Formation Of Polycyclic Aromatic Hydrocarbons Research Articles

Effects of fuel composition and octane sensitivity on polycyclic aromatic hydrocarbon and soot emissions of gasoline–ethanol blend surrogates

The sooting propensity of a fuel is closely coupled with the fuel composition and chemistry. A detailed understanding of their effects is, therefore, needed to develop next-generation fuels which can minimize particulate emissions. With this overarching goal, the present work numerically investigates the effects of fuel composition and octane sensitivity (S) on polycyclic aromatic hydrocarbons (PAH) and soot emissions, for four-component gasoline–ethanol blend surrogates comprising isooctane, n-heptane, toluene, and ethanol. A partially-premixed counterflow flame is chosen as the canonical configuration for this study and simulations are performed using CHEMKIN-Pro-employing a kinetic mechanism developed by Park et al. (2017). In addition, a, detailed soot model based on the sectional method is used to capture the spatial characteristics of soot emissions. The kinetic mechanism and soot model are validated using available experimental data for various targets. A total of 86 TPRF-E mixtures, spanning a wide range of concentration of each component, and a wide range of S are analyzed. The effect of each non-paraffinic fuel component on the resultant PAH and soot emissions is investigated. PAH and soot emissions are found to vary significantly depending upon the blend composition. Based on the parametric sweeps, a regression analysis is carried out to identify global parameters that govern the formation of PAHs and soot. The analysis shows that both toluene content and S have a prominent effect on the formation of PAHs and soot, with toluene content having a stronger impact. Moreover, larger PAHs have higher dependency on toluene content and S. Furthermore, a detailed analysis is carried out to understand the physical and chemical phenomena associated with the observed trends of PAH and soot emissions.

Flow reactor pyrolysis of iso-butylbenzene and tert-butylbenzene at various pressures: Insight into fuel isomeric effects on pyrolysis chemistry of butylbenzenes

This work reports an experimental and kinetic modeling investigation on the flow reactor pyrolysis of iso-butylbenzene and tert-butylbenzene at 0.04 and 1 atm. Pyrolysis products were detected and identified using synchrotron vacuum ultraviolet photoionization mass spectrometry, and their mole fractions versus heating temperature were measured. High-pressure-limit and pressure-dependent rate constants of unimolecular decomposition reactions of iso-butylbenzene were calculated in this work using the same method as the theoretical calculation investigation on similar reactions of n-butylbenzene, sec-butylbenzene and tert-butylbenzene reported by Belisario-Lara et al. [J. Phys. Chem. A, 122 (2018) 3980–4001]. Furthermore, a pyrolysis model of four butylbenzene isomers was developed from our previous models of n-butylbenzene and sec-butylbenzene and validated by the present experimental data. Modeling analysis was performed to reveal key pathways in fuel decomposition and polycyclic aromatic hydrocarbon (PAH) formation of iso-butylbenzene and tert-butylbenzene. The dominant decomposition reactions of iso-butylbenzene and tert-butylbenzene under pyrolysis conditions are benzylic CC bond dissociation reactions, while the major products in pyrolysis process are produced by β-scission reactions of primary radical products. Fuel-specific pathways are found to strongly affect the formation of PAHs, especially for indene, naphthalene and phenanthrene. Fuel isomeric effects on the pyrolysis of four butylbenzene isomers were also analyzed with special concerns on the fuel decomposition and PAH formation processes. Different sidechain structures result in different distributions of major products, while different formation pathways and concentrations of precursors lead to different formation tendency of typical PAHs.

Determination of absolute photoionization cross-sections of some aromatic hydrocarbons.

Aromatic hydrocarbons play an important role in the formation and growth of polycyclic aromatic hydrocarbon (PAH) and soot particles. Measurements of their absolute photoionization cross-sections (PICSs), that benefit the quantitative investigation of mass spectrometry, are still lacking, however. PICSs of some aromatic hydrocarbons were measured with tunable synchrotron vacuum ultraviolet photoionization mass spectrometry (SVUV-PIMS). Nitric oxide and benzene were chosen as standard references for PICS calibration, since their photoionization cross-sections are well documented in the literature. Binary liquid mixtures of the investigated molecules and their specific solvents were used in the measurements. The investigated aromatics include naphthalene, phenanthrene, 1-methylnaphthalene, indene, 2-/3-/4-methylphenylacetylene, 2-methylindene, diphenylacetylene, 1-/2-ethynylnaphthalene and acenaphthylene. Photo-induced fragments from the molecules were also observed with increasing photon energy. Based on our measurements and literature data, PICSs of most aromatic molecules have very similar values beyond their ionization energies. However, molecules that contain the phenylacetylene structure have PICSs higher than other aromatics.

