Effects of bacteriophage on the quality and shelf life of Paralichthys olivaceus during chilled storage.
BACKGROUND
The microbiological spoilage of fishery foods is mainly due to specific spoilage organisms (SSOs), with Shewanella putrefaciens being the SSO of most chilled marine fish. Bacteriophages have shown excellent capability to control micro-organisms. The aim of this study was to determine a specific bacteriophage to prevent spoilage by reducing SSO (S. putrefaciens) levels in the marine fish Paralichthys olivaceus (olive flounder) under chilled storage.


RESULTS
Chilled flounder fillets were inoculated with S. putrefaciens and treated with different concentrations of bacteriophage Spp001 ranging from 10(4) to 10(8) plaque-forming units (pfu) mL(-1) . Bacterial growth (including total viable count and SSO) of the bacteriophage-treated groups was significantly inhibited compared with that of the negative control group (P < 0.05). Sensory evaluation and biochemical parameters revealed that the bacteriophage could extend the shelf life of chilled flounder fillets (from <4 to 14 days) with good esthetic quality, even at low temperature (4 °C). Furthermore, bacteriophage concentrations of 10(6) and 10(8) pfu mL(-1) were more effective than the chemical preservative potassium sorbate (5 g L(-1) ).


CONCLUSIONS
The bacteriophage Spp001 offered effective biocontrol of S. putrefaciens under chilled conditions, retaining the quality characteristics of spiked fish fillets, and thus could be a potential candidate for use in chilled fish fillet biopreservation.
Food Safety Laboratory, Ocean University of China, Qingdao, 266003, China.
Meng
M
Li
Hong
H
Lin
Muhammad Naseem
MN
Khan
Jingxue
J
Wang
Linghong
L
Kong
D000818:Animals; D001435:Bacteriophages / Q000502:physiology*; D003080:Cold Temperature; D005432:Flounder; D005516:Food Microbiology; D005519:Food Preservation / Q000379:methods*; D017747:Seafood / Q000382:microbiology*; D020614:Shewanella putrefaciens / Q000821:virology; D013649:Taste; D013997:Time Factors
Paralichthys olivaceus; Shewanella putrefaciens; bacteriophage; chilled storage; food preservation