One of the most common mistakes I’ve come across in sushi and sashimi businesses is misunderstanding on how the freezing requirements for parasite control actually work.
Many food businesses believe the required freezing time starts as soon as fish is placed into the freezer. This is not the case for fish that is exempt from freezing for parasitic control or has supplier documentation confirmation for parasitic destruction.
In reality, the timing only begins once the fish itself has reached the required frozen temperature.
This is an important distinction because large fish portions, tuna loins, salmon sides, or heavily loaded freezers can take many hours to fully freeze internally. If businesses start counting the hours too early, the fish may never complete the required parasite destruction treatment. That customer who complains about seeing a live parasite in their sashimi may actually be correct and they may report the business to the council EHO department.
Eating live parasites found in fish cause a parasitic infection called Anisakiasis. This happens when parasites such as Anisakis survive in fish that has not been properly frozen and is then served raw for consumption.
Symptoms can include:
- severe stomach pain
- nausea
- vomiting
- diarrhoea
- abdominal cramps
- allergic reactions in some cases
Symptoms may begin within hours after eating contaminated fish. In some cases, the parasite can attach to the stomach or intestinal lining and require medical removal by endoscopy.
Legal freezing controls are designed to destroy parasites that may be present in certain fish intended for raw consumption. Simply placing fish into a freezer is not enough. Proper freezing controls for sushi and sashimi fish are designed to destroy these parasites before the fish is served raw and prevent consumers eating live parasites.
The product must:
- reach the required temperature
- remain at that temperature for the validated time period
Common problems include:
- overloading freezers
- using domestic freezers without validation
- freezing large fish portions
- failing to monitor core temperatures
- inaccurate record keeping
These issues can result in unsafe food and potential non-compliance during inspections.
Good practice should include:
- validated freezing procedures
- understanding freezer performance
- accurate timing records
- staff training on parasite destruction requirements
For sushi and sashimi businesses, specialist food safety knowledge is essential. Generic food hygiene training often does not adequately cover raw fish parasite controls and freezing validation requirements.
Understanding when freezing time actually begins is a simple but critical part of serving raw fish safely.
If your business prepares or sells sushi, sashimi, ceviche, or other raw fish products, we provide specialist sushi and sashimi food safety training, raw fish hygiene training, and expert HACCP plan development for businesses across the UK. Contact our experienced sushi and sashimi food safety consultants to discuss your requirements.
We also offer self-paced eLearning at level 2 specifically for sushi and sashimi, which you can find under courses or click Sushi and Sashimi Food Safety Training Course
Written by Carren Amoli B.Sc. (Hons)