Effects of Honey-Spices Marination on Polycyclic Aromatic Hydrocarbons and Heterocyclic Amines Formation in Gas-Grilled Beef Satay

The effects of honey-spices marination on simultaneous formation of polycyclic aromatic hydrocarbons (PAHs) and heterocyclic amines (HCAs) in gas-grilled beef satay were investigated at different grilling temperatures (150 °C, 250 °C, and 350 °C). Beef satay samples used in this study were prepared using two types of honey-spices marination (Apis mellifera-spices and Trigona sp.-spices). Quantifications of fifteen PAHs using high performance liquid chromatography with fluorescence detection (HPLC-FLD) and nine HCAs using liquid chromatography tandem-mass spectrometry (LC–MS/MS) were performed with gradient programme. Results on PAHs and HCAs in marinated samples were compared with control. Highest concentrations (p < 0.05) of PAHs (marinated beef satay) and HCAs (control) were detected at 350 °C. The most prominent PAH and HCA were phenanthrene (24.61–84.36 ng/g) and 9H-pyrido-[4,3-b]indole (Norharman) (2.67–393.89 ng/g). Marination significantly (p < 0.05) reduced naphthalene, fluorene, pyrene, 2-amino-9H-pyrido[2,3-b]indole (AαC), 1-methyl-9H-pyrido-[4,3-b]indole (Harman), and Norharman in gas-grilled beef satay across all temperatures. Overall, inverse quantitative profiles of PAHs and HCAs formation were observed in marinated gas-grilled beef satay.

Influence of temperature on products from fluidized bed pyrolysis of wood and solid recovered fuel

The fluidized bed fast pyrolysis of two different kinds of fuels, namely, wood pellets (WP) and solid recovered fuel (SRF) pellets made up of a municipal solid waste by ECONWARD TECH, S.L. (EP) has been carried out. Thus, the analysis of the influence of pyrolysis reactor temperature (600–800 °C) and fuel type in terms of product distribution, e.g. gases, char and tar has been performed. The conditions used in this work are of special interest for the gasification in fluidized beds, in which fast pyrolysis plays a relevant role as it is the first step of fuel conversion. The gas composition was continuously recorded and the tar samples collected during the experiments were analyzed by GC technique. The higher ash content in the EP enhanced charring and decarboxylation reactions, which greatly influenced the distribution of the gaseous products leading to a high CO2 yield. Tar composition was also affected by the constituents of the fuels used, with the content of phenolic compounds in the EP tar obtained at 650 °C being particularly low at the expense of a higher light aromatic content. The rise in temperature decreased the fraction of phenolic compounds and led to a gradual formation of light and heavy polycyclic aromatic hydrocarbons (PAHs), with naphthalene being the major compound in tars of both fuels, WP and EP, at high temperature. The results can be used to derive pyrolysis sub-models for fluidized bed gasification modeling.

Low- and high-temperature study of n-heptane combustion chemistry

n-Heptane has been used extensively in various fundamental combustion experiments as a prototypical hydrocarbon fuel. While the formation of polycyclic aromatic hydrocarbon (PAH) in n-heptane combustion has been studied preferably in premixed flames, this study aims to investigate the combustion chemistry of n-heptane in less-studied diffusion flame and highly rich high-temperature homogeneous oxidation configurations by using a counterflow burner and a flow reactor, respectively. This work addresses the formation of higher-molecular species in the mass range up to about 160 u in both configurations. Samples are analyzed by time-of-flight (TOF) molecular beam mass spectrometry (MBMS) using electron-impact (EI) and single-photon ionization (PI). Highly resolved speciation data are reported. Laminar flow reactor experiments cover a wide temperature range. Especially the measurements at low temperatures provide speciation data of large oxygenates produced in the low-temperature oxidation of n-heptane, which are scarce in the literature. Important precursor molecules for PAH and soot formation, such as C9H8, C10H8, C11H10, and C12H8, are formed during the high-temperature combustion process in the counterflow flame, while oxygenated growth species are observed under low-temperature conditions, even at the fuel-rich equivalence ratio of ϕ=4.00.Numerical modeling for both conditions is performed by using a newly developed kinetic model of n-heptane, which includes the n-heptane and PAH formation chemistry with state-of-the-art kinetic knowledge. Good agreement between model predictions and experimental data of counterflow flame and flow reactor is observed for the major species and some intermediates of n-heptane oxidation. While the concentrations of benzene and toluene measured in the counterflow burner are well-reproduced, the numerical results for flow reactor data are not satisfactory. Differences are found between the formation pathways of fulvene, from whose isomerization benzene is produced in diffusion flame and flow reactor.

