Comparative analysis of charcoal grilling,infrared grilling and superheated steam roasting on the colour,textural quality and heterocyclic aromatic amines of lamb patties

The colour, textural profile and heterocyclic aromatic amines content of lamb patties cooked by charcoal grilling, infrared grilling and superheated steam roasting were investigated. The results of colour showed that lightness and yellowness values were highest in the superheated steam and lowest in charcoal grilled patties. The texture characteristics observed in the superheated steam, and infrared patties were much better. Water loss was highest in charcoal grilled meat. Charcoal grilling produced a significantly (P < 0.05) much higher amount of total HAAs, ranging from 171.26 ng g⁻¹ to 555.29 ng g⁻¹ (polar) and from 200.77 ng g⁻¹ to 426.07 ng g⁻¹ (non-polar) HAAs, than infrared (39.21 ng g⁻¹ −181.37 ng g⁻¹⁾ and (52.84 ng g⁻¹ −148.59 ng g⁻¹) and superheated steam roasting (from 8.67 ng g⁻¹ to 30.66 ng g⁻¹ and from 23.61 ng g⁻¹ to 89.66 ng g⁻¹⁾ for both types of HAAs in lamb patties. Colour, texture and HAAs were significantly influenced by time and by the temperature used for each cooking method.     

The assessment of commercial beef and chicken bouillons in terms of heterocyclic aromatic amines and some of their precursors

Herein, the assessment of commercial beef and chicken bouillons in terms of heterocyclic aromatic amines (HAAs) and some of their precursors was evaluated. Creatine and creatinine levels were ranged between 0.57–0.80 and 0.28–0.94 mg g⁻¹, respectively. Glutamic acid was found to be the most abundant amino acid in both bouillons. 2-amino-3,7,8-trimethylimidazo[4,5-ƒ]quinoxaline (7,8-DiMeIQx, up to 0.03 ng g⁻¹) was the only quantified analyte in beef bouillons, whereas it (up to 0.08 ng g⁻¹) was determined in addition to 2-amino-3-methylimidazo[4,5-ƒ]quinoxaline (IQx, up to 0.08 ng g⁻¹) in chicken bouillons. Creatine, creatinine and free amino acid composition did not have the capacity to initiate the formation of HAAs. Therefore, bouillons do not pose risk in terms of HAAs. However, it should be noted that multiple factors, such as the substrate amount and production conditions, may affect the results. Glutamic acid content is remarkable in commercial bouillons sold in Turkey.     

Effects of breeds on the formation of heterocyclic aromatic amines in smoked lamb

Heterocyclic aromatic amines (HAAs) are mutagenic and carcinogenic compounds, which are commonly detectable in cooked meat products. The objective of this study was to evaluate the effect of sheep breeds on the formation of HAAs in smoking cooked lamb. The results showed that HAAs in smoked lamb meat products were generally low (2.74–5.42 ng g^?1), with most being Harman and Norharman. IQ, MeIQx, 4,8‐DiMeIQx, Trp‐p‐2, PhIP and MeAaC were not detected in smoked lamb meat products in the present study. The total content of HAAs differed between meat products of different sheep breeds, but no difference in the order of magnitude was determined. Smoking altered the content of protein, fat, moisture and free amino acids in lamb meat products, which was probably mostly contributed by the reduction in meat moisture. Free tryptophan decreased in all breeds after smoking, which was probably used to synthesise HAAs. In summary, HAAs were low in smoked lamb meat products of all sheep breeds; thus, consumption of smoked lamb meat products should contribute very limited intake of HAAs.     

Impact of tarragon usage on lipid oxidation and heterocyclic aromatic amine formation in meatball

Herein, the effects of tarragon on lipid oxidation and heterocyclic aromatic amines (HAAs) formation in meatballs were determined. A significant (P < 0.05) reduction in pH and TBARS values of the meatballs with tarragon was determined, while no significant effect (P > 0.05) was observed regarding water content of the samples. Only 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ) compound (up to 0.06 ng g⁻¹) was detected in the control group meatballs. On the other hand, in the meatballs with tarragon, no HAAs could be detected. Tarragon use completely inhibited the formation of MeIQ. The total HAA content of the samples in the control group increased with increasing the cooking temperature. The total HAA contents of the control group meatballs changed between not detected and 0.06 ng g⁻¹. In conclusion, it can be recommended to use tarragon in meatball production as it completely inhibits the HAA formation and reduces TBARS value compared to the control group meatballs.     

