Formation Of Heterocyclic Amines Research Articles

Unfiltered beer based marinades reduced exposure to carcinogens and suppressed conjugated fatty acid oxidation in grilled meats

Grilled meat consumption is associated with exposure to carcinogenic compounds and increased risk factors for cancers. We investigated the efficacy of novel formulations of unfiltered India session ale and Wheat ale based-marinades enhanced with antioxidant-rich herbs and spices to suppress formation of carcinogenic heterocyclic amines (HCAs) while protecting anticarcinogenic conjugated linoleic acids (CLAs) from lipid oxidation in grilled ruminant meats. Both formulations significantly enhanced the polyphenolic content of grilled beef by 54–71% and moose meat by 178–314% compared to their unmarinated controls. The antioxidant activities increased by 57–96% and 58–139% with concomitant suppression of total conjugated linoleic acid oxidation by 30–37% and 432% in grilled beef and moose meats respectively compared to their unmarinated counterparts. Furthermore, 88–97% of HCA suppression and 61–71% of CLAs retention came from phenolics in the marinades. This system could be useful for reducing the risk factors associated with red meat consumption while promoting health.

Effect of Creatine and Glucose on Formation of Heterocyclic Amines in Grilled Chicken Breasts.

The occurrence of heterocyclic amines (HAs) in grilled chicken breasts was investigated. All samples contained HAs, including MeIQx, PhIP, and the β-carbolines harman and norharman. In particular, PhIP was found in concentrations of 1.5–9.1 ng/g, and MeIQx was detected at very low concentrations (n.d.–1.1 ng/g). The concentrations of two co-mutagenic β-carbolines, harman and norharman, ranged from 0.8 to 2.3 ng/g when the content of the precursor glucose was varied from 100 to 620 mg/kg. In contrast, the content of the precursor creatine in non-grilled chicken breasts varied by only 8.6%. A significant linear correlation existed between the molar concentration of PhIP and the molar ratio of creatine/glucose (r = 0.88, p < 0.001). We, thus, conclude that the formation of PhIP may be inhibited with increasing concentrations of glucose in chicken breast. Chicken patties coated with ribose or glucose-containing water in oil emulsions confirmed that both reducing sugars decreased PhIP formation with the preferred concentrations (sensory analysis) of 0.5–1% for ribose and 1% for glucose leading to a reduction of PhIP formation by 28–34% and 39%, respectively.

Phytochemical-Rich Antioxidant Extracts of Vaccinium Vitis-idaea L. Leaves Inhibit the Formation of Toxic Maillard Reaction Products in Food Models.

Thermal treatment of proteinaceous foods generates heat-induced Maillard reaction substances including toxic advanced glycation end products (AGEs) and heterocyclic amines (HAs). It is known that plant phenolic compounds may influence Maillard reaction. This study investigated the impact of lingonberry leaf extracts on the formation of Nε -(carboxymethyl)lysine (CML) and Nε -(2-furoylmethyl)-L-lysine (furosine) in milk model system and HAs in meat-protein and meat model systems. In addition, lingonberry leaf extracts obtained by different solvents were characterized by radical scavenging, Folin-Ciocalteu assays and ultrahigh pressure liquid chromatography quadruple-time-of flight mass spectrometry (UPLC-qTOF-MS). Water extract (WE) stronger suppressed CML than furosine formation in milk model system: CML levels were reduced by nearly 40%. Moreover, quinic acid and catechin, which were abundant in WE, were effective in inhibiting CML and furosine formation. WE and acetone extract (AE) at 10 mg/mL significantly inhibited HAs formation in both model systems. However, higher suppressing effect on HAs formation showed AE, which had lower antioxidant capacity and total phenolic content values than WE. WE contained higher amounts of hydroxycinnamic acids, proanthocyanidins and flavonols, while AE was richer in flavan-3-ols and arbutin derivatives. It indicates that the composition of phenolics might be a major factor for explaining different effect of extracts from the same plant on HAs formation. In general, the results suggest that lingonberry leaves is a promising source of phytochemicals for inhibiting toxic Maillard reaction products and enriching foods with plant bioactive compounds. PRACTICAL APPLICATION: The increased consumption in processed foods has been linked with the increased risks of various diseases, while thermal food processing is required to develop flavor, insure safety, and extend shelf life. Therefore, developing effective technological means for inhibiting the formation of heat-induced toxic substances is an important task. This study showed a potential of lingonberry leaf extracts containing health beneficial phytochemicals to suppress the formation of toxic Maillard reaction products during heating of milk and meat.

