Improved antimicrobial activity of nisin-incorporated polymer films by formulation change and addition of food grade chelator.
OBJECTIVE
The following polymers were developed: polyethylene (PE), a PE and polyethylene oxide (70% PE and 30% PEO; PE + PEO) blend, PE and nisin (PE + nisin), PE, nisin, and EDTA (PE + nisin + EDTA), and PE + PEO with nisin (PE + PEO + nisin).


RESULTS
Of the polymers tested, PE and PE + PEO did not exhibit any antimicrobial activity against Brochothrix thermosphacta (BT); however, PE + nisin, PE + nisin + EDTA, and PE + PEO + nisin did. Beef surfaces were experimentally inoculated with 3.50 log10 cfu/cm2 of BT, vacuum packaged with each of the five polymers, and held at 4 degrees C for 21 d. After 3 d at 4 degrees C, BT was reduced > 1.70 log(10) by PE + nisin and > 3.50 log(10) with PE + nisin + EDTA or PE + PEO + nisin. By 21 d at 4 degrees C, BT was reduced to 0.30 log(10) cfu/cm(2) when treated with PE + PEO + nisin.


CONCLUSIONS
It appears that PE + PEO + nisin or PE + nisin + EDTA were more effective for reducing BT, as compared to polymers composed of PE + nisin.


CONCLUSIONS
Nisin-incorporated polymers may control the growth of undesirable bacteria, thereby extending the shelf life and possibly enhancing the microbial safety of meats.
Cutter
C N
CN
United States Department of Agriculture, Agricultural Research Service, Roman L. Hruska U.S. Meat Animal Research Center, PO Box 166, Clay Center, NE 68933, USA. cnc3@psu.edu
Willett
J L
JL
Siragusa
G R
GR
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002614:Chelating Agents / Q000494:pharmacology*; D002626:Chemistry, Pharmaceutical; D004492:Edetic Acid / Q000494:pharmacology; D005506:Food Contamination / Q000517:prevention & control; D005516:Food Microbiology; D005519:Food Preservation / Q000379:methods; D006093:Gram-Positive Asporogenous Rods / Q000187:drug effects* / Q000254:growth & development; D008460:Meat / Q000382:microbiology*; D009561:Nisin / Q000494:pharmacology*; D011108:Polymers / Q000737:chemistry / Q000494:pharmacology*
D000900:Anti-Bacterial Agents; D002614:Chelating Agents; D011108:Polymers; D009561:Nisin; D004492:Edetic Acid