喔啉（2-amino-3,8-dimethyl-imidazo[4,5-f]-quinoxaline,8-MeIQx）相对最高的抑制率（56%）,PA、CA和PS显著降低炸鸡肉饼中总HAs含量（P＜0.05）;对于炸牛肉饼,CA对PhIP的抑制效果相对最佳,并且其与BL对8-MeIQx的抑制效果显著优于其他6?种抗氧化剂（P＜0.05）,CA、BL和PS显著抑制炸牛肉饼中总HAs的形成（P＜0.05）;炸猪肉饼中,BL对PhIP表现出相对最强的抑制活性（抑制率为64%）,8?种抗氧化剂均能显著抑制8-MeIQx和2-氨基-3,4,8-三甲基咪唑并[4,5-f]喹喔啉的形成（P＜0.05）,并且BL对总HAs表现出相对最佳的抑制效果,抑制率为49%。总体而言,BL、CA、PA、TP、RA及PS对油炸肉制品中HAs的形成表现出相对更优的抑制活性。     

葡萄籽提取物对烤羊肉中杂环胺形成的影响

将0.05%VE,0.1%与0.5%葡萄籽提取物,0.1%与0.5%槲皮素分别添加于羊肉表面,在200℃下煎烤10 min,利用固相萃取-配备二极管阵列检测器和荧光检测器的高效液相色谱分析烤羊肉中15种杂环胺的形成量,以探讨天然提取物对烤羊肉中杂环胺形成量的影响。结果表明:烤羊肉中共检测出10种杂环胺,其中极性杂环胺4种,非极性杂环胺6种,总量达51.68 ng/g。在极性杂环胺中2-氨基-1-甲基-6-苯基-咪唑并[4,5-b]吡啶(PhIP)的形成量较高,达10.50 ng/g;非极性杂环胺中9H-吡啶并[3,4-b]吲哚(Norharman)与1-甲基-9H-吡啶并[3,4-b]吲哚(Harman)的形成量较高,分别达19.66 ng/g与12.23 ng/g。烤羊肉中添加天然抗氧化剂只对极性杂环胺有抑制作用,其中添加0.5%葡萄籽提取物可以显著抑制2-氨基-3甲基咪唑并[4,5-f]喹啉(IQ),2-氨基-3,8-二甲基咪唑并[4,5-f]喹喔啉(MeIQx),2-氨基-3,4,8-三甲基咪唑并[4,5-f]喹喔啉(4,8-DiMeIQx)与PhIP 4种极性杂环胺的形成(P<0.05),其生成量分别减少36.65%,67.73%,35.63%与30%。天然抗氧化剂对烤羊肉中非极性杂环胺的抑制作用不明显。     

温和条件下模型体系中烧烤风味及杂环胺形成测定

以美拉德模型体系葡萄糖-肌酸酐-氨基酸（丙氨酸、苏氨酸、甘氨酸）为研究对象,探索3 个体系在130 ℃条件下反应3 h后风味物质及杂环胺的形成。采用固相微萃取-气相色谱-质谱联用方法检测表明,3 种模型均产生烧烤风味物质,主要为烷基吡嗪类。高效液相色谱分析表明,丙氨酸模型（Ⅰ）和甘氨酸模型（Ⅲ）均检测到2-氨基-3,4-二甲基咪唑并[4,5-f]喹啉、2-氨基-3,4,8-三甲基咪唑并[4,5-f]喹喔啉和2-氨基-3,7,8-三甲基咪唑并[4,5-f]喹喔啉3 种杂环胺,苏氨酸模型（Ⅱ）检测到了2-氨基-3,4-二甲基咪唑并[4,5-f]喹啉和2-氨基-3,4,8-三甲基咪唑并[4,5-f]喹喔啉2 种杂环胺;3 种模型体系均未检测到2-氨基-3-甲基咪唑并[4,5-f]喹啉和2-氨基-3,8-二甲基咪唑并[4,5-f]喹喔啉。130 ℃温和条件下,1.5 h内各模型体系中杂环胺的生成量很少,1.5 h后杂环胺总量随着加热时间的延长逐渐增多,3 h时模型Ⅰ、Ⅱ、Ⅲ中杂环胺总量分别为（375.50±15.80）、（414.00±18.40）、（363.50±12.20） ng/mL。本研究为肉制品加工尤其是烤肉制品加工如何控制加工条件,从而实现美拉德反应定向控制、减少杂环胺的产生提供一定参考。     