Reduction of the polycyclic aromatic hydrocarbon (PAH) content of charcoal smoke during grilling by charcoal preparation using high carbonisation and a preheating step

Charcoal-grilling may lead to contamination of food with carcinogenic polycyclic aromatic hydrocarbons (PAHs) during the grilling process. The objective of this work was to determine the effect of charcoal preparation on 16 USEPA priority PAHs in the smoke produced during the grilling process. Firstly, mangrove charcoal was prepared at carbonisation temperatures of 500, 750 and 1000°C. The charcoal were then preheated by burning at 650°C. This preheating step is usually used to prepare hot charcoal for the grilling process in the food industry. In this study, charcoal was preheated at different burning times at 5, 20 min and 5 h, at which time partial and whole charcoal glowed, and charcoal was completely burnt, respectively. Finally, PAHs in the smoke were collected and determined by GC/MS. The result showed that charcoal prepared at a carbonisation temperature of 500°C had higher levels of PAHs released into the smoke. In contrast, charcoal produced at 750 and 1000°C had lower PAHs released for all burning times. In addition, PAHs released for 5, 20 min and 5 h of burning time were about 19.9, 1.2 and 0.7 µg g^?1 dry charcoal for charcoal produced at 500°C, and about 0.9–1.4, 0.8–1.2 and 0.15–0.3 µg g^?1 dry charcoal for charcoal produced at 750 and 1000°C, respectively. Therefore, this research suggests that food grilled using charcoal carbonised at a high temperature of about 750°C presents a lower risk of PAH contamination. In addition, in the preheating step, whole charcoal should fully glow in order to reduce the PAH content in charcoal before grilling.     

Influence of smoking parameters on the concentration of polycyclic aromatic hydrocarbons (PAHs) in Danish smoked fish

A new method for the analysis of 25 polycyclic aromatic hydrocarbon (PAH) compounds in fish was developed, validated, and used for the quantification of PAHs in 180 industrially smoked fish products. The method included pressurized liquid extraction, gel-permeation chromatography (Bio-beads S-X3), solid-phase extraction (silica gel), and gas chromatography-mass spectrometry analysis. The sum concentration of 25 PAHs (∑PAH₂₅) was highest in smoked herring (n = 3) and mackerel fillets (n = 13), with an average concentration of 320 and 235 µg kg^?1, respectively. Lowest average ∑PAH₂₅ concentrations were obtained for indirectly smoked trout (26 µg kg^?1). Principal component analysis was used to correlate processing parameters to PAH concentrations and to identify the effects of these parameters. The analysis showed that for salmon hot-smoking conditions lead to higher ΣPAH₂₅ than cold smoking, and for other fish species direct smoking leads to higher ΣPAH₂₅ than indirect smoking. Also, the usage of common alder increases the PAH contamination compared with beech. The effects of smoking time, combustion temperatures, and two types of smoke-generating material on the ∑PAH₂₅ were also tested in a pilot plant study with smoked trout as a model fish. In addition to confirming that increased combustion temperatures and usage of common alder in comparison with beech increased ∑PAH₂₅, it was also revealed that the PAH concentration decreased in the order fish skin ? outer layer of the fish muscle > inner part of the fish muscle.     

Effect of cooking methods on the formation of heterocyclic aromatic amines in chicken and duck breast

