title: Effect of potassium lactate and a potassium lactate-sodium diacetate blend on Listeria monocytogenes growth in modified atmosphere packaged sliced ham.
abstract: Two commercially available organic acid salts, potassium lactate (PURASAL HiPure P) and a potassium lactate-sodium diacetate blend (PURASAL Opti. Form PD 4), were assessed as potential inhibitors of Listeria monocytogenes growth in modified atmosphere packaged (MAP) sliced ham in challenge studies. The influence of the initial inoculation level of L. monocytogenes (10(1) or 10(3) CFU g(-1)) and storage temperature (4 or 8 degrees C) was also examined. The addition of either organic acid salt to MAP sliced ham strongly inhibited the growth of L. monocytogenes during the normal shelf life of the product under ideal refrigeration conditions (4 degrees C) and even under abusive temperature conditions (i.e., 8 degrees C). During the challenge studies and in the absence of either organic acid salt, L. monocytogenes numbers increased by 1000-fold after 20 days at 8 degrees C and 10-fold after 42 days at 4 degrees C. Both organic acid salt treatments were found to be listeriostatic rather than listericidal. The addition of either organic acid salt to the MAP ham also reduced the growth of indigenous microflora, i.e., aerobic microflora and lactic acid bacteria. The influence of these compounds on the risk of listeriosis in relation to product shelf life is discussed.
authors.affiliation: Australian Food Safety Centre of Excellence, Tasmanian Institute of Agricultural Research, School of Agricultural Science, University of Tasmania, Private Bag 54, Hobart 7001, Tasmania, Australia. lyndal.mellefont@utas.edu.au
authors.forename: L A
authors.initials: LA
authors.lastname: Mellefont
authors.forename: T
authors.initials: T
authors.lastname: Ross
mesh_terms: D000818:Animals; D015169:Colony Count, Microbial; D005506:Food Contamination / Q000032:analysis*; D005511:Food Handling / Q000379:methods; D005516:Food Microbiology; D018857:Food Packaging / Q000379:methods*; D005519:Food Preservation / Q000379:methods; D005520:Food Preservatives / Q000494:pharmacology*; D006801:Humans; D007773:Lactates / Q000494:pharmacology; D008089:Listeria monocytogenes / Q000187:drug effects* / Q000254:growth & development; D008461:Meat Products / Q000382:microbiology*; D012478:Salmonella Food Poisoning / Q000453:epidemiology / Q000517:prevention & control; D019346:Sodium Acetate / Q000494:pharmacology; D013552:Swine; D013696:Temperature; D013997:Time Factors
chemical_list: D005520:Food Preservatives; D007773:Lactates; D019346:Sodium Acetate