Sterilization of Scrambled Eggs in Military Polymeric Trays by Radio Frequency Energy.

Luechapattanaporn, Kunchalee; Wang, Yifen; Wang, Jian; Tang, Juming; Hallberg, Linnea M.; Dunne, C. Patrick

BSTRACT: There is a current need for fresh-cooked-like yet shelf-stable egg products for U.S. military combat rations. Novel thermal processes based on radio frequency (RF) energy can shorten the heating time and reduce overheating. This technology was explored to produce shelf-stable egg products for combat ration development. Clostridium sporogenes (PA 3679) spores were used as a surrogate to validate the RF sterilization process to control Clostridium botulinum. Decimal reduction time (D value) of PA3679 in scrambled eggs was determined using aluminum thermal-death-time (TDT) tubes. The thermal inactivation kinetic information was then used in inoculated pack studies to validate a novel thermal process based on 27.12 MHz radio frequency (RF) pilot scale unit. Trays of scrambled eggs inoculated with PA 3679 were subjected to 3 processing levels: target process (F0 about 5.3 min), under-target process (F0 about 3.0 min), and over-target process (F0 about 9.1 min). The results of the microbial challenge study showed that microbial destruction from the RF process agreed with sterilization values calculated from time-temperature data measured at the cold spot in the treated trays. A comparison of RF- and retort-treated scrambled eggs showed significant differences in the degree of lightness ( L*) and redness ( a*). RF-processed egg was less brown compared with conventional retorted eggs. Retort treatment of fully cooked scrambled eggs had higher hardness, springiness, and smaller cohesiveness than RF -treated samples. This study suggests that RF thermal processes can produce safe, shelf-stable sterilized scrambled eggs for both military and civilian uses.

DIELECTRIC heating; RADIO frequency; EGGS as food; SURVIVAL & emergency rations; STERILIZATION (Disinfection); CLOSTRIDIUM botulinum; COOKING

Journal of Food Science (Wiley-Blackwell), 2005, Vol 70, Issue 4, pE288

0022-1147

Academic Journal

10.1111/j.1365-2621.2005.tb07185.x