The physical, chemical and microbial effects of supplemental sodium nitrate on cured meat products
The effects of supplemental nitrate from celery powder on boneless ham, cotto salami and frankfurters were investigated. Two treatments (control and supplemental nitrate) of each product were replicated twice to evaluate residual nitrite, residual nitrate, rancidity, microbial growth, color, sensory properties, and proximate composition. All analytical measurements were conducted at regular intervals for 98 days during storage at 1°C (32 − 34°F). Residual nitrite values were not significantly different (P > 0.05) between treatments for cotto salami and hams, however, for frankfurters the control (15.8 ppm) and supplemental nitrate (11.9 ppm) treatments were significantly different (P < 0.05). Residual nitrate values were significantly different (P < 0.05) between the two treatments for all three products as expected; however, the residual nitrate values for each treatment were not significantly different (P > 0.05) for the effect of day. Rancidity (TBARS) was significantly different (P < 0.05) for cotto salami control (0.47) and supplemented cotto salami treatment (0.37), as well as the frankfurter control (0.38) and the supplemented frankfurter treatment (0.49). However, no statistical difference (P > 0.05) in rancidity was observed between the two ham treatments. The results also showed no statistical difference (P > 0.05) for microbial growth between the treatments for any of the products. Color measurements showed that Hunter L-values for the cotto salami control (49.65) and the supplemented cotto salami (46.94) were significantly different (P < 0.05), and Hunter a-values for the ham control (8.59) and the supplemented ham (7.92) were also significantly different (P < 0.05). The internal color measurement of Hunter a-values for frankfurters determined that the control treatment (10.62) displayed a significantly different (P < 0.05) Hunter a-value than the supplemental nitrate treatment (10.11). None of the other physical, chemical or microbial measurements conducted were different as a result of the treatments. Sensory evaluations (15 cm line scale) supported the instrumental color results for cotto salami, frankfurters, and ham treatments. Sensory panel scores showed frankfurter (9.33) and ham (9.86) control treatments displayed a greater intensity of pink color than the frankfurter (6.93) and ham (6.56) supplemental nitrate treatments. Panelists determined the control cotto salami (6.65) treatment had a lighter visual appearance than the supplement nitrate cotto salami (9.87) treatment. Frankfurters showed no differences for sensory panel odors or flavors while the treatments for cotto salami resulted in some differences in aromas and flavors, and the greatest effect on aroma and flavor occurred with the hams. Consequently, the results showed that the overall addition of supplemental nitrate did not significantly alter physical, chemical or microbial effects on cured meat products during refrigerated storage, but some product-dependent sensory effects were observed.