1630 Journal of Food Protection, Vol. 77, No. 9, 2014, Pages 1630-1633 doi: 10.4315/0362-028X.JFP-14-054 C o pyright © , Internatio nal A sso cia tio n fo r Food Protection
Research Note
Polycyclic Aromatic Hydrocarbon Generation in Heat-Processed Sundried Salt JIN HYO KIM,1* SO-YOUNG KIM , 2 GEUN-HYOUNG CHOI, 1 a n d JI-HAE LEE 1 'Chemical Safety Division and functional Food Division, National Academy of Agricultural Sciences, RDA, Suwon, Gyeonggi, 441-707, Republic of Korea MS 14-054: Received 28 January 2014/Accepted 22 April 2014
ABSTRACT An investigation of polycyclic aromatic hydrocarbon (PAH) generation in sundried salt samples was conducted. Of the 16 priority PAHs tested for, naphthalene was revealed as the most dominant PAH, with residual concentrations measured as 0.33 to 7.02 ng/g after sundried salt heat processing over temperatures ranging from 250 to 700°C. Eleven organic carbon sources were tested to determine the relationship between carbon source and PAH generation under various heat-processing conditions. Citric acid was found to be the most significant contributor to PAH generation in salt. Investigations of PAH contamination levels were conducted for 32 commercial sundried salts and 73 heat-processed salts; none of the PAHs tested for were detected in any of the commercial salts examined.
Polycyclic aromatic hydrocarbons (PAHs) are known for their carcinogenic and mutagenic properties (2 , 20 ). The U.S. Environmental Protection Agency has classified 16 PAHs as priority toxic chemicals; these compounds include acenaphthene, acenaphthylene, anthracene, benzo [61fluor anthene, benz[a]anthracene, benzol^[fluoranthene, benzo [ «,/?,/]perylene, benzol a Jpyrene, chrysene, dibenz[a,/f|an thracene, fluoranthene, fluorene, indenof 1,2,3-c,r/]pyrene, naphthalene, phenanthrene, and pyrene. Among the chemicals listed, benzo[a]pyrene is the most examined carcinogen of environmental concern, and its distributions and safety guidelines have been studied and reported for both the environment (15, 20 , 21) and heat-treated foods (3 , 17, 19). PAHs are generated during incomplete combustion processes and pyrolysis reactions (25). Some studies have demonstrated the pyrolysis of organic carbon materials at temperatures over 600°C to be a major high-yielding environmental contributor of PAHs (13); a suggested mechanism of PAH formation involves the addition of acetylene and/or butadiene to aromatic rings (24 , 25). Furthermore, McGrath et al. ( 13) and other researchers have investigated the influence of carbon sources on the yield and variety of PAHs generated by pyrolysis (1, 18, 22). Although these pyrolysis-generated PAHs have been extensively studied for several decades, few reports exist that discuss the generation and distribution of PAHs by incomplete combustion, in spite of the high possibility of contamination during baking, frying, and roasting of food. Recently, the South Korean food industry has become interested in the use of heat-processed salt for food * Author for correspondence. Tel: +82-31-290-0523; Fax: + 82-31-2900506; E-mail: [email protected].
preparation because of its remarkable functional properties, including antioxidant (30), anticancer (29 , 31), antihyper tension (10), anti-inflammatory (23), antimicrobial (14), and immunomodulator (9) benefits, as well as its ability to improve the qualities of fermented food (4 ), meat (6 ), and wet noodles (11). In particular, bamboo salt has become the most recognized of commercialized melted salts due to numerous studies on its health benefits and toxicity (7) and because it possesses a long history as part of South Korean traditional medicine. This interest has prompted recent growth in the market for heat-processed salts with herbs. However, the heat-related contamination of salts has not been fully studied from the viewpoint of food safety, with the exception of dioxin contamination in melted salts (28); the determination of PAH content in heat-treated salts, as a potential carcinogen generated through heat processes, is therefore of great importance. Here, we report the results of our investigations of residual PAHs in salts and identify the major carbon contributors to PAH generation in roasted salt. MATERIALS AND METHODS PAH standards and chemicals. All the purchased chemicals had purities greater than reagent grade. The reagents used were sodium chloride (Merck, Darmstadt, Germany), galactose (SigmaAldrich, St. Louis, MO), starch (Sigma-Aldrich), peptone (BD, Franklin Lakes, NJ), yeast extract (BioShop, Burlington, Canada), histidine (TCI, Tokyo, Japan), tryptophan (Sigma-Aldrich), phenyl alanine (Sigma-Aldrich), tannic acid (Sigma-Aldrich), ascorbic acid (Sigma-Aldrich), gallic acid (Sigma-Aldrich), caffeic acid (SigmaAldrich), and citric acid (Sigma-Aldrich). Standard solutions (100 pg/ ml) of the 16 PAHs (acenaphthene, acenaphthylene, anthracene, benzol b [fluoranthene, benz[a]anthracene, benzo [T]fluoranthene, benzo[g,/v']perylene, benzo[a]pyrene, chrysene, dibenz[a,/t (anthra cene, fluoranthene, fluorene, indenof 1,2,3-c:,
Research Note
Polycyclic Aromatic Hydrocarbon Generation in Heat-Processed Sundried Salt JIN HYO KIM,1* SO-YOUNG KIM , 2 GEUN-HYOUNG CHOI, 1 a n d JI-HAE LEE 1 'Chemical Safety Division and functional Food Division, National Academy of Agricultural Sciences, RDA, Suwon, Gyeonggi, 441-707, Republic of Korea MS 14-054: Received 28 January 2014/Accepted 22 April 2014
ABSTRACT An investigation of polycyclic aromatic hydrocarbon (PAH) generation in sundried salt samples was conducted. Of the 16 priority PAHs tested for, naphthalene was revealed as the most dominant PAH, with residual concentrations measured as 0.33 to 7.02 ng/g after sundried salt heat processing over temperatures ranging from 250 to 700°C. Eleven organic carbon sources were tested to determine the relationship between carbon source and PAH generation under various heat-processing conditions. Citric acid was found to be the most significant contributor to PAH generation in salt. Investigations of PAH contamination levels were conducted for 32 commercial sundried salts and 73 heat-processed salts; none of the PAHs tested for were detected in any of the commercial salts examined.
