Fish Defrost Tunnel

[gwapa]

Normally we frost thing. Now a Fish plant canned ask me to short the time to defrost 20 metric ton of fish per day.

Do anyone has some tips to do that?
I am thinking in a defrost tunnel

Thanks for your tips
Regards
Gwapa

[chemi-cool]

Never heard of defrost tunnel but I have built a unit that uses liquid ice for killing fish and cooling them before cleaning and packing so warm water would come to my mind as a defrost agent.
More then that, you can use the heat rejected from the condensers to heat the water for defrost.

[Sandro Baptista]

Yes defrost tunnel it's a possibility. I have done one some day with heat glycol recovery from the refrigerant plant. The air around the +10ºC with the fans always on and when the air temperature drop the heat was on.
The product was a kind of squid, I don't know how to tell in english (pt » "choco").

You can also use a water tank with shaked water by a propeler mantained by an heat exchanger recovered from an refrigerant plant, as chemi-cool just say, or with a fire burner.

[Magoo]

At 20 tonnes a day you will need a spiral heating system, for the retention and thawing time. Depending on the out feed temp required. Similar to what is required to freeze product, but in reverse. alternative is a tunnel 600 plus metres long. Is the product in blocks or free flowed frozen IQF.

[gwapa]

The fish is just tuna meat. It is imported and came wraped and boxed. The tuna come in pallet more or les 1,8 m hight
and is store in a freezer at -28ºC.
They require the tune at +10ºC to be ready to can those.
The point is that the factory wants to improve the time of defrost without niether drier the fish nor overheated
I thought in a bacht tunnel . Do you have any tip to disight it?
thanks
Gwapa

[Magoo]

Try researching microwave tunnel heater thawing, similar used for thawing frozen meat blocks

[Josip]

Hi, gwapa

The fish is just tuna meat. It is imported and came wraped and boxed. The tuna come in pallet more or les 1,8 m hight
and is store in a freezer at -28ºC.
They require the tune at +10ºC to be ready to can those.
The point is that the factory wants to improve the time of defrost without niether drier the fish nor overheated
I thought in a bacht tunnel . Do you have any tip to disight it?
thanks
Gwapa

I'm not sure about defrosting fish in water (possible cross-contamination of complete batch with some bacteria), by this way it will be added a lot of water into fish meat ... they like to can fish meat and oil but not water

... then restrictions or rules for food processing by GMP-Good Manufacturing Procedures, then HACCP and ISO too ....

In a batch tunnel you will overheat meat outside to reach +10ºC in the middle ... it will be reverse of freezing where we attack fresh meat with air temp of -40ºC and after 24 hours we hardly reach -18ºC in the middle if the meat piece is bigger ... what will happen in reverse process ...

I think that Magoo's suggestion is much better, of course packages must be unpacked and frozen blocks separated on thawing plates or similar .... heating is more evenly with microwave heaters ...

must say have no experience with this kind of defrosting ... and that is reason to put more questions then answers


Best regards, Josip