Effectiveness of Potassium Lactate and Sodium Diacetate in Combination with Irradiation to Control Listeria monocytogenes on Frankfurters

Abstract

The use of antimicrobial ingredients in combination with irradiation is an effective antilisterial intervention strategy for ready-to-eat meat products. Microbial safety was evaluated for frankfurters formulated with 0% or 3% added potassium lactate/sodium diacetate solution and inoculated with Listeria monocytogenes before or after treatment with irradiation (0, 1.8, or 2.6 kGy). Frankfurters were stored aerobically or vacuum packaged and L. monocytogenes counts and APCs were determined while refrigerated. The incorporation of lactate/diacetate with or without irradiation had a strong listeriostatic effect for aerobically stored frankfurters. Outgrowth was suppressed and counts were not different from initial counts (5.2 log CFU/frank compared with 5.0 log CFU/frank); however, those without the additive increased steadily (5.4 to 9.3 log CFU/frank). Irradiation treatments alone had higher L. monocytogenes counts after 3 wk. For vacuum-packaged frankfurters, both the addition of lactate/diacetate and irradiation were effective at controlling growth after 8 wk. Large and incremental reductions in total counts were seen for irradiation treatments. Initial counts were reduced by 3 log CFU with the application of 1.8 kGy while 2.6 kGy decreased counts over 5 log CFU. These reductions were maintained throughout storage for lactate/diacetate-treated frankfurters. By 8 wk, L. monocytogenes counts on 1.8 and 2.6 kGy irradiated frankfurters without lactate/diacetate increased to 7.43 and 6.13 log CFU, respectively. Overall, lactate/diacetate retarded the outgrowth of L. monocytogenes on frankfurters throughout aerobic storage and the combination of irradiation and 3% lactate/diacetate reduced and retarded growth of L. monocytogenes, especially during the last 2 wk of vacuum-packaged storage.

Inactivation of Foodborne Pathogens on Frankfurters Using Ultraviolet Light and Gras Antimicrobials

“…For the UV-C-treated frankfurters, an initial drop in viable pathogens was observed, followed by a recovery during the 12 week storage period for L. monocytogenes and S. aureus. Similar results were observed for L. monocytogenes and S. aureus inoculated into sausages and frankfurters containing SDA and PL when sublethal doses of ionizing radiation were applied, followed by storage at 10C (Seman et al 2002;Sommers et al 2003;Sommers and Boyd 2006;Knight et al 2007). The use of SDA, PL and LAE in combination resulted in decreases for all three pathogens; however, the cfu/g of L. monocytogenes and S. aureus leveled off between weeks 8 and 12.…”

Effect of liquid smoke as an ingredient in frankfurters on Listeria monocytogenes and quality attributes

“…Porto et al (2002) indicated that the use of 2 or 3% potassium lactate as an ingredient had a listeriostatic effect on frankfurters inoculated with either 20 or 500 cfu L. monocytogenes over a 90-d vacuum storage period at 4°C. Knight et al (2007) combined sodium lactate and diacetate treatment with irradiation of frankfurters that resulted in retarding the growth of Listeria from wk 6 to 8 during the 8-wk storage period.…”

Antilisterial effects of different hop acids in combination with potassium acetate and potassium diacetate at 7 and 37 °C

“…The antilisterial efficacy of these acids is affected by many factors such as pH, water activity, nitrite, salt content, storage conditions, and other inhibitor components (Legan, Seman, Milkowski, Hirschey, & Vandeven, 2004;Samelis et al, 2003;Seman, Borger, Meyer, Hall, & Milkowski, 2002). Improvement of antilisterial activity has been reported by mixing these organic acids with other inhibitors including hop acids (Barmpalia et al, 2004;Knight, Castillo, Maxim, Keeton, & Miller, 2007;Shen & Sofos, 2008;Zhu, Mendonca, Ismail, & Ahn, 2009). …”