Heterocyclic aromatic amines (HAAs), potent mutagens/carcinogens, are pyrolysis formed during the cooking of meat and fish. In the present study, the effects of various cooking methods, pan-frying, deep-frying, charcoal grilling and roasting on the formation of HAAs in chicken breast and duck breast were studied. The various HAAs formed during cooking were isolated by solid-phase extraction and analyzed by high-performance liquid chromatography (HPLC). Results showed that chicken breast cooked by charcoal grilling contained the highest content of total HAAs, as high as 112 ng/g, followed by pan-fried duck breast (53.3 ng/g), charcoal grilled duck breast (32 ng/g), pan-fried chicken breast (27.4 ng/g), deep-fried chicken breast (21.3 ng/g), deep-fried duck breast (14 ng/g), roasted duck breast (7 ng/g) and roasted chicken breast (4 ng/g). For individual HAA, the most abundant HAA was 9H-pyrido-[4,3-b]indole (Norharman), which was detected in charcoal grilled chicken breast at content as high as 32.2 ng/g, followed by 1-methyl-9H-pyrido[4,3-b] indole (Harman) and 2-amino-1-methyl-6-phenylimidazo[4,5-f]pyridine(PhIP) at 32 and 31.1 ng/g in charcoal grilled chicken breast, respectively. The content of PhIP in pan-fried duck and chicken breast were 22 and 18.3 ng/g, respectively. Generally, the type and content of HAAs in cooked poultry meat varies with cooking method and cooking conditions.     

Determination of polycyclic aromatic hydrocarbons (PAHs) in commonly consumed Nigerian smoked/grilled fish and meat

Smoking and/or grilling, when carried out with traditional methods involving direct contact with wood combustion fumes, is responsible for high contamination levels with carcinogenic polycyclic aromatic hydrocarbons (PAHs). The aim of this work was to investigate the PAH content of different smoked or grilled meat and fish products commonly consumed in Nigeria. A rapid method involving microwave-assisted saponification and simultaneous extraction followed by solid-phase extraction (SPE), high-performance liquid chromatography (HPLC) separation and spectrofluorometric detection was employed. Samples that were smoked or grilled using traditional systems, which use a wood fire, were heavily contaminated with benzo[a]pyrene (BaP) at levels ranging from 2.4 to 31.2 µg kg^?1 wet weight. Considerably lower contamination levels were found in samples smoked or grilled in the laboratory using a charcoal fire (BaP from 0.7 to 2.8 µg kg^?1 wet weight). The health risk associated with a daily consumption of 100 g of these products was also evaluated using the margin of exposure (MOE) approach. MOE values lower than 10,000 were obtained for all smoked/grilled commercial samples, indicating a potential concern for consumer health.     

Effects of cooking methods and levels on formation of heterocyclic aromatic amines in chicken and fish with Oasis extraction method

Heterocyclic aromatic amines (HCAs) are potent mutagenic and carcinogenic compounds formed during heat processing of proteinaceous food such as beef, poultry, and fish. The objective of this study was to measure nine HCAs in chicken chops and fish fillets cooked by various methods (microwave, oven, hot plate, pan-frying, and barbecuing) to different degrees of doneness (rare, medium, well done, and very well done). Total HCA amount in chicken changed between 0.24 and 8.21 ng/g, and not only the highest total amount but also the lowest total HCA amount was found in microwave cooked chicken samples. The highest total HCA amount found in fish for microwave, oven, hot plate, pan-frying, and barbecuing were 18.09, 4.28, 3.12, 6.98, and 5.22 ng/g, respectively. The results show that microwave cooking alone is found to possess the highest total HCA amount, followed by pan-frying, and barbecuing of meat samples, and the total HCA amount in cooked samples is low if cooked to rare and medium degrees of doneness. 2-amino-1-methyl-6-phenylimidazo[4,5-b] pyridine (PhIP), 2-amino-9H-pyrido[2,3-b]indole (AαC), and 2-amino-3-methyl-9H-pyrido[2,3-b]indole (MeAαC) were not detected in any samples.     

Effects of cooking methods on the formation of heterocyclic aromatic amines of two different species trout

Heterocyclic aromatic amines (HAAs) are sometimes formed in meats and fish cooked at high temperatures. In the present study, the effects of cooking methods by deep-fat frying, pan-frying, grilling and barbecuing on the formation of HAAs of fillets of rainbow trout (Oncorhynchus mykiss) and brown trout (Salmo trutta fario) were investigated. Barbecued brown trout (1 g) was estimated to contain 0.12 ng of IQ (2-amino-3-methylimidazo[4,5-f]quinoline), 0.02 ng 4,8-DiMeIQx (2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline). Grilled rainbow trout (1 g) was estimated to contain 0.02 ng 4,8-DiMeIQx. MeIQ (2-amino-3,4-dimethylimidazo[4,5-f]quinoline), MeIQx (2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline) and PhIP (2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine) were not detectable in all cooked fish.     

