Effect of cooking on radiation-induced chemical markers in beef and pork during storage.
Raw and cooked beef and pork loins were irradiated at 0 or 5 kGy. The radiation-induced marker compounds, such as hydrocarbons, 2-alkylcyclobutanones (2-ACBs), and sulfur volatiles, were determined after 0 and 6 mo of frozen storage. Two hydrocarbons (8-heptadecene [C(17:1)] and 6,9-heptadecadiene [C(17:2)]) and two 2-ACBs (2-dodecylcyclobutanone [2-DCB] and 2-tetradecylcyclobutanone [2-TCB]) were detected only in irradiated raw and cooked meats. Although precooked irradiated meats produced more hydrocarbons and 2-ACBs than the irradiated cooked ones, the amounts of individual hydrocarbons and 2-ACBs, such as 8-heptadecene, 6,9-heptadecadiene, 2-DCB, and 2-TCB, were sufficient enough to detect whether the meat was irradiated or not. Dimethyl disulfide and dimethyl trisulfide were also determined only in irradiated meats but dimethyl trisulfide disappeared after 6 mo of frozen storage under oxygen-permeable packaging conditions. The results indicated that 8-heptadecene, 6,9-heptadecadiene, 2-DCB, 2-TCB, and dimethyl disulfide, even though they were decreased with storage, could be used as marker compounds for the detection of irradiated beef and pork regardless of cooking under the frozen conditions for 6 mo.


CONCLUSIONS
Radiation-induced chemical changes such as specific hydrocarbons, 2-ACBs, and sulfur volatiles may be used as potential identification markers by regulatory authorities to confirm irradiation history of frozen stored raw or cooked beef and pork.
Dept of Food Science & Technology, Kyungpook Natl Univ, Daegu 702-701, Korea. jhkwon@knu.ac.kr
Joong-Ho
JH
Kwon
Youngju
Y
Kwon
Tusneem
T
Kausar
Ki-Chang
KC
Nam
Byong
B
Rok Min
Eun
E
Joo Lee
Dong U
DU
Ahn
D000475:Alkenes / Q000032:analysis; D000818:Animals; D002417:Cattle; D003296:Cooking; D003503:Cyclobutanes / Q000032:analysis; D004220:Disulfides / Q000032:analysis; D005514:Food Irradiation / Q000379:methods*; D061353:Food Storage; D005615:Freezing; D006838:Hydrocarbons / Q000032:analysis; D008460:Meat / Q000528:radiation effects*; D009812:Odorants; D013552:Swine; D013649:Taste; D055549:Volatile Organic Compounds / Q000032:analysis
C473093:8-heptadecene; D000475:Alkenes; D003503:Cyclobutanes; D004220:Disulfides; D006838:Hydrocarbons; D055549:Volatile Organic Compounds; C021181:dimethyl disulfide; C485436:2-tetradecylcyclobutanone; C063381:2-dodecylcyclobutanone