On Sunday, November 4, 2018 at 11:44:45 AM UTC-6, Sheldon wrote:
>
> Made in small quantities as you describe with constant stirring and
> adding more sap it really doesn't boil, it's called boiling off the
> water but the sap isn't boiling, all the stirring produces water vapor
> that disapates, more [cold] sap is constantly added which prevents the
> syrup from becoming thicker.
>
> In commercial operations huge vats are used and the water is removed
> pretty much the same as when makiing orange juice concentrate and
> tomato paste... minimal heat is applied, just enough to produce water
> vapor that is constantly removed via vacuum, there is no boiling...
> actually the water is removed tantamont to how dehumidifiers work, by
> condensation.... in a sugar house it's cold so the water vapor is easy
> to draw off and it drips away, about the same as reducing a sauce
> without boiling by tilting the pot lid. It's a slow process, that's
> why it takes days but only minimal heat is applied. A sugar house
> operates by depending on the great temperature difference of warmed
> sap and icy cold air.
>
>
https://www.youtube.com/watch?v=RuuQavF4IRY