Determination of polycyclic aromatic hydrocarbons in edible oils and barbecued food by HPLC/UV–Vis detection

Determination of nine polycyclic aromatic hydrocarbons in corn, sunflower, olive oils and barbecued meat and fish by HPLC/UV–Vis method is described. The extraction procedure included a saponification, liquid–liquid extraction and finally purification of PAHs through a house-made silica–alumina column. Chromatographic determination was based on separation of PAHs on ODS column and measurement at 254 nm. All polycyclic aromatic hydrocarbons were separated and analyzed in 12 min on reversed phase ODS column with acetonitrile/water mobile phase at 1.5 mL min⁻¹ flow rate. The detection limits of nine polycyclic aromatic hydrocarbons ranged from 0.26 to 1.15 μg L⁻¹ at a signal/noise ratio of 3. The linearity of the method was between 0.9951 and 0.9996. Oil samples contain different PAHs ranging from 0.44 to 98.92 μg L⁻¹. Barbecuing process increased the concentration (in the range of 2- to 8-fold) and caused the formation of PAHs in food samples.     

Determination of four priority polycyclic aromatic hydrocarbons (4PAHs) by GC-MS in traditional Turkish yoghurts

ABSTRACT

Polycyclic aromatic hydrocarbons (PAHs) are ingested with foods and cause toxicities for humans. Yoghurt is one of the main foods that mediate PAH ingestion. Yan?k yoghurt, a traditional strained yoghurt, can contain PAHs due to its production process. Therefore, the concentration and types of four polycyclic aromatic hydrocarbons were determined by gas chromatography-mass spectrometry (GC-MS). Yan?k yoghurt samples were collected from different shops in Denizli, Turkey. For the method validation, the Eurachem guide (second edition) was adopted. Accordingly, linearity, working range, limits of detection (LOD), quantification (LOQ), precision and trueness values were set. Due to the selected validation parameters, the limit for detection was between 0.03 ng g^?1and 0.05 ng g^?1while the limit for quantification was between 0.10 ng g^?1 and 0.16 ng g^?1. Recovery rates higher than 83.80 % were obtained for four PAHs at two spiked concentrations (2.0 and 5.0 ng g^?1). Five Yan?k yoghurt samples and one commercial concentrated yoghurt sample were successfully analysed using the validated method.     

Physicochemical traits and sensory quality of commercial butter produced in the Azores

In the volcanic islands of the Azores archipelago, pasture is available the entire year and affects the composition of bovine milk fat. The composition of cows' milk butter manufactured in this region was evaluated. All brands showed excellent microbiological and oxidative quality. The fatty acid profile range presented a low n-6/n-3 ratio (1.81–3.38), low atherogenic (2.86–3.11) and thrombogenicity (3.27–3.60) indices and reduced cholesterol content (136–143 mg 100 g⁻¹). In addition, Azorean butters have a high content of conjugated linoleic acid (0.44–0.64 mg 100 g⁻¹), β-carotene (0.12–0.17 mg 100 g⁻¹) and α-tocopherol (1.40–2.20 mg 100 g⁻¹). Sensory analysis revealed high scores for appearance, consistency and flavour of all brands. These results indicate that Azorean butters produced from cows’ milk based on grass-feeding have a potentially healthier fat content and a desirable flavour that, associated with its “natural image”, may be promoted for product differentiation.     

Production of conjugated linoleic acid enriched milk and dairy products from cows receiving grass silage supplemented with a cereal-based concentrate containing rapeseed oil