Water vapour effects on temperature and soot loading in ethylene flames in hot and vitiated coflows

Flames in hot, low oxygen environments exist in a variety of practical applications. These conditions result in significant mixing between fuel and combustion products, such as water vapour, or diluents included for emissions control. The chemical and physical effects of water vapour as a diluent are investigated in a series of ethylene flames in a jet in hot coflow burner to determine the effects on temperature and soot fields. The combined analyses of photographs, non-linear excitation regime two-line atomic fluorescence (NTLAF) of indium, planar laser-induced incandescence (LII) and one-dimensional opposed-flow flame simulations demonstrate the dominance of the chemistry, driven by the hot and vitiated oxidant, in soot reduction. Although photographs appear to suggest that both highly vitiated coflows, and highly diluted jet flames have global effect on the flames, detailed measurements reveal significantly different trends in their soot and temperature fields. The chemical contribution of water vapour as a reactant, as a third-body in ethylene decomposition and a source of H and OH in the rich mixture is further described, and trends subsequently identified, in the context of formation of polycyclic aromatic hydrocarbons and soot reduction.

Influence of Different Smoking Procedures on Polycyclic Aromatic Hydrocarbons Formation in Traditional Dry Sausage Hercegovačka kobasica

The concentrations of 16 polycyclic aromatic hydrocarbons (PAH) in smoked dry sausage Hercegovačka kobasica were investigated. The sausages were stuffed in two different casings (collagen and natural) and smoked in traditional and industrial smokehouses. The highest concentration of PAH 16 were detected in sausages in natural casings smoked in the traditional manner. The samples smoked in the industrial chamber stuffed in collagen casing showed the lowest PAH 16 content. The content of PAH 4 in sausage smoked in the traditional way and stuffed in natural casing averaged 24.46 µg/kg, which is more the double of maximum prescribed concentration of 12 µg/kg. The concentration of cancerogenic benzo[a]pyrene averaged 7.79 µg/kg in sausage stuffed in natural casing and smoked in the traditional way, which is almost four times the legislative prescribed values (2 µg/kg). Sausage smoked in the traditional manner and stuffed in collagen casing showed lower values for PAH 4 (13.88 µg/kg) and benzo[a]pyrene (4.97 µg/kg), but these values were also above the legislative prescribed values.

Changes in light absorption by brown carbon in soot particles due to heterogeneous ozone aging in a smog chamber

Light absorption by brown carbon (BrC) is dynamic due to atmospheric aging processes, leading to complex and poorly constrained effects on photochemistry and climate. In this study, a smog chamber was used to simulate the heterogeneous ozone (O3) aging of soot particles. Twelve aging times and seven O3 concentrations were set to investigate the effects of aging degree on BrC light absorption. The results showed that light absorption by BrC was enhanced after O3 aging, but followed a non-monotonic trend with an initial increase and subsequent decrease. An aging time of 60 min and O3 concentration of 1.2 ppm were optimal for enhancing BrC absorption, where the contribution of BrC to total absorption and the contribution of BrC relative to black carbon absorption at 370 nm of ozonized soot were 23.0 ± 1.8% and 30.0 ± 3.0%, respectively, much greater than those of fresh soot (8.1 ± 1.1% and 8.8 ± 1.3%, respectively). The absorption Ångström exponent (AAE) and delta C (ΔC) of ozonized soot at 60 min ranged from 1.18 ± 0.01 to 1.31 ± 0.03 and from 13.5 ± 7.0 to 24.3 ± 13.5 μg m−3, respectively, and were greater than those of fresh soot (1.12 ± 0.02 and 8.0 ± 0.8 μg m−3), but also showed non-monotonic trends, suggesting the formation of BrC during O3 aging. Comparative results indicated that AAE might be a better BrC indicator for soot than ΔC. The non-monotonic trend was tentatively explained by changes in organic carbon, oxygenated functional groups and conjugated structures, as well as polycyclic aromatic hydrocarbon (PAH) degradation and oxygenated PAH formation. The relative intensities of oxidative formation and degradation of chromophores may determine BrC evolution during O3 aging. This study will be useful for clarifying BrC evolution in the atmosphere and estimating its radiative forcing.