Mechanistic formation of hazardous molecular heterocyclic amines from high temperature pyrolysis of model biomass materials: cellulose and tyrosine

BackgroundResearch inventories on the co-pyrolysis of major biomass components such as cellulose with amino acid materials is scarce in literature despite the fact that such studies are critical in understanding toxic product relations from high temperature cooking, combustion of bio-fuels, cigarette smoking and forest fires. This paper explores, quantitatively, the yields of heterocyclic nitrogenated molecular reaction products of grave mutagenetic concern from the co-pyrolysis of model biomass materials; tyrosine and cellulose. Research has established that heterocyclic amines such as isocyanates are mutagens as well precursors for asthma, and other respiratory disorders.MethodsAn equimassic mixture of tyrosine and cellulose (50 ± 2 mg) by weight were pyrolyzed in a tubular quartz reactor in flowing nitrogen at 1 atm. Besides, varying combinations of tyrosine and cellulose in the ratios 3:1 and 1:3 were also explored for comparison. The reaction time was set at 2 s so as to simulate combustions events in nature. The pyrolysate was collected over 5 mL dichloromethane and characterized using a gas chromatograph coupled to a mass spectrometer detector.ResultsEvidently, it was noted that 1-methylindazole was released in high yields at 300 °C, constituting ~ 300 µg in the entire pyrolysis temperature range (200–700 °C). Nonetheless, isoindazole gave the highest yield ~ 730 µg while 1-naphthyl isocyanate gave a total yield of ~ 336 µg in the same temperature range. Remarkably, the change in char yield between 300 and 450 °C for the pyrolysis of 25% tyrosine in 75% cellulose was found to be ~ 48% whereas the change in char yield for the pyrolysis of 75% tyrosine in 25% cellulose was 49%.ConclusionThe char and tar yields considered important residues of biomass burning have been reported in this study and found to be consistent with other research output in literature. The striking similarities of % yield of char across all temperatures for various combinations was the most significant observation in this investigation—char yield was independent of the mixing ratio during pyrolysis. From a mechanistic standpoint, it was noted that tyrosine inhibited cellulose based nitrogenated products. Thus N-products dominated the O-products.

Frying oils with lower levels of saturated fatty acids induce less heterocyclic amine formation in meat floss (boiled, shredded and fried pork)

SummaryHeterocyclic amines (HAs) as potent mutagens are formed in meat floss which is a boiled, shredded and fried traditional meat product. In this study, effects of frying oils (lard, soybean oil and palm oil) on the formation of HAs in meat floss during frying have been investigated. The results showed that the contents of Norharman, Harman, AαC and MeAαC in meat floss that treated with lard and palm oil were higher than soybean oil which contained less saturated fatty acids (P &lt; 0.05). The contents of total HAs in meat floss that treated with palm oil at 150 °C and 180 °C were significantly higher than that treated with soybean oil and lard (P &lt; 0.05). In conclusion, meat floss treated with soybean oil at 120 °C, 150 °C and 180 °C contained lowest levels of HAs and soybean oil could be used as lard substitution to produce healthy meat floss.

Novel unfiltered beer-based marinades to improve the nutritional quality, safety, and sensory perception of grilled ruminant meats

Ruminant meat is considered an excellent source of proteins, dietary fatty acids and essential minerals. Grilling is a popular cooking method; however, the high temperatures employ could modify the grilled meat quality and safety. In this study, the effects of novel beer-based marinades infused with herbs and spices on the quality, safety, and sensory perception of grilled beef and moose meat is examined. Unmarinated meat showed high content of volatile lipid oxidation and Maillard reaction products compared to the marinated samples, which contained higher number and abundance of terpenes and sulfur based compounds. Strong relationships between Maillard products and heterocyclic amines formation, as well as between volatile terpenes and the lipophilic antioxidant activity, were observed in the grilled meats. The findings suggest the unfiltered beer-based marinades were effective in reducing lipid oxidation and Maillard reaction compounds formation, while improving the nutritional quality, safety and sensory preference of grilled ruminant meats.

