Purpose: Validate efficacy of buffered vinegar (BV) or a blend of potassium lactate and sodium diacetate (KLac) to control Lm on mortadella, a specialty luncheon meat.
Methods: All-pork, mortadella was produced by a local butcher with or without 1.0 or 1.5% of liquid BV (LBV), 0.6 or 1.0% of dry BV (DBV), or 2.5% of KLac. In each of three trials, mortadella was sliced (ca. 1.5 cm thick, ca. 30 g) and surface inoculated with 250 µl per side of a five-strain mixture of Lm (ca. 3.8 log CFU/slice). The packages were vacuum-sealed and then stored at 4° or 12°C for up to 120 days.
Results: In the absence of antimicrobials, Lm numbers increased by ca. 2.3 and 5.7 log CFU/slice after 120 days at 4° and 12°C, respectively. With inclusion of 1.0 or 1.5% LBV, 1.0% DBV, or 2.5% KLac as ingredients, pathogen numbers decreased by ca. 0.4 to 1.0 log CFU/g after 120 days at 4°C, whereas inclusion of 0.6% DBV resulted in a ca. 0.2-log CFU/slice increase in Lm numbers. At 12°C, inclusion of 2.5% KLac, 1.0% LBV, or 0.6% DBV resulted in a ca. 1.3-, 1.7-, and 4.5-log increase in Lm numbers, respectively. However, when 1.5% LBV or 1.0% DBV were included in the formulation, pathogen numbers decreased by ca. 0.3 and 1.5 log CFU/slice, respectively, after 105 days, but product quality was lessened at this abusive storage temperature.
Significance: Inclusion of 1% LBV or DBV, as clean label ingredients, in mortadella is equally effective as 2.5%KLac (1.0 log reduction) to control Lm on mortadella during proper storage.