Probing PAH formation chemical kinetics from benzene and toluene pyrolysis in a single-pulse shock tube

Benzene and toluene were pyrolyzed under highly argon-diluted conditions at a nominal pressure of 20 bar in a single-pulse shock tube coupled to gas chromatography/gas chromatography–mass spectrometry (GC/GC–MS) diagnostics. Concentration evolutions of polycyclic aromatic hydrocarbon (PAH) intermediates were measured in a temperature range of 1100–1800 K by analyzing the post-shock gas mixtures. Different PAH speciation behaviors, regarding types, concentrations and formation temperature windows, were observed in the two reaction systems. A kinetic model was proposed to predict and interpret the measurements. Through a combination of experimental and modeling efforts, PAH formation patterns from species pools of benzene and toluene pyrolysis were illustrated. In both cases, channels leading to PAHs basically originate from the respective fuel radicals, phenyl and benzyl. Due to the higher thermal stability of benzene, the production of phenyl, and thus most PAH species, occur in higher temperature windows, in comparison to the case of toluene. In benzene pyrolysis, benzyne participates in the formation of crucial PAH species such as naphthalene and acenaphthylene. Phenyl self-recombination takes considerable carbon flux into biphenyl, which serves as an important intermediate leading to acenaphthylene through hydrogen loss and ring closure. The resonantly-stabilized benzyl is abundant in toluene pyrolysis, and its decomposition further produces other resonantly-stabilized radicals such as fulvenallenyl and propargyl. Barrierless addition reactions among these radicals are found to be important sources of PAHs. Fuel-specific pathways have pronounced effects on PAH speciation behaviors, particularly at lower temperatures where fuel depletion is not completed within the reaction time of 4.0 ms. Contributions from the commonly existing Hydrogen-Abstraction-Carbon-Addition (HACA) routes increase with the temperature in both cases.

Catalytic fast pyrolysis of enzymatic hydrolysis lignin over Lewis-acid catalyst niobium pentoxide and mechanism study

Lewis-acid catalyst Nb2O5 is first applied in catalytic fast pyrolysis (CFP) of enzymatic hydrolysis lignin (EHL) to produce aromatic hydrocarbons (AHs) that can be used as alternative liquid fuels. The catalyst exhibits a good talent to convert lignin into AHs with quite little polycyclic aromatic hydrocarbons (PAHs) formation. The yield of AHs reaches 11.2 wt% and monocyclic aromatic hydrocarbons (MAHs) takes up 94% under the optimized condition (Catalyst to Lignin ratio 9:1, 650 °C). No coke is generated during the reactions. The reaction sequence is proposed and verified by model compound reactions. Furthermore, DFT calculations are performed to understand the mechanisms of limitation of PAHs or char/coke formation and the efficient deoxygenation ability over catalyst. Nb2O5 with Lewis acid sites is proved to be a promising catalyst for the production of AHs from lignin. This work provides a new idea on choice of catalysts for CFP of lignin in future.

Analysis, formation and inhibition of polycyclic aromatic hydrocarbons in foods: An overview

