Shelf life and safety aspects of chilled cooked and peeled shrimps (Pandalus borealis) in modified atmosphere packaging.
OBJECTIVE
To evaluate the growth of Listeria monocytogenes and shelf life of cooked and peeled shrimps in modified atmosphere packaging (MAP).


RESULTS
Storage trials with naturally contaminated cooked and peeled MAP shrimps (Pandalus borealis) were carried out at 2, 5 and 8 degrees C. Challenge tests at the same conditions were performed after inoculation with Listeria monocytogenes. Both storage trials and challenge tests were repeated after 4 months of frozen storage (-22 degrees C). Brochothrix thermosphacta and Carnobacterium maltaromaticum were responsible for sensory spoilage of cooked and peeled MAP shrimps. In challenge tests, growth of L. monocytogenes was observed at all of the storage temperatures studied. At 5 and 8 degrees C the concentration of L. monocytogenes increased more than a 1000-fold before the product became sensory spoiled whereas this was not observed at 2 degrees C. Frozen storage had only a minor inhibiting effect on growth of L. monocytogenes in the thawed product.


CONCLUSIONS
To prevent L. monocytogenes becoming a safety problem, cooked and peeled MAP shrimps should be distributed at 2 degrees C and with a maximum shelf life of 20-21 d. At higher temperatures shelf life is significantly reduced.


CONCLUSIONS
Information is provided to establish shelf life of cooked and peeled MAP shrimps.
Mejlholm
O
O
Department of Seafood Research, Danish Institute for Fisheries Research (DIFRES), Lyngby, Denmark. ome@dfu.min.dk
Bøknaes
N
N
Dalgaard
P
P
D015169:Colony Count, Microbial / Q000379:methods; D003296:Cooking; D005511:Food Handling / Q000379:methods*; D005516:Food Microbiology; D018857:Food Packaging / Q000379:methods; D005519:Food Preservation / Q000379:methods; D005615:Freezing; D006094:Gram-Positive Bacteria / Q000254:growth & development; D008089:Listeria monocytogenes / Q000254:growth & development*; D008954:Models, Biological; D033542:Pandalidae / Q000382:microbiology*; D012449:Safety; D017747:Seafood / Q000382:microbiology*; D013997:Time Factors