On food and cooking the science and lore of the kitchen ( PDFDrive ) 1286

ofsugarandwateruntilitboils,andthenkeep
itattheboilandwatchitstemperature.At
235ºF/113ºC,orabout85%sugar,thecook
canstoptheconcentrationprocessandmake
fudge;at270ºF/132ºC,or90%,taffy;at
300ºF/149ºCandabove,nearing100%sugar,
brittlesandhardcandies.
The Cold-Water Test Although it was
invented 400 years ago by Sanctorius, the
thermometer has been a common household
appliance for only a few decades. Beginning
inthe16thcenturyandcontinuingtothisday,
confectioners have used a more direct means
of sampling the syrup’s fitness for different
candies: they scoop out a small amount, cool
it quickly, and note its behavior. Thin syrups
will simply form a thread in the air.
Somewhat more concentrated syrups form a
ball when dropped into cold water, and the
ball will be soft and malleable between the
fingers; as the concentration increases, the


cooled ball becomes harder. The most
concentratedsyrupsmakeacrackingsoundas
they turn into hard, brittle threads. Each of
thesestagesindicatesaparticulartemperature
range and suitability for a particular kind of
candy(seeboxbelow).
SyrupBoilingPointsDependonSugar
Concentration

The boiling point of a sugar solution
increases as the concentration of sugar
increases. This graph shows the
relationship between boiling point and
sugarconcentrationatsealevel.

TheHeatingRateAcceleratesDuring
CookingAswecookasugarsyrup,mostof