Polycyclic aromatic hydrocarbons (PAHs) are known for their carcinogenic and mutagenic properties (2 , 20 ). The U.S. Environmental Protection Agency has classified 16 PAHs as priority toxic chemicals; these compounds include acenaphthene, acenaphthylene, anthracene, benzo [61fluor anthene, benz[a]anthracene, benzol^[fluoranthene, benzo [ «,/?,/]perylene, benzol a Jpyrene, chrysene, dibenz[a,/f|an thracene, fluoranthene, fluorene, indenof 1,2,3-c,r/]pyrene, naphthalene, phenanthrene, and pyrene. Among the chemicals listed, benzo[a]pyrene is the most examined carcinogen of environmental concern, and its distributions and safety guidelines have been studied and reported for both the environment (15, 20 , 21) and heat-treated foods (3 , 17, 19). PAHs are generated during incomplete combustion processes and pyrolysis reactions (25). Some studies have demonstrated the pyrolysis of organic carbon materials at temperatures over 600°C to be a major high-yielding environmental contributor of PAHs (13); a suggested mechanism of PAH formation involves the addition of acetylene and/or butadiene to aromatic rings (24 , 25). Furthermore, McGrath et al. ( 13) and other researchers have investigated the influence of carbon sources on the yield and variety of PAHs generated by pyrolysis (1, 18, 22). Although these pyrolysis-generated PAHs have been extensively studied for several decades, few reports exist that discuss the generation and distribution of PAHs by incomplete combustion, in spite of the high possibility of contamination during baking, frying, and roasting of food. Recently, the South Korean food industry has become interested in the use of heat-processed salt for food * Author for correspondence. Tel: +82-31-290-0523; Fax: + 82-31-2900506; E-mail: [email protected].
preparation because of its remarkable functional properties, including antioxidant (30), anticancer (29 , 31), antihyper tension (10), anti-inflammatory (23), antimicrobial (14), and immunomodulator (9) benefits, as well as its ability to improve the qualities of fermented food (4 ), meat (6 ), and wet noodles (11). In particular, bamboo salt has become the most recognized of commercialized melted salts due to numerous studies on its health benefits and toxicity (7) and because it possesses a long history as part of South Korean traditional medicine. This interest has prompted recent growth in the market for heat-processed salts with herbs. However, the heat-related contamination of salts has not been fully studied from the viewpoint of food safety, with the exception of dioxin contamination in melted salts (28); the determination of PAH content in heat-treated salts, as a potential carcinogen generated through heat processes, is therefore of great importance. Here, we report the results of our investigations of residual PAHs in salts and identify the major carbon contributors to PAH generation in roasted salt. MATERIALS AND METHODS PAH standards and chemicals. All the purchased chemicals had purities greater than reagent grade. The reagents used were sodium chloride (Merck, Darmstadt, Germany), galactose (SigmaAldrich, St. Louis, MO), starch (Sigma-Aldrich), peptone (BD, Franklin Lakes, NJ), yeast extract (BioShop, Burlington, Canada), histidine (TCI, Tokyo, Japan), tryptophan (Sigma-Aldrich), phenyl alanine (Sigma-Aldrich), tannic acid (Sigma-Aldrich), ascorbic acid (Sigma-Aldrich), gallic acid (Sigma-Aldrich), caffeic acid (SigmaAldrich), and citric acid (Sigma-Aldrich). Standard solutions (100 pg/ ml) of the 16 PAHs (acenaphthene, acenaphthylene, anthracene, benzol b [fluoranthene, benz[a]anthracene, benzo [T]fluoranthene, benzo[g,/v']perylene, benzo[a]pyrene, chrysene, dibenz[a,/t (anthra cene, fluoranthene, fluorene, indenof 1,2,3-c:,