Polycyclic aromatic hydrocarbons (PAHs), formed through incomplete combustion or pyrolysis of wood or gasoline, represents an important class of toxicological compounds because of its wide distribution in the environment and possible contamination of foods. This paper deals with an overview of analysis, formation and inhibition of PAHs in foods. Extraction of PAHs from food is routinely conducted by saponification of lipid with Soxhlet method, followed by purification with a Sep-Pak Florisil cartridge and partition. This method can remove more impurities than the sonication method. With HPLC, all 16 PAHs can be simultaneously separated by a gradient solvent system and detected by UV at 254 nm or fluorescence employing programmable wavelength with seven settings of excitation/emission. With GC, all 16 PAHs can also be simultaneously separated by a temperature programming method and detected by flame ionization detector (FID) or ion-trap mass detector (ITD). Although HPLC can provide adequate separation of 16 PAHs, nevertheless, the presence of impurities in food sample can interfere with the subsequent identification and separation. For GC, a number of isomeric PAHs partially overlap. Nonetheless, the application of GC-ITD can readily identify the various PAHs in foods through reconstructed ion chromatograms even in the presence of fat- or PAH-like impurities. Charcoal-grilling and smoking are the two major processing methods which can result in the formation of high amount of total carcinogenic PAHs. No carcinogenic PAHs are detected in steaming and liquid smoke flavoring. The amount of PAHs in food samples can also be greatly reduced by sorption into low-density polyethylene bags. Further research in necessary to determine how the formation of PAHs during processing can be directly retarded or eliminated.

Cover Image, Volume 44, Issue 7

The cover image is based on the Original Article Application of grape seed extract lead to a higher formation of polycyclic aromatic hydrocarbons in roasted pork sausage at the end of storage by Cai Kezhou, Yuzhu li, Wei Xing et al., https://doi.org/10.1111/jfpp.14532.

Dual-Scale Flamelet/Progress Variable Approach for Prediction of Polycyclic Aromatic Hydrocarbons Formation under the Condition of Coal Combustion

A dual-scale flamelet/progress variable (DS-FPV) approach is developed to predict polycyclic aromatic hydrocarbon (PAH) formation in the environment of coal combustion. An additional progress varia...

Chemical Effects of CO2 and H2O Addition on Aromatic Species in Ethanol/Air Diffusion Flame

ABSTRACT Exhaust gas recirculation (EGR) is an effective technique used widely to meet current emission regulations. In this work, the mechanism of H2O and CO2 addition (a main component of exhaust gas) on polycyclic aromatic hydrocarbons (PAHs, the precursor of soot) formation was investigated numerically in ethanol diffusion flames, motivated by current concerns on particulate matter (PM) emissions when ethanol is applied to modern gasoline engines, especially under high load and temperature. To understanding the underlying mechanisms of H2O and CO2 on ethanol flame, a comprehensive chemical kinetic analysis was performed by modeling gas-phase chemistry with PAHs formation up to pyrene. In order to distinguish the important chemical role of H2O and CO2 addition through partial replacement of N2 from their thermal effects, additional calculations were performed with two fictitious species. The numerical results show that the thermal effect of H2O and CO2 reduces the peak flame temperature, but their chemical effect influences the peak flame temperature differently. The results also showed that the addition of either H2O or CO2 led to a significant reduction of PAHs via thermal and chemical effects. The chemical suppressing effect of H2O and CO2 addition on PAHs formation was identified and attributed to reduced PAHs precursor species and slow of PAH growth process. However, reaction pathway analysis showed that the chemical effects of H2O and CO2 influence the PAHs chemistry differently.

The Chemistry of Cosmic Dust Analogues from C, C2, and C2H2 in C-Rich Circumstellar Envelopes.

Interstellar carbonaceous dust is mainly formed in the innermost regions of circumstellar envelopes around carbon-rich asymptotic giant branch (AGB) stars. In these highly chemically stratified regions, atomic and diatomic carbon, along with acetylene are the most abundant species after H2 and CO. In a previous study, we addressed the chemistry of carbon (C and C2) with H2 showing that acetylene and aliphatic species form efficiently in the dust formation region of carbon-rich AGBs whereas aromatics do not. Still, acetylene is known to be a key ingredient in the formation of linear polyacetylenic chains, benzene and polycyclic aromatic hydrocarbons (PAHs), as shown by previous experiments. However, these experiments have not considered the chemistry of carbon (C and C2) with C2H2. In this work, by employing a sufficient amount of acetylene, we investigate its gas-phase interaction with atomic and diatomic carbon. We show that the chemistry involved produces linear polyacetylenic chains, benzene and other PAHs, which are observed with high abundances in the early evolutionary phase of planetary nebulae. More importantly, we have found a non-negligible amount of pure and hydrogenated carbon clusters as well as aromatics with aliphatic substitutions, both being a direct consequence of the addition of atomic carbon. The incorporation of alkyl substituents into aromatics can be rationalized by a mechanism involving hydrogen abstraction followed by methyl addition. All the species detected in gas phase are incorporated into the nanometric sized dust analogues, which consist of a complex mixture of sp, sp2 and sp3 hydrocarbons with amorphous morphology.

