For decades now, freezing is recognized as one of the most effective conservation systems in the treatment of fresh food, also offering the enormous advantage of keeping intact all the nutritional values of the product. The basic mechanism of the use of cold for this purpose is easily explained: at low temperatures, the speed of changes that spoil raw materials is sharply reduced while, on the other hand, most microorganisms responsible for infections or poisoning also paralyze their growth. Currently, the most widely used method for commercial purposes is deep-freezing, which consists of achieving a temperature between -18 ° C and -20 ° C until product’s final consumption.
Modern food market depends (in a large percentage) on frozen products, which also enable another relevant practice: to space our purchases, thus saving time and theoretically stabilizing prices, since all products can be marketed during their optimal harvest time.
If there is nothing but advantages, what’s the danger, then? Major concern for producers, distributors and sellers (and users, of course) is that the so-called Cold Chain can get broken. This term designates the linear system formed by each of the steps that constitute the process of cooling (or freezing) necessary for perishable foods -such as fish and sea fruit- to arrive safely to the final consumer. This includes an absolutely controlled handling of all values regarding temperature and humidity of these items, which are very sensitive to environmental conditions. If there is any minimally significant change at some point during this long process, ranging from production of the product (or fishing, in this case), its transportation, storage and final sale; that is, if this security temperature range is broken up in any of these stages, the product inevitably degrades and loses its sensory properties (smell, flavour and taste), as well as becoming a true hazard to public health. That’s because of the fact that when we lose the protection of the freezing process, all microbiological activity resumes at an accelerated pace and the quality loss of fresh products is already irreversible, making it impossible to be properly preserved. That’s why these kind of food must be thawed at a moderate speed and cooked to be eaten just after, but can never go through a second freezing operation.
In the fish and seafood market -products that are especially susceptible to these alterations in temperature- all these factors endow a greater relevance to the need of maintaining a special zeal in ensuring that this ongoing process -this “cold chain” – is not altered at any time, either by food professionals or consumers. The latter have to duly take it into account, especially when it comes to knowing what products are dealing with and how to cook them, in addition to make sure that they buy from a reliable source that guarantees this cold chain has never been interrupted or altered in any way.