3种熏烤鸡肉制品中杂环胺含量的检测与比较

目的 以3种熏烤鸡肉制品(鸡胗、鸡翅、鸡爪)为研究对象, 通过高效液相色谱测定其中5种杂环胺类物质(heterocyclic aromatic amines, HAAs), 即2-氨基-3-甲基咪唑并[4,5-f]喹啉(2-Amino-3- methylimidazo(4,5-f)quinoline, IQ)、2-氨基-1-甲基-6-苯基-咪唑并[4,5-b]吡啶(2-Amino-1-methyl- 6-phenylimidazo(4,5-b)pyridine, PhIP)、9H-吡啶并[4,3-b]吲哚(9H-pyrido[4,3-b]indole, Norharman)、1-甲基-9H-吡啶并[4,3-b]吲哚(1-methyl-9H-pyrido[4,3-b]indol, Harman)、2-氨基-9H-吡啶并[2,3-b]吲哚(2-amine-9H-pyrido[2,3-b]indol, AaC)的含量并进行比较。方法 采用二元流动相乙腈/醋酸-醋酸铵(pH=3.4)进行梯度洗脱, 其中乙腈/醋酸-醋酸铵随时间配比为: 0 min: 10%/90%; 10 min: 20%/80%; 25 min: 50%/50%; 35 min: 10%/90%。紫外检测波长263 nm; 荧光激发波长/发射波长随时间改变为0 min: 300/440 nm; 17 min: 315/390 nm; 21 min: 335/410 nm。结果 在3种鸡肉熏烤制品中提取的5种杂环胺类物质中, PhIP的含量最高, 且在鸡胗中最为显著, 高达152.38 ng/g, 工业化生产的鸡胗中PhIP含量仅为4.23 ng/g; 各产品中Harman的含量最低, 且在鸡爪产品及工业化生产的鸡翅产品中未检出; 熏烤的鸡肉制品中提取的IQ、PhIP、Norharman、Harman、AaC的含量均高于工业化产品。结论 工业化生产的鸡胗、鸡翅、鸡爪中的5种HAAs的含量均低于3家传统熏烤产品的含量, 传统熏烤条件下鸡肉制品的食用安全系数相对较低, 工业化产品的安全性相对较高。     

杂环胺人工抗原的合成以及多克隆抗体的制备

为建立适用于一类杂环胺的酶联免疫吸附检测方法(enzyme-linked immunosorbent assay,ELISA),利用改良的碳化二亚胺法将在2-氨基-3,4,8-三甲基咪唑[4,5-f]-喹喔啉(2-amino-3,4,8-trimethyl-3H-imidazo[4,5-f]quinoxaline,4,8-DiMeIQx)的2-氨基处连接丁二酸单甲酯酰氯制备的半抗原偶联蛋白获得人工抗原。该方法利用适当pH值的缓冲体系,将酯的水解和蛋白偶合一步完成,与传统方法相比,有效地节省了反应时间和成本,且对人工抗原的紫外扫描验证和多克隆抗体效价检测结果都直接和间接地表明偶合是成功的。最终免疫获得4,8-DiMeIQx结构类似物的多克隆抗体,该抗体的最高效价为1∶450 000,且经直接竞争ELISA检测,该抗体对目标物4,8-DiMeIQx的灵敏度(IC50)为24.0μg/L,最低检测限(IC15)为1.8μg/L,对其结构类似物7,8-DiMeIQx、8-Me IQx、2-氨基-3-甲基咪唑[4,5-f]-喹喔啉(IQx)、2-氨基-3,4,7,8-四甲基咪唑[4,5-f]-喹喔啉(Tri Me IQx)的灵敏度分别为35.0、30.0、28.0、40.0μg/L,而其他与目标物结构相差较大的杂环胺,像2-氨基-1-甲基-6-苯基咪唑[4,5-b]吡啶(Ph IP)、2-氨基-3-甲基咪唑[4,5-f]喹啉(IQ)和2-氨基-3,4-二氨基咪唑[4,5-f]喹啉(2-amino-3,4-dimethyl-imidazo[4,5-f]quinoline,Me IQ),它们几乎不与抗体结合(CR0.01%)。由此可见,可以利用该抗体建立高效快速的杂环胺ELISA检测方法用以定量或定性检测肉类加工食品中的一类杂环胺。     

Lack of formation of heterocyclic amines in fumes from frying French fries

The formation of heterocyclic amines (HAs) in the fumes from frying French fries in soybean oil or lard was studied. A high-pressure liquid chromatography method was used to determine the various HAs in fumes. Results showed that the yields of fumes produced from soybean oil when heated alone for 2 or 4 h were higher than from lard; however, a reversed trend was found when frying French fries in soybean oil and lard. Most fumes from soybean oil and lard while frying French fries were adsorbed onto the condensation apparatus, while the other portions were adsorbed onto the wool and glass beads, which were incorporated in our experimental design for collecting the fumes. The fumes from soybean oil when heated alone were found to contain three HAs, namely, 2-amino-3-methylimidazo[4,5-f]quinoxaline (IQx), 2-amino-3-methylimidazo[4,5-f ]quinoline (IQ), and 1-methyl-9H-pyrido[4,3-b ]indole (Harman), whereas two more HAs, 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ) and 3-amino-1,4-dimethyl-5H-pyrido[4,3-b ]indole (Trp-P-1), were generated in lard. Lard was more susceptible to the formation of HAs than soybean oil when both were heated alone. No HAs were detected in the fumes from French fries fried in soybean oil and lard.     

