Amount Of Heterocyclic Amines Research Articles

Influence of antioxidants in virgin olive oil on the formation of heterocyclic amines in fried beefburgers

An association between the intake of heterocyclic amines (HAs) and the development of cancer has been observed in some epidemiological studies, while in other studies no such correlation has been found. HAs are mutagenic/carcinogenic compounds formed at low levels via the Maillard reaction and a free radical mechanism during cooking of animal tissue. The addition of pure antioxidants or foods containing antioxidants has previously been shown to decrease the amount of HAs formed during cooking. In this study, beefburgers were fried in six different oils: refined olive oil, virgin olive oil, virgin olive oil depleted of phenols, rapeseed oil, virgin olive oil with rosemary extract and refined olive oil with rosemary extract. The content of antioxidative compounds in the virgin olive oil and the rosemary extract was determined. The beefburgers were analysed with regards to 12 different HAs by solid phase extraction and HPLC analysis. MeIQx, 4,8-DiMeIQx, PhIP, Harman and Norharman were detected in all beefburgers fried in the different oils, but the relative amounts varied. Frying in virgin olive oil reduced the formation of HAs compared with refined olive oil. This effect is probably due to the content of phenols in the virgin olive oil. The HA-reducing effect of virgin olive oil decreased during storage, but the addition of rosemary extract may prevent this decrease.

Comments on the history and importance of aromatic and heterocyclic amines in public health

The carcinogenic risk of aromatic amines in humans was first discovered when a physician related the occurrence of urinary bladder cancer to the occupation of his patients. They were employed in the dyestuff industry, chronically exposed to large amounts of intermediate arylamines. Laboratory investigations disclosed that rats and mice administered specific azo dyes arylamines or derivatives developed cancer, primarily in the liver. Also, at that time, a possible pesticide, 2-aminofluorene, was tested for chronic toxicity, revealing that it rapidly induced cancers in several organs of rodents. This led to investigations on the mode of action of this class of chemicals, including their metabolic conversion. Biochemical activation to more reactive N-hydroxy compounds was found to occur, mostly in the liver, through what is now known as the cytochrome P450 enzyme systems, and also through prostaglandin synthetases. There were species differences. Guinea pigs were resistant to carcinogenesis because of the low titer of the necessary activating enzymes. In target tissues, a second essential reaction was necessary, namely acylation or sulfate ester formation. The reactive compounds produced display attributes of genotoxicity in appropriate test systems. Interest in this class of compounds increased when of Sugimura and colleagues discovered the formation of mutagens at the surface of cooked meat or fish, that were identified as heterocyclic amines (HCAs). These compounds undergo the same type of activation reactions, as do other arylamines. Epidemiological data suggest that meat eaters may have a higher risk of breast and colon cancer. HCAs induced cancer in rats in these organs and also in the prostate and the pancreas. In addition, there is some evidence that they affect the vascular system. The formation of HCAs during cooking can be decreased by natural and synthetic antioxidants, by tryptophan or proline, or by removing the essential creatine through brief microwave cooking prior to frying or broiling. The amounts of HCAs in cooked foods are small, but other components in diet such as ω-6-polyunsaturated oils have powerful promoting effects in target organs of HCAs. On the other hand, the action of HCAs may be decreased by foods containing antioxidants, such as vegetables, soy, and tea. Some constituents in foods also induce phase II enzymes that detoxify reactive HCA metabolites. Additional mechanisms involved decreased growth of neoplasms by intake of protective foods. Possibly, the carcinogenic effect of HCAs is accompanied by the presence of reactive oxygen species (ROS), which are also inhibited by antioxidants. World-wide, there have been many contributors to knowledge in this field. Adequate information may permit now to adjust lifestyle and lower the risk of human disease stemming from this entire class of aryl and HCA.