Cooking with elaborate recipes can reduce the formation of mutagenic heterocyclic amines and promote co-mutagenic amines

ABSTRACTHeterocyclic amines (HCAs) are foodborne carcinogens for which their formation is highly dependent on cooking conditions. HCAs have been commonly quantified in food items prepared with simple procedures. This approach is suitable for elucidating HCAs’ formation, but it only partially reflects the contamination in consumed food. In the current investigation, the generation of HCAs has been investigated in fried beef items prepared with elaborated cooking recipes, and their occurrence has been compared with control beef fried without the addition of ingredients other than oil. The food recipes that included a variety of food ingredients had lower yields of mutagenic HCAs (≥47% reduction, with individual HCA levels ranging between 0.01 and 2.22 ng/g) with respect to the control beef. In contrast, the co-mutagens norharman and harman were formed generally at greater levels (up to three times the contamination in the control fried beef) in the items prepared including a greater variety of ingredients.

Rapid determination of heterocyclic amines in ruminant meats using accelerated solvent extraction and ultra-high performance liquid chromatograph–mass spectrometry

Cooking techniques such as grilling confer several benefits to meat during food preparation including improved palatability, digestibility, preservation, and safety, as well as enhancing the sensory characteristics and net nutritional gain. However, grilling can lead to the formation of harmful compounds such heterocyclic amines (HCAs). HCAs are potent carcinogenic and mutagenic nitrogen containing compounds produced during certain cooking conditions of protein rich foods. Dietary intake of HCAs is associated with increased risk factors for cancers in humans. As such, there is overwhelming interest in identifying improved methods for rapid and accurate determination of heterocyclic amines in food matrices that is sensitive and avoids exhaustive sample preparation steps. Herein, we describe an approach that involves first extracting HCAs by pressurized accelerated solvent extractor using methanol as solvent, followed by addition of internal standard and quantification of HCAs by ultra-high performance liquid chromatography-high resolution accurate mass spectrometric detection (UHPLC-HRAMS). This method is fast, accurate, reproducible and does not require exhaustive sample pre-treatments prior to UHPLC-HRAMS analysis compared to existing/traditional methods for HCA analysis.•The method is automated, fast and uses tunable pressurized liquid extractor to selectively extract HCAs•Method does not require exhaustive cleanup and preconcentration steps prior to UHPLC/HRAMS analysis of HCAs•Validation showed method to be accurate, precise, and useful for routine multi-sample HCA analyses

Lactobacillus casei expressing methylglyoxal synthase causes browning and heterocyclic amine formation in Parmesan cheese extract

Undesired browning of Parmesan cheese can occur during the latter period of ripening and cold storage despite the relative absence of reducing sugars and high temperatures typically associated with Maillard browning. Highly reactive α-dicarbonyls such as methylglyoxal (MG) are products and accelerants of Maillard browning chemistry and can result from the microbial metabolism of sugars and AA by lactic acid bacteria. We demonstrate the effects of microbially produced MG in a model Parmesan cheese extract using a strain of Lactobacillus casei 12A engineered for inducible overexpression of MG synthase (mgsA) from Thermoanaerobacterium thermosaccharolyticum HG-8. Maximum induction of plasmid-born mgsA led to 1.6 mM MG formation in Parmesan cheese extract and its distinct discoloration. The accumulation of heterocyclic amines including β-carboline derivatives arising from mgsA expression were determined by mass spectrometry. Potential MG-contributing reaction mechanisms for the formation of heterocyclic amines are proposed. These findings implicate nonstarter lactic acid bacteria may cause browning and influence nutritional aspects of Parmesan by enzymatic conversion of triosephosphates to MG. Moreover, these findings indicate that the microbial production of MG can lead to the formation of late-stage Maillard reaction products such as melanoidin and β-carbolines, effectively circumventing the thermal requirement of the early- and intermediate- stage Maillard reaction. Therefore, the identification and control of offending microbiota may prevent late-stage browning of Parmesan. The gene mgsA may serve as a genetic biomarker for cheeses with a propensity to undergo MG-mediated browning.

Effects of smoking or baking procedures during sausage processing on the formation of heterocyclic amines measured using UPLC-MS/MS

We used an UPLC-MS/MS method to investigate the effects of smoking or baking on the formation of heterocyclic amines (HAs) in sausage processing. We used principal component analysis (PCA) to differentiate the chemical composition, pH and colour of the processed sausages. We detected and quantified eight types of HAs (PhIP, DMIP, Phe-P-1, IQ[4,5-b], 7,8-DiMeIQx, AαC, harman and norharman) in sausages, finding total HA concentrations as high as 422 ± 17.5 ng/g. Higher smoking temperatures led to higher concentrations of total HA in smoked sausages (330 ± 8.19 to 422 ± 17.5 ng/g). On the contrary, higher baking temperatures created lower total HA concentrations in baked sausages (ranging from 139 ± 9.83 to 306 ± 0.92 ng/g). Our results demonstrated that HAs are produced even at low temperatures, which means that HAs should be controlled during sausage processing to minimise their formation.