Formation of heterocyclic amines during cooking of duck meat

Heterocyclic amines (HAs) are an important class of food mutagens and carcinogens produced in meat cooked at high temperature. In the present study, the effects of various cooking methods: boiling, microwave cooking, charcoal-grilling, roasting, deep-frying and pan-frying on the formation of HAs in duck breast were studied. The various HAs formed during cooking were isolated by solid-phase extraction and analysed by HPLC. Results showed that both the varieties and contents of HAs and the cooking loss of duck breast increase along with increasing cooking temperature and time. Pan-fried duck breasts contained the highest amount of total HAs, followed by charcoal-grilling, deep-frying, roasting, microwave cooking and boiling. 9H-pyrido[3,4-b]indole (norharman) and 1-methyl-9H-pyrido[3,4-b]indole (harman) were detected in all of the cooked duck meat, with levels in the range of 0.1–33?ng?g^?1. 2-Amino-1-methyl-6-phenylimidazo[4,5-f]pyridine (PhIP) was formed easily in duck meat cooked by pan-frying and charcoal-grilling in the range of 0.9–17.8?ng?g^?1. 2-Amino-3-methylimidazo[4,5-f]quinoline (IQ) was identified in duck meat cooked by charcoal-grilling and pan-frying, in the range of 0.4–4.2?ng?g^?1. 2-Amino-3,8-dimethyl-imidazo[4,5-f]quinoxaline (MeIQx) was detected in amounts below 4.5?ng?g^?1 in duck meat cooked by charcoal-grilling, roasting, deep-frying and pan-frying. The other HAs were detected in amounts below 10?ng?g^?1. Colour development increased with cooking temperature, but no correlation with HAs’ content was observed.     

Effects of various additives on the formation of heterocyclic amines in fried fish fibre

The effects of various additives on the formation of heterocyclic amines (HAs) in fried fish fibre (Trachinooephlus myops) were studied. Fried fish fibre was prepared by boiling raw snake fish, followed by deboning, eviscerating, separating of fish meat and pressing. The fish meat was subjected to frying, during which treatment the additives, such as sugar, monosodium glutamate (MSG), antioxidants and edible oil, were added. The HAs were analyzed by high-performance liquid chromatography (HPLC) with diode-array detection. Results showed that the formation of HAs was retarded after the addition of a high level of sugar (19%), and the amount of 9H-pyrido-[4,3-b]indole (Norharman), 1-methyl-9H-pyrido-[4,3-b]indole (Harman), 2-amino-9H-pyrido[2,3-b]indole (AαC) or 2-amino-3-methyl-9H-pyrido[2,3-b]indole (MeAαC) also decreased to a minimum. The total amount of HAs rose with increasing levels of MSG, and the individual HAs, Norharman, Harman, AαC and MeAαC showed the same trend. Antioxidants, such as vitamin C, α-tocopherol and BHT (Butylated hydroxytoluene), did not show any consistent effect of concentration on HAs formation. Coconut oil contributed to the highest levels of HAs formation, followed by lard and soybean oil.     

Formation of heterocyclic amines in a model system during heating

The formation of heterocyclic amines (HAs) in a model system during heating at 100, 150, or 200 degrees C for varied lengths of time was studied. The following systems were used: (i) phenylalanine, (ii) creatinine, (iii) phenylalanine and glucose, (iv) phenylalanine and creatinine, (v) glucose and creatinine, and (vi) phenylalanine, glucose, and creatinine. Results showed that HAs could only be found in both systems of glucose and creatinine, and of phenylalanine, glucose, and creatinine. Both 2-amino-9H-pyrido-[2,3-b]indole (AalphaC) and 2-amino-3-methyl-9H-pyrido-[2,3-b]indole (MeAalphaC) were observed in the former system, and the formation rate of AalphaC was higher than MeAalphaC. For the latter system, 2-amino-3-dimethylimidazo[4,5-f]quinoxaline (IQx), 9H-pyrido-[4,3-b]indole (Norharman), 1-methyl-9H-pyrido-[4,3-b]indole (Harman), AalphaC, and MeAalphaC were present. The formation rate of AalphaC was the highest at 200 degrees C, followed by MeAalphaC, Harman, Norharman, and IQx. In addition, the varieties of HAs increased both with increasing heating time and temperature. The amounts of HAs formed were less in the model system of glucose and creatinine than that of phenylalanine, glucose, and creatinine. The same trend was also observed for the formation rate of HAs. At 150 or 200 degrees C, the amounts of IQx, Harman, Norharman, AalphaC, and MeAalphaC increased in the initial period of heating and then reached a plateau. The results of this study provided a basic understanding of the conditions that result in the formation of HAs during cooking of meat and fish products.     

