Frankfurters were manufactured to contain certain combinations of curing ingredients (sodium nitrite, sodium nitrate and DL alpha-tocopherol). Some frankfurters were made to contain in the finished product 0% added moisture, others were made to contain 10% added moisture, some frankfurters were not irradiated (0-megarad), others were irradiated with either 0.8 or 3.2 megarads (Cobalt-60 radiation source). Use of DL, alpha-tocopherol (at a level of 206 ppm) was associated with greater processing shrinkage, more off-flavor and less overall palatability (P<0.05). The most desirable external and internal cured color and firmest texture was in frankfurters made with 50 ppm of NO2 or with 100 ppm of NO2, irrespective of irradiation level. Use of irradiation (0.8 or 3.2 megarads) on frankfurters made without nitrite or nitrate did not improve visually determined cured color but did improve this color when determined spectrophotometrically; nevertheless, cured color of irradiated frankfurters made without use of nitrite or nitrate was not comparable to that of non-irradiated or irradiated frankfurters made with 100 ppm NO2. Irrespective of added moisture or curing ingredient combinations, significant differences (P<0.05) in palatability traits were associated with increasing irradiation levels (0, 0.8 or 3.2 megarads). Off-flavor increased, texture was less firm and overall palatability was less desirable as irradiation level increased. Low-dose irradiation (⩽1 megarad) may be feasible for enhancing the palatability traits of frankfurters containing lower levels of nitrite (lower than 156 ppm) but it appears that the correct irradiation level would be lower than the 0.8 megarad used in this study.
1Texas A & M University.
2U.S. Army Natick Research and Development Command.