Formation of Polycyclic Aromatic Hydrocarbons (PAHs) and Oxygenated PAHs in the Oxidation of Ethylene Using a Flow Reactor

ABSTRACT Interest in polycyclic aromatic hydrocarbons (PAHs) including a functional group in its chemical structure, particularly oxygenated PAHs (OPAHs), has been growing due to the toxicity and wide presence of the compound. Understanding the formation mechanism of OPAHs is very important for reducing their emission during combustion. However, studies on the quantitative evaluation of OPAHs have been very limited. In this study, the formation of OPAHs was quantitatively evaluated in addition to that of PAHs using a flow reactor system in which a mixture of ethylene, O2, and N2 reacted at atmospheric pressure. 5 types of OPAHs were targeted in this study: phenol, benzofuran, dibenzofuran, 9-fluorenone, and benzanthrone. 3 types of monocyclic aromatic hydrocarbons (MAHs) and 17 types of PAHs were also analyzed by gas chromatography mass spectrometry. Measurements were performed at different reaction gas temperatures (1050 to 1350 K), residence times (0.40 to 1.5 second), and equivalence ratios (3.0 to 12.0). Some measured data, mainly MAHs and PAHs, were compared with the concentrations predicted using existing kinetic models. Finally, we evaluated the reaction pathways that contributed to the formation of the OPAHs such as benzofuran, dibenzofuran, 9-fluorenone, and benzanthrone quantified in this study.

The incorporation of polysaccharides in grilled beef patties: influence on the levels of polycyclic aromatic hydrocarbons and heterocyclic aromatic amines

The effects of wheat fiber (1 and 2%) and the mixture of xanthan and guar gums (0.5%; 4:1) incorporations in beef patties on the levels of formed polycyclic aromatic hydrocarbons (PAHs) and heterocyclic aromatic amines (HCAs) were evaluated. In this regard, the samples were stored at − 18 °C during different storage times (days 0, 45, and 90) and then were grilled at 175 °C for 5 min. At day 0, a significant (P < 0.05) difference in the formation of PAHs and HCAs among treated beef patties and control samples was noted. The formation of carcinogenic compounds at day 0 was reduced while fiber and gums together were added. The highest reduction in PAHs and HCAs levels among treatments was related to benzo [b] fluorantene (36–42%) and 2-amino-3-methyl-imidazo [4, 5-f] quinoline (60–74%), respectively. Also, the frozen storage of samples for 45 and 90 days significantly (P < 0.05) caused an increase and decrease in the PAHs and in HCAs levels, respectively. Therefore, the incorporation the combination of wheat fiber (2%), xanthan and guar gums (0.5%) can be suggested as a promising strategy to reduce the levels of PAHs and HCAs in beef patties.

Insights on the role of primary and secondary tar reactions in soot inception during fast pyrolysis of coal

In the present work fast pyrolysis of coal in N2 and CO2 atmospheres was studied in a drop tube reactor (DTR) and in a heated strip reactor (HSR). In the DTR the volatiles generated by coal pyrolysis were entrained in a hot gas stream and were collected at the reactor outlet by tar traps. In the HSR, the volatiles were ejected from the hot coal particles into a cool environment and the condensable species, including primary tar, deposited and/or condensed on a glass bridge located above the heated strip. The composition of tars produced in the two reactors was compared to study the role of gas tar reactions in soot inception, and reference compounds for each class of tar species produced were identified.In the DTR the formation and growth of polycyclic aromatic hydrocarbons (PAH) were found higher than in the HSR. Soot formation occurred only in the DTR, being negligible in the HSR.It was concluded that the hot gas environment of the DTR favours secondary tar reactions, formation of PAH and eventually soot, while in the HSR this path was prevented due to prompt cooling down of volatiles. The presence of large concentration of CO2 in the pyrolysis atmospheres further promoted formation of heavy PAH and soot in the DTR, but not in the HSR, where the cooler environment limits soot-CO2 reactions in the gas phase.

Application of grape seed extract lead to a higher formation of polycyclic aromatic hydrocarbons in roasted pork sausage at the end of storage

Application of grape seed extract lead to a higher formation of polycyclic aromatic hydrocarbons in roasted pork sausage at the end of storage