Microbiology and HACCP For Surimi Seafood

Surimi Seafood Microbiology Production and storage Microbial quality Microbial safety Pasteurization studies Non-thermal processing HACCP Microbial standards Packaging Fermented products Rapid test kits

Microbiology of Surimi During Production and Storage

Microbial Quality and Safety of Surimi Seafood Depends On: Microbial load in the raw surimi Microbial load in ingredients Processing time/temperature abuse Equipment sanitation Employee hygiene

a = surimi b = surimi plus ingredients c = first cook/rope formation d = color addition e = second cook f = flaking or chopping g = packaging h = “pasteurization”

a = surimi b = surimi plus ingredients c = first cook/rope formation d = color addition e = second cook f = flaking or chopping g = packaging h = pasteurization

a = surimi b = surimi plus ingredients c = first cook/rope formation d = color addition e = second cook f = flaking or chopping g = packaging h = pasteurization

Equipment Sanitation Belt conveyor1,800,000/cm 2 Container of mixed paste25,000/cm 2 Inner wall of mixer540/cm 2

Surimi Seafood Shelf Life Days at:15 o C10 o C5 o C0 o C 59 o F50 o F41 o F32 o F Surimi crab legs414>28>28 Flaked surimi crab meat<3<4<714

Microbial Quality of Surimi Seafood: Bacillus Species and Other Gram-positive Bacteria

Pasteurization Has no effect on bacterial spores, i.e., Clostridium and Bacillus species Bacillus species are prime spoilers in air- packaged surimi seafood

Microbial Safety of Surimi Seafood: Listeria monocytogenes, Clostridium botulinum and Other Bacteria

L. monocytogenes 1988 surimi survey found 29% of samples positive 1988 U.S. Class I recall of imitation crab meat produced in Japan and distributed in three states

Table 1. Surimi Seafood Recalls Due to L. monocytogenes Imitation crab meat products7/28/99 Imitation crab spread9/17/97 Imitation king crab legs8/6/97 Imitation crab meat chunks6/12/96 Imitation crab meat salad9/30/92 Seafood salad7/2/92

Clostridium botulinum Strict anaerobe Grows above 38°F No instances reported from surimi seafood C. botulinum type E and nonproteolytic types B and F are the target bacteria for FDA’s pasteurization processes – 6-D process = 90°C (194°F) for 10 minutes

Generation Times (Hours) for Pathogens in Surimi Seafood 15 o C10 o C5 o C0 o C 59 o F50 o F41 o F32 o F Aeromonas hydrophila Salmonella species Staphylococcus aureus Yersinia enterocolitica

Pasteurization Studies for Surimi Seafood Inoculated pack studies with Enterococcus faecium – 93°C (199.4°F) 5 minutes – 85°C (185°F) for 15 minutes – 75°C (167°F) for 15 minutes Yielded 6 log reduction of E. faecium – Process also effective against C. botulinum Type E (85 and 93°C), L. monocytogenes, enteropathogenic E. coli, Salmonella, Yersinia entercolitica, and Vibrio Ineffective against C. botulinum Type B

Pasteurization Studies for Surimi Seafood TemperatureTimeD-Values (min.)L.m.C.b.(E)C.b.(B) 93°C (199.4°F) 516, °C (185°F) 155, °C (167°F)

Microbiological Implications of Novel Surimi Processing Technologies High pressure – MPa – Effective against Vibrio, Listeria, Salmonella – Ineffective against pressure resistant species and spore forming Bacillus and Clostridium species Electron beam – Untested

HACCP and Surimi Seafood Preventive system of food safety control Based on – Identified hazards – Critical control points – Monitoring records

Metal Fragments Hard or sharp objects >7 mm in size are a potential hazard from laceration, perforation wound, and secondary infections Hard or sharp objects <7 mm in size are a possible hazard for high risk (e.g., infants, elderly) individuals Controls can include frequent inspections of cutting, portioning, blending, or other mechanical equipment for damage, or use of a metal detector

Pasteurization Eliminates targeted pathogenic bacteria and also extends product shelf life Pathogens in packaged products indicates inadequate pasteurization, or post pasteurization contamination, and time/temperature abuse Critical aspects: temperature of heating medium, length of pasteurization cycle, package thickness, package integrity, product formulation, and microbial quality of the cooling medium

Cooling Rapid cooling prevents growth from Bacillus and Clostridium 60°C (140°F) to 21.1°C (70°F) in 2 hours To 4.4°C (40°F) within another 4 hours

Refrigerated Storage Refrigerated storage below 4.4°C (40°F) prevents growth of pathogens

Microbial Recommendations for Ready-to-eat Seafood ncmM Aerobic plate count E. coli S. aureus V. parahaemolyticus

FDA Tolerance Levels: Vacuum Packaged Ready-to-eat Seafood C. botulinumPresence of cells, Enteropathogenic E. coli10 3 /g L. monocytogenesPresence SalmonellaPresence S. aureus10 4 /g or toxin positive V. choleraePresence V. parahaemolyticus10 4 /g V. vulnificusPresence

Microbiological Considerations in Packaging of Surimi Seafood Nitrogen and carbon dioxide packaging reduce fat and pigment oxidation and reduce spoilage bacterial growth Aseptic packaging requires a sterile product and may not be feasible

New Surimi Seafood Products Utilizing Fermentative Bacteria Fermented pollock kamaboko – pH 4.5 – Sour tasting Fermented chum salmon surimi Sensory studies have not been conducted

Reliability and Efficacy of Rapid Microbiological Procedures Traditional methods – APC with petri dishes or PetriFilm Rapid test kits for L. monocytogenes – 1-2 days instead of 5-7 days

Conclusion Surimi seafood Products are ready-to-eat – Safety and quality concerns remain – HACCP can help ensure a safe product The use of the term “pasteurization” should be discouraged or the process needs to be further studied