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Author Topic: Why Freeze Food Quickly ?  (Read 3071 times)

Offline neilep

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Why Freeze Food Quickly ?
« on: 30/11/2004 15:03:58 »
This is a far more serious and important question than those being debated/discussed in the Superultramodern theory threads.

I like food, food is good and I buy it a lot. When I buy food to be fozen (and here's the question)...why would I want to freeze it quickly by putting the freezer into 'quick freeze' mode  ?...why can I just not let it freeze at the normal subzero level that is the the nominal setting ?...my freezer has this facility and I want to know why ?

Hoping this vital question meets with a warm reception.

'Men are the same as women...just inside out !'


 

Offline gsmollin

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Re: Why Freeze Food Quickly ?
« Reply #1 on: 30/11/2004 16:00:16 »
As the food freezes, and by that I mean the phase-transition between liquid and solid, ice crystals grow in the food. The ice crystals continue to grow as long as the food is left in this double-point phase. The ice crystals puncture cell walls in the food, and do a lot of damage to the food's texture. The food is now more susceptible to spoilage than when it was fresh, even while remaining frozen in storage, and will have lost a lot of its taste and appeal when defrosted.

The faster the food is frozen, the smaller the ice crystals are, and the better the quality of the food after defrosting.
 

Offline Simon

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Re: Why Freeze Food Quickly ?
« Reply #2 on: 30/11/2004 16:23:21 »
We freeze crystals to 100K in order to minimise crystal damage whilst collecting X-ray diffraction data. Quite a bit of thought goes into the freezing process and the cryo-protectant used. You know if you've screwed it up because you get high levels of mosaicity (disorder in the crystal) and lots of ice rings on your diffraction images. As a general rule "slow" freezing is never a good idea if you want to maintain structure, and I am sure this rule is similar regarding food!

Simon
 

Offline neilep

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Re: Why Freeze Food Quickly ?
« Reply #3 on: 30/11/2004 16:55:22 »
WOW !!..thank you both very much indeed.....seems totally logical...thanks for helping me understand....if you were my neigbours I'd bake you a pie or something. cheers.

'Men are the same as women...just inside out !'
 

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Re: Why Freeze Food Quickly ?
« Reply #3 on: 30/11/2004 16:55:22 »

 

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