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Frozen is Fresh
  1. Let me clarify couples of things before we get to the actual subject.
  2. At Catamaran this is our classification of fish based on it state/temperature
  3. Live - The fish is alive and kicking, no temperature control is required
  4. Fresh - We got the fish live, however it died after it came to us and it is less than 4 hours since it died - Best quality ever to eat. Live is not as good as this one.
  5. Chilled- - We are not sure when the fish died, however, the fish is in good condition and has consistently been stored at a temperature between 2 Degrees to 4 Degrees centigrade.
  6. Frozen - We do not know when the fish died, however the fish is in good condition and has been frozen using Blast Freezing or Individually Quick Freezing techniques at temperatures less than - 40 degrees centigrade, and stored consistently at - 18 and below.
  7. Dry - A lot of questions like when it died, what temperature and storage are irrelevant. Almost 0 moisture content.
Now please read the article on “What happens after fish dies” before reading further

Assuming you have read it, the best stage to eat fish is when it is in rigor mortis. However what you generally get to eat is chilled fish and unless you have a mobile laboratory with you and you have the personal ability to pathologically verify the stage at which the fish is in, there is no way you would be able to identify. Unless the fish is putrefying there is no way you would be able to identify with your eyes and nose that the fish is bad. So it is possible that you end up eating fish which is in autolysis stage or early putrefaction stage. Now if you do unfortunately end up eating a fish which is in putrefaction stage (it is not necessary that it will smell at this stage), there is a very high probability that you would end up in hospital with rashes, diarrhea and or decentry. Then how do you ensure that you do not eat fish that is not good for you?

  1. Eat fish that died in front of you
  2. Eat chilled fish from a very reliable vendor, who you know is HACCP compliant
  3. Eat Frozen
It is difficult to do the first one all the time for all varieties, I am not too sure if you can find lot of retailers who can offer you the second (hotels can generally forget about this option for the kind of quantities they would need), hence the third is the best and easiest.

Now the next question you have in your mind is Why. This is Why.

  1. Freezing is one of the ways of preserving fish and arresting the post death stages triggers.
  2. The sanctity of freezing at -40 and below is because at - 18 and below all chemical reactions in the fish stop and at - 38 and below all enzymatic reactions stop. Which means once the fish is blast frozen or individually quick frozen, all the chemical and enzymatic reactions get stopped and therefore the quality of the fish will remain where ever it was with out deteriorating. This means if a fish is frozen when it is in rigor mortis stage, it will remain in that stage until it is brought to the room temperature.
  3. All the plants that have the blast freezing or IQF capabilities are HACCP compliant and some of them are EU compliant, which means they are very careful about selecting the raw material which in turn means it is either in the rigor mortis stage or at best in autolysis stage, which in turn means it is good for consumption. Hence Frozen IS Fresh.
  4. The same cannot be guaranteed about a fish which is in chilled form. The temperature of that fish could have been brought up and then again brought down. It is not uncommon in Indian scenario where no quality compliance laws are mandatory, hence my recommendation to buy from a retailer who is HACCP compliant.
The second aspect or reason as to why frozen is fresh and this is more applicable to hotels and I am also hoping will help dispel the illusions people have about frozen.