Screening for heterocyclic amines in chicken cooked in various ways

Chicken cooked under well-controlled conditions and commercial chicken products were screened for heterocyclic amines (HAs). Chicken samples were boiled, deep-fried, pan-fried, oven-roasted, cooked in an unglazed clay pot or in a roasting bag in the oven, and oven broiled. 2-amino-3,8-dimethylimidazo[4,5- f]quinoxaline (MeIQx), 2-amino-3,4,8-trimethylimidazo[4,5- f]quinoxaline (4,8-DiMeIQx), 2-amino-1-methyl-6-phenylimidazo[4,5- b]pyridine (PhIP), 1-methyl-9 H-pyrido[3,4- b]indole (harman) and 9 H-pyrido[3,4- b]indole (norharman) were identified in several samples. Chicken cooked at low temperatures contained low amounts of HAs. In pan-fried chicken breasts, MeIQx was detected in amounts below 2 ng/g, 4,8-DiMeIQx below 0.6 ng/g, and PhIP in amounts up to 38 ng/g. Harman and norharman were detected in almost all samples (below 15 ng/g). In skin from a commercially barbecued chicken, MeIQx, 4,8-DiMeIQx and PhIP were detected, while only traces of MeIQx were detected in the meat. MeIQx was detected in a commercial chicken flavour, 0.1 ng/ml. No HAs were detected in pan-fried chicken liver. The results show that the content of HAs in chicken cooked in various ways is low if prepared at low temperatures, and increases with increasing cooking temperature. PhIP formation seems to start accelerating at cooking temperatures around or above 200 °C. Colour development increases with cooking temperature, but no correlation with HA content was observed.

Effects of soy sauce and sugar on the formation of heterocyclic amines in marinated foods

The effects of soy sauce and sugar on the formation of heterocyclic amines (HAs) in marinated pork, eggs, and bean cakes were studied. Food samples were immersed in water in the presence of various levels of soy sauce and sugar, and the mixtures were subjected to simmering at 98±2 °C for 1 h in a closed saucepan. The various HAs in marinated food samples were analyzed by HPLC with photodiode–array detection. Results showed that seven HAs: 2-amino-3-methylimidazo[4,5- f]quinoline (IQ); 2-amino-3,8-dimethylimidazo[4,5- f]quinoxaline (MeIQx); 2-amino-3,4-dimethylimidazo[4,5- f]quinoline (MeIQ); 2-amino-3,4,8-trimethylimidazo[4,5- f]quinoxaline (4,8-DiMeIQx); 3-amino-1,4-dimethyl-5 H-pyrido[4,3- b]indole (Trp-P-1); 2-amino-1-methyl-6-phenylimidazo[4,5- f]pyridine (PhIP); and 2-amino-9 H-pyrido[2,3,- b]indole (AαC) were detected in marinated pork, while five HAs: IQ, MeIQx; 4,8-DiMeIQx; PhIP; and AαC in bean cakes, as well as four HAs, MeIQx, 4,8-DiMeIQx, Trp-P-1 and PhIP in eggs. In most samples PhIP was formed in largest amount, followed by MeIQx, 4,8-DiMeIQx, IQ, AαC, Trp-P-1 and MeIQ. The amounts of HAs produced in marinated food samples followed an increased order for each increasing level of soy sauce or sugar. Marinated juice was found to contain a higher content of HAs than marinated foods.

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

Abstract 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 Fried Fish Fiber during Processing and Storage

The formation of heterocyclic amines (HAs) in fried fish fiber during processing and storage was studied. Fried fish fiber was prepared by boiling of raw fish, followed by eviscerating, pressing, chopping, and then the fish meat was subjected to frying, during which the various additives such as sugar, soybean sauce, and edible oil were added. The various HAs in fried fish fiber were analyzed by high-performance liquid chromatography with photodiode-array detection. Only four HAs, Norharman, Harman, 2-amino-9H-pyrido[2,3-b]indole, and 2-amino-3-methyl-9H-pyrido[2,3-b]indole were detected in fried fish fiber. The amount of HAs increased with increasing frying temperature. Amino acids might play a more important role for HA formation than reducing sugar during processing of fried fish fiber. During storage, the HAs increased with increasing storage temperature when the fried fish fiber was packed in an aluminum foil bag. However, the relationship between storage temperature and HAs formation was not consistent when the fried fish fiber was packed in a plastic bag.