Effects of precursor composition and water on the formation of heterocyclic amines in meat model systems

Model systems based on pressed meat from ox, pork and chicken were used to study the formation of carcinogenic/mutagenic heterocyclic amines (HAs). The composition of precursors (free amino acids, creatine and glucose) was examined and samples were heated in test-tubes under wet and dry conditions at 175 and 200°C for 30 min. Several HAs were detected, and the formation of DMIP (2-amino-1,6-dimethylimidazo[4,5-b]-pyridine), TMIP (2-amino-1,5,6-trimethyl-imidazo[4,5-b]-pyridine), IFP (2-amino-1,6-dimethylfuro[3,2-e]imidazo[4,5-b]-pyridine) and PhIP (2-amino-1-methyl-6-phenylimidazo[4,5-b]-pyridine) was found to be favoured by dry heating conditions. Highest amounts of PhIP and IFP were detected in heated meat juice from chicken breast, while more MeIQx (2-amino-3,8-dimethylimidazo[4,5-f]-quinoxaline) was found in heated meat juices from roast beef and pork chop. Norharman (9H-pyrido[3,4-b]-indole) and Harman (1-methyl-9H-pyrido[3,4-b]-indole) were also detected at high levels.     

新疆传统腌制对烤羊肉食用品质及杂环胺含量的影响

为了改善烤羊肉的风味、色泽、嫩度等食用品质,减少杂环胺（heterocyclic amines,HAs）的形成,本实验以羊肉为对象,研究了不同新疆传统腌制料（红辣椒（H）、洋葱（Y）、孜然（Z）、蛋清（Q））对烤羊肉水分质量分数、持水力、色泽、嫩度、质构特性及HAs含量的影响。结果表明：不同的腌制料对烤羊肉的食用品质有不同影响,与其他各组相比,Y组的水分质量分数最低（P＜0.05）,且烤制损失率最高（P＜0.05）;Z组和两个混合组（HZY和HZYQ）的烤羊肉具有更好的持水能力,其烤制损失率显著低于其他各组（P＜0.05）;除HZY组外,其他各组的亮度（L*）均显著高于对照组（P＜0.05）;除Q组外,其他腌制料烤前处理均能够显著改善烤羊肉的黄度（b*）,赋予烤肉更好的焦黄色;H组、Q组、HZY组和HZYQ组的剪切力均显著低于不添加任何腌制料的对照组（P＜0.05）,能够显著改善烤羊肉的嫩度;相对而言,Q组、HZY组和HZYQ组具有更优的质构特性;不同腌制料均能够显著降低烤羊肉饼中2-氨基-3-甲基咪唑并[4,5-f]喹啉、2-氨基-1-甲基-6-苯基咪唑并[4,5-b]吡啶和2-氨基-9H-吡啶并[2,3-b]吲哚的生成量（P＜0.05）,相对而言,洋葱是最为有效的HAs抑制剂,其对总HAs的抑制率最高（53.71%）。本研究为新疆传统腌制羊肉方法的进一步推广应用提供了理论依据。     

Antioxidant spices reduce the formation of heterocyclic amines in fried meat

 Heterocyclic aromatic amines (HAs) are mutagenic compounds that are formed during heating of meat and fish. These substances are reaction products of creatine with amino acids and carbohydrates. It is recommended that exposure to these probable human carcinogens should be minimised. Five heterocyclic aromatic amines which occur in beef were investigated: 2-amino-3-methyl-imidazo[4,5-f]quinoline (IQ), 2-amino-3,4-dimethyl-imidazo[4,5-f]quinoline (MeIQ), 2-amino-3,8-dimethyl-imidazo[4,5-f]quinoxaline (MeIQx), 2-amino-3,4,8-trimethyl-imidazo[4,5-f]quinoxaline (4,8-DiMeIQx), and 2-amino-1-methyl-6-phenyl-imidazo[4,5-b]pyridine (PhIP). Clean-up was done by acid-base partition followed by SPE using blue cotton. HPLC analysis was carried out by using electrochemical detection for IQ- and IQx-type compounds and fluorescence detection for PhIP. The concentrations of the aromatic amines were as follows: IQ, 10.2 μg/kg; MeIQ, 2.46 μg/kg; MeIQx, 13.2 μg/kg; 4,8-DiMeIQx, 2.26 μg/kg; and PhIP, 5.48 μg/kg. The application of spices (rosemary, thyme sage, garlic, brine) reduced the content of the HAs below 60% of the amount found in the control. Received: 23 April 1998