Ao. Gill et Ra. Holley, Surface application of lysozyme, nisin, and EDTA to inhibit spoilage and pathogenic bacteria on ham and bologna, J FOOD PROT, 63(10), 2000, pp. 1338-1346
A study was conducted to determine if the effectiveness of an antimicrobial
treatment for cooked ham and bologna would be increased or maintained when
applied in a surface coating. Cooked 10-g disks of ham and bologna sausage
received one of three treatments: no coating (control), coating with 0.2 g
of 7% (wt/vol) gelatin gel (gel-control), or coating with 0.2 g of 7% gela
tin gel containing 25.5 g/liter of lysozyme-nisin (1:3) plus 25.5 g/liter o
f EDTA (gel-treated). The samples were then inoculated with one of six test
organisms: Brochothrix thermosphacta, Escherichia coli O157:H7, Lactobacil
lus sakei, Leuconostoc mesenteroides, Listeria monocytogenes, or Salmonella
Typhimurium. Inoculated samples were vacuum packed and stored at 8 degrees
C for 4 weeks. The antimicrobial gel treatment had an immediate bactericid
al effect up to 4 log CFU/cm(2) on the four gram-positive organisms tested
(B. thermosphacta, Lactobacillus sakei, Leuconostoc mesenteroides, and List
eria monocytogenes) and inhibited the growth of these organisms during the
4 weeks of storage. The antimicrobial gel treatment also had a bactericidal
effect on the growth of Salmonella Typhimurium during storage. The numbers
of E. coli O157:H7 on ham were reduced by 2 log CFU/cm(2) following treatm
ent with both antimicrobial-containing and non-antimicrobial-containing gel
s during the 4-week storage period. No effect was observed on the growth of
E. coli O157:H7 on bologna.