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°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 (AαC) and 2-amino-3-methyl-9H-pyrido-[2,3-b]indole (MeAαC) were observed in the former system, and the formation rate of AαC was higher than MeAαC. 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), AαC, and MeAαC were present. The formation rate of AαC was the highest at 200°C, followed by MeAαC, 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°C, the amounts of IQx, Harman, Norharman, AαC, and MeAαC 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.

Formation of Heterocyclic Amines in Cooked Chicken Legs

The effects of frying and microwave cooking on generation of heterocyclic amines (HAs) in chicken legs with skin and without skin were studied. Chicken legs were microwave-cooked at 2,450 MHz for 5,10, and 15 min with an output power of 700 W. Frying of chicken legs was conducted at 100 and 150°C for 15 min and at 200°C for 5, 10, and 15 min. The various HAs were analyzed by HPLC with diode-array detection. Results showed that both the varieties and contents of HAs and the weight losses of chicken legs increased along with increasing cooking temperature and time. With skin both the amounts of HAs and weight losses of chicken legs were less than those without skin under the same heating conditions. The weight losses of microwave-cooked chicken legs were higher than those of fried chicken legs. The formation of the aminomethylimidazoquinoline type of HAs could be reduced by choosing microwave cooking in place of frying. Frying led to the formation of both the aminomethylimidazoquinoline and the carboline types of HAs.

Effect of commercial marinades on the mutagenic activity, sensory quality and amount of heterocyclic amines in chicken grilled under different conditions

The effect of processing conditions on the mutagenic activity and sensory quality of everyday food was studied by investigating grilled chicken samples seasoned with four different marinades and grilled at temperatures of about 110, 170 and 220°C. The amounts of the heterocyclic amines 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline, 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline and 2-amino-1-methyl-6-phenylimidazo[4,5- b]pyridine were determined only in samples grilled at 220°C, using a gas chromatography-mass spectrometry technique with negative-ion chemical ionization. Sensory quality was determined using the extended ranking test method and the mutagenic activity using the Ames Salmonella assay. At 220°C one of the marinades decreased the mutagenic activity in the chicken samples compared with the unseasoned control or samples treated with the other marinades. Great variations, without any clear correlation with mutagenicity, were observed in the amounts of heterocyclic amines between chicken samples treated with the same or different marinades. At the grilling temperatures of 170°C and 110°C the mutagenic activities of the chicken samples were lower or they were non-mutagenic. There was no correlation between mutagenic activity and sensory quality of the products. The samples with high mutagenic activity were ranked to be as good as the samples with lower or no mutagenicity. The results show that it is possible to prepare grilled products with reduced mutagenicity without compromising their sensory quality. It was also evident that marinades can have a reducing effect on the mutagenicity of grilled chicken. Variation observed in the amounts of heterocyclic amines between equivalent products makes it difficult to estimate their concentration in everyday foods.

Influence of frying fat on the formation of heterocyclic amines in fried beefburgers and pan residues