Opportunities for the production of milk and dairy products enriched with cis-9, trans-11 conjugated linoleic acid (CLA) were investigated. Eighteen mid-lactation cows were used in a continuous-design for 7 weeks. During the first week, cows received grass silage ad libitum supplemented with 10 kg per day of a cereal-based concentrate (control) that was replaced with a concentrate containing 50 g kg⁻¹ of rapeseed oil (RO). Changes in milk fatty acid composition were monitored on a weekly basis and milk produced was used to manufacture Edam cheese and butter. Inclusion of RO in the concentrate supplement increased the mean levels of trans-octadecanoic, monounsaturated, CLA and polyunsaturated fatty acid in the milk fat from 1.6, 25.7, 0.46 and 2.8 to 4.3, 35.3, 1.02 and 3.9 g 100 g⁻¹ total fatty acids, respectively. In contrast, the mean level of saturated fatty acids decreased from 71.4 to 60.7 g  100 g⁻¹ total fatty acids. Changes in milk fatty acid composition due to RO occurred within 7 days, with responses reaching a plateau after 21 days. Furthermore, the CLA concentrations in the milk fat from individual cows ranged between 0.37 and 0.65 and 0.43 and 2.06 g 100 g⁻¹ total fatty acids for the control and RO diet, respectively. CLA enriched milk was used successfully to manufacture of Edam cheese and butter with softer textures but with acceptable organoleptic and storage properties. Processing milk into butter or cheese had no effect on the CLA concentrations indicating that enrichment of dairy products is dependent on the content in raw milk fat.     

Concentrations and Profiles of Polycyclic Aromatic Hydrocarbons in Some Commercial Brands of Tea-, Coffee-, and Cocoa-Based Food Drinks in Nigeria

Concentrations and profiles of polycyclic aromatic hydrocarbons were determined in some popular commercial brands of tea-, coffee-, and cocoa-based food drinks in Nigeria by gas chromatograph-flame ionization after hexane/dichloromethane extraction and clean up. The concentrations of the ∑16 Polycyclic aromatic hydrocarbons in these products ranged from 5.2–913.1, 38.7–593.1, and 38.0–1406.4 μg kg^?1 for tea-, coffee-, and cocoa-based food drinks, respectively. The polycyclic aromatic hydrocarbon profiles indicate the dominance of three and four rings PAHs in these food items. The concentrations of the European Food Safety Authority (EFSA) eight carcinogenic polycyclic aromatic hydrocarbons ranged from nd–218.9, nd–102.9, and nd–1248.5 μg kg^?1 for tea-, coffee-, and cocoa-based food drinks, respectively.     

Polycyclic aromatic hydrocarbons in smoked cheese

BACKGROUND: Polycyclic aromatic hydrocarbons (PAHs) represent a group of organic compounds containing two or more aromatic rings. Their control in the human food chain is required due to the mutagenic and carcinogenic potential, exhibited in vertebrates. In the present study, the occurrence of PAHs in 36 cheeses smoked by various processes was investigated. RESULTS: PAH concentrations (sum of 15 US EPA PAHs) found in samples smoked under controlled industrial conditions were at level 0.11 µg kg^?1, whereas in ‘home‐made’ cheeses, the PAH content was up to 10 times higher. A similar trend was observed for B[a]P, a marker compound representing carcinogenic PAHs. While its levels in commercial products prepared by controlled smoking technologies were close to the limit of quantification (0.03 µg kg^?1); in household samples, the B[a]P content ranged from 0.6 to 0.9 µg kg^?1. Significantly higher amounts of PAHs (up to three to six times) were found in surface layers as compared to internal parts of cheese. CONCLUSION: Although smoked cheese is a popular food, only several papers have focused on PAH levels in these products. This paper evaluates the contribution of different smoking technologies to PAH contamination of several cheeses and thus can help in a risk assessment associated with their consumption. Moreover, the study shows the concentration ratios of selected PAHs, from which the type of smoking technology can be indicated. The results obtained in this study also supported the suggestion of the EU Scientific Committee on Food to use benzo[a]pyrene as an indicator of the occurrence of higher‐molecular mass PAHs. Copyright © 2008 Society of Chemical Industry     

Biochemical changes throughout the ripening of a traditional Spanish goat cheese variety (Babia-Laciana)