Inhibitory effect of Chrysanthemum morifolium flower extract on the formation of heterocyclic amines in goat meat patties cooked by various cooking methods and temperatures

The effect of Chrysanthemum morifolium flower extract (CME) was investigated on the formation of heterocyclic amines (HCAs) in goat meat patties cooked at different temperatures by different cooking methods. In patties without CME, the level of total HCAs increased analogously with the increase in cooking temperature. The inhibitory effect of CME on HCAs ranged from 14% to 82%. The total HCAs content were reduced by 46%, 40% and 35% in pan fried, deep fat fried and oven roasted goat meat patties, respectively, at 175 °C. While, at 225 °C, the amount of total HCAs was decreased by 52%, 47% and 32% in deep fat fried, pan fried and oven roasted patties respectively, whereas, in barbecue patties the reduction was 36%. Hence, it is concluded that the effect of CME was more prominent in deep fat frying and pan frying cooking methods and increase in temperature enhance the efficacy of CME in both cooking methods.

Inhibitory effect of mixture herbs/spices on formation of heterocyclic amines and mutagenic activity of grilled beef

ABSTRACTNatural antioxidants in spices and herbs have attracted considerable attention as potential inhibitors against the formation of mutagenic heterocyclic amines (HCAs) in heat-processed meat. In this study, the inhibitory activity of four spices/herbs and their mixtures on HCAs formation in grilled beef were examined. A simplex centroid mixture design with four components comprising turmeric, curry leaf, torch ginger and lemon grass in 19 different proportions were applied on beef samples before grilling at 240 ºC for 10 min. The HCAs were extracted from the samples using solid phase extraction (SPE) method and analysed using Liquid chromatography mass spectrometry LC-MS/MS. All spices/herbs in single or mixture forms were found to reduce total HCA concentrations in marinated grilled beef ranging from 21.2% for beef marinated with curry leaf to 94.7% for the combination of turmeric and lemon grass (50:50 w/w). At the optimum marinade formula (turmeric: lemon grass 52.4%: 47.6%), concentration of 2-amino-3-methylimidazo[4,5-f]quinolone (IQ), 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), Harman, Norharman and AαC were 2.2, 1.4, 0.5, 2.8 and 1.2 ng/g, respectively. The results of the mutagenic activity demonstrated that this optimised marinade formula significantly (p < 0.05) diminished mutagenicity of marinated grilled beef in bacterial Ames test.

The effect of common spices and meat type on the formation of heterocyclic amines and polycyclic aromatic hydrocarbons in deep-fried meatballs

Spices are commonly used as flavour enhancer and natural antioxidants in processed meat products. However, effect of spices on the formation of carcinogens especially heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs) in different meat system has yet been investigated. In this study, 0.5% garlic, onion, red chilli, paprika, ginger and black pepper powder was added into beef and chicken meatballs fried at 180 °C. Formation of HCAs and PAHs was examined to evaluate the inhibitory efficiency of spices in beef and chicken meatballs. Control meatballs (without adding spice) contained the highest amount of HCAs compared with all spice added meatballs of both beef and chicken. All the spices powder reduced the formation of total HCAs, while ginger powder achieved the highest inhibition efficiency compared with all other spices. The correlation coefficient (r) between antioxidant capacity of spices and total HCAs was - 0.853 (p < 0.01) for TEAC and −0.712 (p < 0.05) for ORAC. Chicken meatballs contained less HCAs than beef, but no difference was observed in total PAHs between beef and chicken meatballs (p > 0.05). Both electron transfer and hydrogen donation were involved with the inhibitory effect of spices for developing HCAs, but only electron transfer mainly in the formation of PAHs. In conclusion, antioxidant capacity of spices determined their efficiency in prohibiting formation of HCAs and PAHs, and meat type affected the formation of HCAs, but not PAHs.

Effects of different types of soy sauce on the formation of heterocyclic amines in roasted chicken

ABSTRACTThe objective of the study was to determine the effect of different types of soy sauce and marinating time on the formation of heterocyclic amines (HCAs) in roasted chicken. Chicken breast samples were marinated with sweet, salty, light and dark soy sauce at 0, 3, 6 and 12 h (control treatment was the chicken without marinade). The concentrations of free amino acids, sugars and creatinine were determined before roasting while HCA concentrations were determined after roasting. All types of soy sauce significantly increased (p ≤ 0.05) the concentration of HCAs in roasted chicken with increasing marinating time. The highest increment of total concentration of HCAs was found in samples marinated with light soy sauce (887%) followed by dark (375%), salty (193%) and sweet (169%) at 12 h. PhIP (2-amino-1-methyl-6-phenylimidazo(4,5-b)pyridine) showed a substantial reduction in samples only momentarily marinated with sweet, salty and dark soy sauce (0 h). Free amino acids were found to be more strongly correlated with the formation of HCAs than reducing sugars or creatinine.