The influence of six frying fats (butter, margarine, margarine fat phase, liquid margarine, rapeseed oil and sunflower seed oil) on the formation of mutagenic/carcinogenic heterocyclic amines (HAs) during the frying of beefburgers was investigated. Frying was performed at 165 and 200°C (i.e. under conditions that represented normal household cooking practices). The fried beefburgers and their corresponding pan residues were purified using solid-phase extraction and analysed for HAs using HPLC with photodiode array UV and fluorescence detection. The HAs 2-amino-3,8-dimethylimidazo[4,5- f]-quinoxaline (MelQx), 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline (DiMeIQx), 2-amino-1-methyl-6-phenylimidazo[4,5- b]pyridine (PhIP), 9H-pyrido[3,4- b]indole (norharman) and 1-methyl-9H-pyrido[3,4- b]indole (harman) were recovered. The amount increased with the temperature, and the content of HAs in the pan residue was much higher than in the corresponding beefburger. The amounts of MeIQx ranged from 0.2 to 1.6 ng/g in the beefburgers and from 0.8 to 4.3 ng/g in the pan residues. DiMeIQx ranged from undetectable to 0.4 ng/g in the beefburgers and from 0.4 to 1.3 ng/g in the residues. PhIP ranged from 0.08 to 1.5 ng/g in the meat and from 0.4 to 13.3 ng/g in the residues. The total amount of HAs in meat and pan residue combined was significantly lower after frying in sunflower seed oil or margarine than after frying with the other fats. The observed differences in MeIQx and DiMeIQx formation could be explained in terms of oxidation status (peroxide and anisidine value) and antioxidant content (vitamin A, vitamin E and tocopherols/tocotrienols) using partial least squares analysis.

Occurrence of mutagenic/carcinogenic heterocyclic amines in meat and fish products, including pan residues, prepared under domestic conditions.

Some typical Swedish meat and fish products, e.g. bacon, beefburgers, meatballs, Baltic herring, salmon, smoked fish, black pudding and sausages, and their corresponding pan residues, were analysed by HPLC for their content of mutagenic/carcinogenic heterocyclic amines (HAs). The products were cooked using recommended domestic cooking conditions concerning temperature, time and frying equipment. The amount of HAs was low in most products, though the amount was higher in the pan residues, especially in the pan residue from the frying of Falun sausage, which contained 18.5 ng HAs/g cooked product. Mostly MeIQx (2-amino-3,8-dimethylimidazo[4,5-f]-quinoxaline) and 4,8-DiMeIQx (2-amino-3,4,8-trimethylimidazo[4,5-f]-quinoxaline) were found, being 0.03-2.8 ng MeIQx/g and n.d.-3.4 ng 4,8-DiMeIQx/g cooked product in the food products and 0.05-7.3 ng MeIQx/g and n.d.-2.8 ng 4,8-DiMeIQx/g cooked product in the pan residues. High levels of IQ (2-amino-3-methylimidazo[4,5-f]quinoline), 10.5 ng/g, were only found in well-done bacon and a correlation was seen between fat content and IQ formation. Low levels of MeIQ (2-amino-3,4-dimethylimidazo[4,5-f]quinoline) and PhIP (2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine) were found in the foods.

Analysis of Mutagenic and Carcinogenic Compounds in Oil of Charred Egg Yolk

The mutagenic activities and the amounts of heterocyclic amines in oil of charred egg yolk were investigated in order to estimate the carcinogenic risk to humans.Fresh egg yolk was roasted at 300-350° for 30min to get a black and oily material. The mutagenic activity of this material to Salmonella typhimurium TA98 with S9mix was 24 revertants/mg. The mutagenic material was further purified by 2N hydrochloric acid-ethyl ether partition, followed by blue cotton treatment. The mutagenic activities after these purification steps were 5, 108 and 16, 435 revertants/mg, respectively.Mutagenic and carcinogenic heterocyclic amines in the partially purified material were analyzed by a combination of high performance liquid chromatography using octadecylsilane and cation exchange columns, and four carcinogenic heterocyclic amines, Trp-P-1, Trp-P-2, AαC and MeAαC were detected. The contents of these heterocyclic amines were as follows: 4.3ng of Trp-P-1, 1.0ng of Trp-P-2, 6.1ng of AαC and 1.2ng of McAαC per one gram of oil of charred egg yolk. These compounds were estimated to account for only one percent of the mutagenicity of oil of charred egg yolk.

Amounts of heterocyclic amines in basic fraction of cigarette smoke condensates

Amounts of heterocyclic amines in basic fraction of cigarette smoke condensates