The physico-chemical characteristics, proteolysis (classical nitrogen fractions, caseins and their degradation products and free amino acids), and lipolysis (fat acidity and free fatty acids) were studied throughout the ripening of three batches of Babia-Laciana cheese, a Spanish traditional variety made from raw goats’ milk. The main compositional characteristics of this cheese at the end of the ripening are its high content of total solids (TS) (78.0±2.4 g 100 g⁻¹ of cheese) and fat (61.1±1.2 g 100 g⁻¹ of TS), the presence of residual lactose (1.6±0.8 g 100 g⁻¹ of TS) and its low content of sodium chloride (1.1±0.7 g 100 g⁻¹ of TS) and ash (2.8±0.5 g 100 g⁻¹ of TS). Its pH values (4.44±0.72) are extraordinarily low. The evolution and final values of the different nitrogen fractions show that this cheese undergoes a very slight proteolysis, a fact which was corroborated when the caseins and their degradation products were quantified: β-casein did not undergo any modification throughout ripening, while only 21% of the α_s-caseins were degraded. Free amino acids content increased by a factor of about 7 throughout ripening, resulting in a high content of γ-amino butyric acid and a low content of glutamic acid at the end of the process. Fat acidity increased very slightly, approximately 4.5 times, during ripening, reaching final values of 3.5±2.2 mg KOH g⁻¹ of fat. The total free fatty acids content showed a similar evolution to fat acidity. At the end of the ripening process, the main free fatty acid was C_18:1, followed by C₁₆ and C₁₀.     

Presence of polycyclic aromatic hydrocarbons in woody chips used as adjuvant in wines, vinegars and distillates

Samples of 15 commercially available batches of wood chips, used in alcoholic beverage industry, were extracted and analyzed for their content in polycyclic aromatic hydrocarbons (PAHs). Total amounts of PAHs varying between 0.96 and 15.1 ng/g of wood were found, with medium to low MW compounds being mainly present. Carcinogenic benzo[a]pyrene was found in such a value, however, not alarming if maximum mandatory levels in food are considered.PAHs content in chips was unaffected by wood origin, size or toasting level while further investigations dealing with phenomena occurring during the wood seasoning could be necessary.     

Formation and mitigation of heterocyclic aromatic amines in fried pork

Heterocyclic aromatic amines (HAAs) are potent mutagens and carcinogens generated during the heat processing of meat. HAAs, which are abundant in processed meat products, include 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline (4,8-DiMeIQx), and 2-amino-1-methyl-6-phenylimidazo [4,5-b] pyridine (PhIP). The content of these three HAAs in fried pork was determined by LC-MS/MS. The effects of frying time and temperature, sample shape, and addition of antioxidants on the generation of HAAs were investigated. The results show that HAAs were produced during frying, and their levels increased with increasing frying time and temperature. Pork patties had the highest concentration of HAAs compared with pork meatballs and pork strips. The addition of antioxidant of bamboo leaves (AOB), liquorice extract, tea polyphenol, phytic acid and sodium iso-ascorbate to pork before frying had an inhibitory effect on HAA generation, with AOB being the most effective antioxidant. Inhibition levels of nearly 69.73% for MeIQx, 53.59% for 4,8-DiMeIQx and 77.07% for PhIP in fried pork were achieved when the concentrations of AOB added were 0.02, 0.01 and 0.10 g kg^?1, respectively.     

Enrichment of the conjugated linoleic acid content of bovine milk fat by dry fractionation

This study investigated the effect of fat fractionation on the conjugated linoleic acid (cis-9, trans-11-C_18 : 2) content of bovine milk fat. Anhydrous milk fat was fractionated into hard and soft fractions using controlled cooling and agitation. Fractionation of milk fat pre-melted at 60°C using a temperature programme of 33–10°C and a cooling rate of 0.58°C h⁻¹ yielded a soft fraction containing 63.2% more conjugated linoleic acid (2.22 g 100 g⁻¹ FAME), which was also enriched in polyunsaturated fatty acids and vaccenic acid (trans-11-C_18 : 1) compared with the parent fat. Agitation following fractionation was found to have a negative effect on the conjugated linoleic acid content of the soft fraction. Refractionation of the soft fraction did not increase the yield of conjugated linoleic acid. The conjugated linoleic acid and trans fatty acid content of 26 selected food products ranging in milk fat content from 0 to 100% is reported. Conjugated linoleic acid concentrations ranged from 0 to 16.2 mg g⁻¹ fat and were generally lower than the trans fatty acid content which ranged from 0 to 155.7 mg g⁻¹ fat. Spreads containing vegetable oils contained higher trans fatty acid and lower conjugated linoleic acid contents than milk fat-containing products. This study highlights that a milk fat fraction enriched in conjugated linoleic acid may be achieved by dry fractionation.