Microbiological and biochemical changes in pearl spot (Etroplus suratensis Bloch) stored under modified atmospheres.
OBJECTIVE
This study aimed to determine the effect of packaging [air, modified atmosphere (MA)] on microbial growth, sensory and chemical parameters and also on shelf life of fresh pearl spot (Etroplus suratensis Bloch) and on the selection of microbial association.


RESULTS
Fresh pearl spot (whole, gutted) were packaged under both 100% air and MAs (40%CO(2)/60% O(2), 50%CO(2)/50%O(2), 60% CO(2)/40%O(2), 70% CO(2)/30% O(2) and 40% CO(2)/30% O(2)/30% N(2)) and stored at 0 degrees C. Microbial growth (counts of total aerobic bacteria, H(2)S-producing bacteria, Lactic acid bacteria, Brochothrix thermosphacta, yeast and mould), chemical spoilage indicators (pH, total volatile basic nitrogen) and sensory characteristics were monitored. Microbial changes in Pearl spot packed under 100% air and 40% CO(2)/30%O(2)/30% N(2) were similar. The total volatile basic nitrogen values increased, but the values never exceeded the acceptability limit of 25 mg 100 g(-1).


CONCLUSIONS
MA 60% CO(2) : 40%O(2) was found to be better with a shelf life of 21 days whereas air stored samples had a shelf-life of 12-14 days only.


CONCLUSIONS
Storage of pearl spot under MAs 60% CO(2) : 40%O(2) is a promising method to extend shelf-life. Longer shelf life expands the market potential of pearl spot and reduces waste during distribution and retail display.
Lalitha
K V
KV
Cental Institute of Fisheries Technology, Cochin, India. lalithakv@hotmail.com
Sonaji
E R
ER
Manju
S
S
Jose
L
L
Gopal
T K S
TK
Ravisankar
C N
CN
D000332:Aerobiosis / Q000502:physiology; D000818:Animals; D001419:Bacteria / Q000254:growth & development; D002245:Carbon Dioxide / Q000502:physiology; D015169:Colony Count, Microbial / Q000379:methods; D005399:Fishes / Q000382:microbiology*; D005511:Food Handling / Q000379:methods*; D005516:Food Microbiology; D006862:Hydrogen Sulfide / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D009584:Nitrogen / Q000032:analysis / Q000502:physiology; D010100:Oxygen / Q000502:physiology; D012677:Sensation / Q000502:physiology
D002245:Carbon Dioxide; D009584:Nitrogen; D010100:Oxygen; D006862:Hydrogen Sulfide