Fresh or frozen?

posted by admin on 26 September 2012

Earlier this year, we wrote a piece about seafood labeling, discussing the rating systems used to tell consumers whether the fish they are purchasing is from a healthy population and/or caught in an environmentally-friendly way. Recently, the Fish Navy team has been wondering about a different type of labeling: fresh vs. frozen seafood.
 

What does “fresh” mean, anyway? To the unsuspecting consumer, fresh means having just come off the boat, perhaps that morning, fish flopping on the dock mere hours ago.  That’s certainly how the dictionary defines it (“newly or just come or arrived”), even online (“Not cooked, dried or frozen”).  The FDA defines the word fresh in 21 CFR § 101.95  as “food is in its raw state and has not been frozen or subjected to any form of thermal processing or any other form of preservation.”

 
While it shouldn’t be assumed that fishmongers and supermarkets are purposely deceiving their customers, there is confusion that certainly plays in their favor. Some of them label their seafood as “previously frozen” (i.e. not fresh), and others don’t. All the consumer sees is the glistening flesh of delicious fish or shellfish, ready to eat.

 

For example, when buying fresh shrimp, unless you are purchasing them at the dock in Louisiana (or unless you ship them quickly, like this company does), it is likely that they were in fact frozen. Because shrimp tend to spoil quickly, commercial shrimp are usually frozen, either in blocks or through a process known as IQF (“individually quick frozen”).

 

The non-frozen shrimp displayed in markets are in fact thawed. Consumers can have no way of knowing when the shrimp was thawed, which can be a problem if they intend to refreeze them (which is why this isn’t recommended), or to know how long they are still good for. For this reason, it can be actually preferable to buy frozen shrimp (either frozen in blocks or IQF shrimp).

 

IQF is used for many foods, including seafood, meat and produce, to name a few.  It is a preferred method over block freezing because consumers can use only as much of the product as they need, eliminating the need to defrost the whole box. In IQF, the catch is quickly cleaned, spread out (to prevent clumping) and frozen by passing through a sophisticated machine. See a demonstration of the IQF process here:

 

 

The rapid freezing is thought to preserve the texture and moisture of the product, since slow freezing causes cellular damage and moisture loss, which can give a dry, chewy texture when thawed.

 

According to Scott Zimmerman of Safe Quality Seafood Associates, “freshness” is based on the estimated time of harvest and the amount of processing the product has undergone. “The more you mess with it, the quicker it will spoil,” says Zimmerman. A headed and gutted fish has less exposed surface area than a completely filleted fish, so it will have less denaturing of proteins or bacteria and less temperature abuse. How long can the “fresh” headed and gutted fish be called fresh? “Up to a month.” A month. A month under 29 degrees Fahrenheit, but a month nonetheless. A fillet is good for only 2/3 of that time, around 20 days. And if the temperature is above the freezing point, this cuts those shelf lives in half.
 

The go-to freshness standards for quality control professionals is the Seafood Network Information Center.  Aside from set guidelines, quality control agents also undergo organoleptic (sensory) training with NOAA and the FDA, where they learn tell-tale signs for each species. These can include odor, appearance or texture. Labs also test for bacteria, such as coliform and total plate counts.

 

 

Source: http://seafood.ucdavis.edu/pubs/spoils.htm

 

These indicators of freshness are definitely not in line with what most people think of when they think fresh fish. According to Jan Polakow (customer relations for Loblaw Supermarkets), while Gulf shrimp may be a better choice in terms of environmentally sustainable catches, they are thawed twice (once on the boat, then thawed, processed and frozen again) whereas frozen tiger shrimp are only frozen once.
What people don’t realize is that fresh does not mean “recent”, and does not mean “local”, it means “never frozen solid”. Fresh can mean repeatedly warmed and cooled since being caught and killed a month ago on the other side of the world. Ideally, fresh seafood is kept below the freezing point in a brine…ideally. At the high end farms, cold chain control is a big deal. At the smaller operations and on fishing boats…they do the best they can. So the next time you want “fresh”, you may want to consider frozen.

2 thoughts on “Fresh or frozen?

  1. Crystal says

    A new term I encountered while shopping in Seattle’s Pike’s Place Market is “fancy”. When I asked the fishmonger what exactly that meant the response was: “that’s how we label all our previously frozen products”. Not my definition of fancy, that’s for sure.

  2. Danielle says

    Thank you for this blog, so far I’ve been very intrigued by most of the labels. As I love shrimp I’ve tried to buy only fresh with mixed results. This gives me an additional option with great taste.

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