Freezing Control in Raw Fishery Products
Scientific Evidence and Technologies that Safeguard Safety
The consumption of raw fishery products is associated with specific biological hazards, the most significant being the presence of nematode larvae of the genus Anisakis. Since these products do not undergo any heat treatment, their safety depends entirely on the effective inactivation of parasites through freezing and on the maintenance of an uninterrupted cold chain.
From Legislation to Practice
According to Regulation (EC) 853/2004, fishery products intended to be consumed raw or almost raw must be frozen at -20°C for at least 24 hours or at -35°C for 15 hours, in order to ensure they are free from parasites as required. This specification refers not to the air temperature, but to the temperature of the product itself, which must be achieved throughout the entire fish portion. The scientifically accurate interpretation is that the required temperature must reach and be maintained at the thickest part (core) of the product, i.e. the point that cools at the slowest rate and is the critical factor for the successful inactivation of parasites.
Anisakiasis: Health Risks When Freezing Is Not Done Properly
Improper application of the freezing process allows Anisakis larvae to survive, which can lead to anisakiasis. The clinical picture of the disease includes two main forms:
- gastrointestinal invasion, with sudden abdominal pain, nausea and vomiting, and
- immunological hypersensitivity, which may present as urticaria or, in rare cases, as anaphylactic reaction.
Correct application of freezing is the only effective preventive measure.
Why Manual Checks Are Not Enough
Compliance cannot be adequately documented through handwritten or occasional temperature measurements, as these capture only momentary values and fail to reveal potential temperature fluctuations or interruptions in the freezing process. For products that do not undergo any further heat treatment, the continuous achievement and maintenance of the required temperature is a non-negotiable safety prerequisite.
Smart Temperature Data-loggers
In this context, modern temperature data loggers, like HAM ThermoSense, are an essential tool for businesses handling raw fishery products. With 24/7 continuous recording, automatic alerts, storage of temperature history and central monitoring of multiple refrigeration units, such systems provide objective evidence of compliance with Regulation (EC) 853/2004.
Adopting these technologies is no longer a luxury, but a necessity for any modern food service business that uses raw fishery products. Ensuring that the freezing process is applied without any deviation protects public health, strengthens the business’s credibility, and constitutes a fundamental element of responsible and scientifically substantiated operation.
About the Author: Anastasia Panagopoulou is a Food Technologist and Quality Consultant, member of P.E.T.E.T., specializing in food safety, HACCP systems, and risk management in catering and production companies.
Contact info: [email protected] , (+30) 695 1700 480