Effect of organic acid ingredients in marinades containing different types of sugar on the formation of heterocyclic amines in grilled chicken

The aim of the study was to determine the use of alternative organic acids in formulating marinade ingredients to reduce heterocyclic amines (HCA) in grilled chicken (satay). Samples were marinated with table sugar, brown sugar, and honey with the addition of tamarind, lemon, lime, and calamansi for 24 h at 4 °C. The pH readings before and after marinating were measured. HCA concentrations before and after grilling were quantified. There was a significant difference (p<0.05) in the combined HCAs among the control and marinated grilled chickens. Using lemon in marinades containing table sugar, concentrations of DiMeIQx were significantly reduced (p < 0.006) from 16.5 ng/g (low) to 8.30 ng/g for (high) concentrations of organic acid ingredients. The mean pH of the treated samples was significantly lower (p<0.05) than in the control samples. Calamansi was found to reduce HCAs in marinades containing table sugar and brown sugar, whereas tamarind in marinades containing honey.

UPLC-MS/MS and multivariate analysis of inhibition of heterocyclic amine profiles by black pepper and piperine in roast beef patties

In this study, UPLC-MS/MS combined with principal component analysis (PCA) with the help of scores, loadings, and contribution plots was used to investigate the inhibition of the profiles of carcinogenic and mutagenic heterocyclic amines (HAs) in roast beef patties by different levels of black pepper (0.05, 0.10, and 0.15%, g/g) or piperine (0.005, 0.010, and 0.015%, g/g). Six HAs from three categories, imidazopyridine (PhIP), imidazoquinoxaline (IQx, MeIQx, and 4,8-DiMeIQx), and β-carboline (harman and norharman), were detected and quantified in the roast beef patties. The PCA results demonstrated that both black pepper and piperine can significantly suppress the HA profiles and that lower levels of black pepper or piperine lead to better inhibition of HA formation, except the HA profiles of beef patties with 0.005% and 0.01% piperine were similar. In comparison, piperine inhibited HA formation better than did black pepper for all six HAs, as shown by the contribution plot. The total HAs were inhibited by all levels of black pepper (42%, 34%, 25%) and piperine (62%, 60%, 56%) in a dose-dependent manner, although black pepper suppressed only PhIP, IQx, MeIQx, and 4,8-DiMeIQx, whereas piperine inhibited all six HAs. The results show that UPLC-MS/MS in conjunction with PCA is a powerful tool for screening the inhibitory effects of spices and their components along with their relationship to HAs and can thus be used for safety control in food processing procedures.

Inhibitory effects of Sichuan pepper (Zanthoxylum bungeanum) and sanshoamide extract on heterocyclic amine formation in grilled ground beef patties

This study evaluated the inhibitory effects of Sichuan pepper (Zanthoxylum bungeanum) and sanshoamide extract on the formation of heterocyclic amines (HAs) in grilled beef patties. The following major HAs were detected and quantified: imidazopyridine (2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine, PhIP), imidazoquinoxalines (2-amino-3-methyl-3H-imidazo[4,5-f]quinoxaline, IQx; 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline, MeIOx; 2-amino-3,4,8-trimethyl-3H-imidazo[4,5-f]quinoxaline, 4,8-DiMeIQx) and β-carbolines (9H-pyrido[3,4-b]indole, norharman; 1-methyl-9H-pyrido[3,4-b]indole, harman). The rates of PhIP, IQx, MeIQx and 4,8-DiMeIQx were inhibited significantly by 82%, 61%, 28% and 79%, respectively, in patties treated with a low-concentration of pepper (0.5%), and by 27%, 45%, 44% and 26%, respectively, following treatment with a low-concentration sanshoamide extract (0.005%). All inhibition rates exceeded 70% at pepper and sanshoamide extract concentrations of 1.0% and 0.010%, respectively. Harman and norharman could be significantly (p<0.05) enhanced by the addition of all concentrations of Sichuan pepper, however, sanshoamide extract had no significant (p>0.05) effect on them, although 0.005% of the extract could slightly increase the formation of them. Notably, significant correlations were observed between the HA inhibition rates and pepper or sanshoamide extract concentrations, especially for PhIP (r=0.87, p=2.30E−3), IQx (r=0.99, p=5.04E−7) and 4,8-DiMeIQx (r=0.88, p=1.96E−3). These results indicate that Sichuan pepper and sanshoamide extract could inhibit the formation of carcinogenic HAs during thermal preparation of protein-rich foods, and therefore might reduce the risk of chronic diseases associated with the long-term intake of HA-containing food products.

