[Sca-cooks] Candy question, mostly...

[ranvaig at columbus.rr.com]

>
>Can someone tell me what are the important factors that determine how thick
>it sets up? As I said, this was OK, but I'd rather have it a bit firmer at
>room temp- this was fine refrigerated, but would have been too soft at room
>temp (I say "would have been" because it sorta vanished ;-)
>
>I've done fudge before, but it was many years ago, and I'd never done it
>with cocoa before- we always used the unsweetened chocolate chunks. Any
>information on the process would be very helpful.

The Physical Chemistry of Making Fudge
http://www.gi.alaska.edu/ScienceForum/ASF8/871.html

Fudge is one of the rare exceptions to the rule 
that sugar crystals are not desirable in candy. 
Tiny microcrystals in fudge are what give it its 
firm texture.

While you ultimately want crystals to form, it's 
important that they don't form too early. The key 
to successful, nongrainy fudge is in the cooling, 
not the cooking. The recipe calls for heating the 
ingredients to the soft-ball stage, or 234° 
F, then allowing it to cool undisturbed to 
approximately 110° F. If you stir during this 
cooling phase, you increase the likelihood that 
seed crystals will form too soon.
....
When the fudge has cooled to about 110° F, you 
want to start the crystallization process. You 
start to stir, and keep stirring, until the candy 
becomes thick. The more you stir, the more 
crystal seeds you get. But instead of getting a 
few huge crystals (and grainy candy), you get 
lots and lots of tiny crystals, which make for 
thick, smooth candy.
http://www.exploratorium.edu/cooking/candy/fudge-story.html

Do not stir fudge once the boiling starts, unless 
the recipe specifically requires it; unnecessary 
stirring may cause graining. Beating fudge is 
very important. While fudge is cooling, it is 
necessary to make the fudge creamy and smooth. 
Beating must be started while fudge is 
comfortably warm and continued until it is almost 
firm. For fudges that require cooling and 
beating, beat hot fudge in pan or pour the hot 
fudge on a marble slab or formica; cool to 
lukewarm, then paddle with spatula, until of the 
right consistency to spread.
http://www.recipesource.com/desserts/candy/fudge/01/rec0119.html

Most ruined batches of fudge - the grainy ones, 
the mushy ones, the separated, oily  ones - can 
all be blamed on sugar that didn't crystallize 
just right.  But sugar  crystals can be 
controlled.  How, you ask?  The answer may seem 
ridiculously obvious,  and yet it's the real key 
to perfect fudge: FOLLOW THE DIRECTIONS!  In most 
of the  cooking you do, you can get away with 
substituting ingredients, making additions, 
skipping a step, or changing the cooking 
temperature, but with fudge, it's vital to 
follow the recipe instructions exactly.  Stir 
when the recipe tells you to stir;  don't stir 
when the recipe tells you not to stir.
http://allrecipes.com/advice/coll/christmas/articles/76P1.asp

Ranvaig