  1. When someone refers to frozen we are quick to imagine a typical ice cream freezer in which something chilled is kept to freeze. Later one fine day when you want to eat it, you take that out, thaw, cook and eat, it almost tastes insipid. There is nothing wrong in your perception or experience. Its just that, the frozen I am referring to is not actually frozen the way you just imagined, but rather it is quick frozen as in frozen under temperatures less than - 40 degrees centigrade and if you are referring to Sashimi grade tuna, it is frozen at temperatures less than - 80 degrees centigrade.
  2. However, what hotels do is exactly the same as the ice cream freezer example. They receive the chilled product and instead of putting it in a chiller actually store it in a -18 deep.
  3. Take an apple, put it in the deep freezer of your home refrigerator where you make ice and leave it overnight. Next day morning, try eating it for breakfast. Along with the apple leave a silicon glass bottle full of water. Let me know what happened to both these items.That is exactly what will happen to your fish fillet also.
  4. Our home refrigerators, for that matter the ice cream freezers and the hotel kitchen deep freezers, all of these have been designed to maintain temperature of a product which is already at that temperature. They are not designed to bring down the temperature.
  5. When you try using such freezers to bring down the temperature you actually are comprehensively and totally messing things up.
  6. Now we studied in our 8th class physics that any liquid expands between 0 to -6 degrees centigrade. That is why the silicon glass water bottle will break. The water inside it will expand between when its temperature is between 0 and -6 and break the bottle in the process of creating space for itself.
  7. Meat is nothing but muscle. Muscle is made of protein, which is nothing but amino acids and they are in turn made of cells. Cells contain a liquid called as Cytoplasm. That is exactly what gives the taste to any meat. For that matter a prawn tastes like a prawn and fish tastes like a fish largely because of the muscle composition and cytoplasm.
  8. Now when fish is frozen in a hotel deep, this is what happens.
  9. To sum it up in one phrase, what is called as maximum ice crystallization happens.
  10. Because of the relatively low temperature in which it is being frozen (obviously - 18 is higher than - 40) the liquid inside the meat takes its own sweet time to get frozen and in this process starts forming into large ice crystals (Why can you find large air bubble kind of bubbles when you make ice at your home and how come the same is not found in the big commercial ice blocks, have you ever thought about it?). When the temperature reaches 0 and going down, the cytoplasm in the cells starts expanding and since it has all the time in the world to form large ice crystals owing to relatively low temperature, at one point of time it will break open the cell wall (just like that water in the silicon glass water bottle) and drip out, making the meat loose its quality and texture and ultimately the taste.
  11. Finally, this process ends after the temperature drops below -6 and ultimately the fillet is frozen.
  12. Now when you thaw this fillet, and especially if you directly put it in water, since the cell wall is already damaged, whatever remaining cytoplasm which by now has come to the room temperature also drips, making the meat even further insipid.
  13. Further more, this process neither stops the chemical reactions (temperature need not necessarily be -18, a lot of deeps operate at -16 also and for the chemical reaction to stop it has to be less than -18 degrees centigrade) nor does it stop the enzymatic reactions causing deterioration of the meat quality (-38 degrees and less) So, literally you really do not know the quality of what you are eating. Best of the hotels in this country do this.
  14. Now look at what happens if you use blast freezing or IQF techniques.
  15. As the temperature is relatively very low, -40 degrees and below, minimum ice crystallization happens, in other words quick freezing happens.
  16. The process of forming smaller ice crystals is so quick that although cytoplasm expands between 0 and -6 degrees temperatures, that phase passes off so quickly that the cell wall does not get ruptured and hence the cytoplasm remains intact, retaining the quality and taste of the meat.
  17. When you thaw and even if you thaw it in water or even worse hot water, the dripping is comparatively very low as the meat and its cell structure remain intact. And if you thaw it the way we recommend, which is air thawing, it is even better. Finally, there is no comparison in taste, the blast frozen meat tastes far superior as against the chilled and stored one.
This is another very important reason why frozen is fresh than the so called chilled.

Now, Chef Sachin Joshi, Executive Chef of Taj Deccan, Hyderabad, a good friend of mine, did not agree with the above theory of mine. We decided to blind test. I gave him a fillet of mine of the same species of fish which was blast frozen and stored in his deep for 3 days and another chilled fillet which was stored in his deep for 3 days. He handed both of these to his sous chef and we waited in the restaurant when the sous chef brought two plates of the same item made from these two different fillets. The chef, myself , the F&B Manager all of us ate the food from both the plates and unanimously every one voted that the one made with the blast frozen fillet tasted better (We did not know which one was made from what)

I keep suggesting this test to a lot of chefs who debate on this point. What is better than self experiencing!