Vegetable oil as fat replacer inhibits formation of heterocyclic amines and polycyclic aromatic hydrocarbons in reduced fat pork patties

Formation of heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs) was examined to evaluate the impact of using vegetable oil as fat replacement on carcinogen formation in meat product. Pork patties were formulated with 40% fat replacement by olive oil, sunflower oil or grape seed oil, respectively and cooked at 180 °C or 220 °C. Control patties contained the highest amount of HCAs compared with all other patties at both temperatures. Olive oil and sunflower oil replacement completely inhibited formation of MeIQ (2-amino-3, 4-dimethylimidazo[4,5-f]quinoline), while grape seed oil completely inhibited MeIQx (2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline), 4,8-DiMeIQx (2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline) and PhIP (2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine) in patties. Grape seed oil achieved the highest inhibition capacity compared with sunflower oil and olive oil. HCAs increased significantly with cooking temperature (p < 0.05), but no difference was observed in total PAHs for patties cooked at different temperature (p > 0.05). In conclusion, fat replacement with sunflower oil, olive oil or grape seed oil in pork patties could reduce the formation of HCAs without compromising eating quality.

Inhibitory effect of cellulose fibers on the formation of heterocyclic aromatic amines in grilled beef patties.

Microcrystalline cellulose (MCC) or carboxymethyl cellulose (CMC) can be used as fat replacers; both are nondigestible fibers. As water-holding compounds, the impact of added CMC or MCC was studied concerning the formation of heterocyclic amines (HAAs). Low-fat patties with 0.5-3% MCC/CMC were prepared using 90% of beef and 10% of an aqueous fiber dispersion and were determined for HAA-levels after grilling. The HAAs in patties containing CMC(MCC) were found in the following concentrations; MeIQx (2-Amino-3,8-dimethylimidazo[4,5-f]quinoxaline) 0.6-2.7 (0.9-3.3)ng/g, 4,8-DiMeIQx (2-Amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline) n.d.-1.5 (n.d.-2.2)ng/g and PhIP (2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine) 0.03-0.3 (0.06-0.2)ng/g. The patties clearly contained lower HAA-levels with increasing addition of CMC or MCC. A continuous increase of the concentrations of comutagenic harman was observed (CMC: 1.2-13.2; MCC: 5.2-11.4ng/g) for increasing levels of fibers and a slight decrease of the content of norharman for MCC (0.5-1.6ng/g). No clear tendency was found for norharman using CMC (0.3-1.1ng/g).

Inhibitory profiles of chilli pepper and capsaicin on heterocyclic amine formation in roast beef patties.

The inhibitory profiles of chilli pepper and capsaicin, as well as their relationship to the formation of heterocyclic amines (HAs) in roast beef patties were investigated using ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) combined with principal component analysis (PCA). HAs including 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), 2-amino-1,6-dimethylimidazo[4,5-b]pyridine (DMIP), 2-amino-1,5,6-trimethylimidazo[4,5-b]pyridine (1,5,6-TMIP), 2-amino-3-methyl-3H-imidazo[4,5-f]quinoxaline (IQx), 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), 2-amino-3,4,8-trimethyl-3H-imidazo[4,5-f]quinoxaline (4,8-DiMeIQx), 1-methyl-9H-pyrido[3,4-b]indole (harman) and 9H-pyrido[3,4-b]indole (norharman) were detected and quantified in beef patties. Different levels of chilli pepper and capsaicin had different inhibitory profiles on HA formation, but had no significant (P>0.05) effect on the texture of the patties. Furthermore, all levels of chilli pepper and capsaicin reduced total HA and PhIP concentrations dose-dependently, with the highest inhibitions of 80% and 98% at 2mg of capsaicin. Moreover, capsaicin inhibited all HAs more than chilli pepper, implying that ingredients other than capsaicin in chilli pepper may promote the formation of HAs. These results could be useful for the reduction of HA, during food processing procedures, by spices.