Date of Award
Doctor of Philosophy
Joseph C. Cordray
Commercially available ham and pork frankfurters were irradiated at 1.6 kGy and evaluated for color, lipid oxidation, odor, flavor and the production of volatiles over 8 weeks of storage. Corned beef, roast beef, beef frankfurters, chicken roll, chicken frankfurters, turkey roll, cured turkey roll and turkey frankfurters were manufactured at the Iowa State Meat Laboratory and irradiated at 1.6 kGy. These products were evaluated for color, odor, flavor, and volatile compounds. Hams were manufactured at the Iowa State Meat Laboratory to achieve three different pHs in the finished products. The hams were treated with 0.0 kGy, 1.21 kGy, 2.34 kGy and 4.57 kGy of irradiation and evaluated for yields, purge lost, color, and volatile compounds. A trained sensory panel evaluated the aroma, off-aroma, flavor, off-flavor, sourness and saltiness of the hams. A consumer panel evaluated the aroma and flavor of the hams;Irradiation processing did not affected the color of any of the products in these studies with the exception of the CIE a* values of the turkey roll. The lipid oxidation values of the commercially available ham and pork frankfurters were not affected at the 1.6 kGy dose. The pH treatments altered the production of volatile compounds in ham including a lipid oxidation product (hexanal) and a sulfur containing compound (carbon disulfide);Irradiation increased the production of volatiles in most of the products included in these studies. The production of dimethyl disulfide increased with the irradiation treatments in all products with the exception of the beef frankfurters. In various products volatile compounds such as 2-methyl butanal, 2-methyl propanal, 1-hexene, 1-heptene were not detected in the control samples but were present in the irradiated samples;The off-odor of the commercially available ham was affected by the 1.6 kGy irradiation treatment. The off-odor scores of the corned beef, roast beef, chicken roll, cured turkey roll, and turkey frankfurters also increased at 1.6 kGy of irradiation. A significant interaction was observed between pH and irradiation treatment for flavor scores of ham. The trained panelists detected significant differences in flavor between the non-irradiated samples at pH 6.72 and 6.36 when compared to the non-irradiate samples at pH 5.82. However, the panel reported no significant differences in flavor scores between the low and high pH hams when the product was treated with 2.34 kGy of irradiation. The consumers included in this study reported significantly lower aroma and flavor scores for the irradiated samples.
Digital Repository @ Iowa State University, http://lib.dr.iastate.edu
Wigberto Núñez Maisonet
Núñez Maisonet, Wigberto, "Irradiation processing of ready-to-eat meats" (2005). Retrospective Theses and Dissertations. 1323.