Today I planted another cacao tree and started running a batch of milk chocolate. I didn’t run the tempering machine because I forgot to prepare the silk. Cacao butter silk is pure cocoa butter held at 92.3F (35.5C) for over 12 hours and it turns into a paste full of Type 5 crystals. Yes crystals, kind of like how ice, or salt and sugar crystalizes… cacao butter behaves the same way.
Cacao butter can form 6 different types of crystal structures and this ability is called polymorphism. When chocolate is melted and hardens it will naturally form type 1, 2, 3, 4 and 5 crystals giving it a brittle consistency and a dull and whitish look aka untempered chocolate. This greatly affects the overall mouth feel and experience.
Properly tempered chocolate is first heated to melt and then cooled down to about 80F and then again heated back up to about 89.7F. At this temperature only the Type 5 crystals will survive and the other lower form crystal structures will melt away. When you add the silk in at this stage the type 5 crystals will replicate and stack themselves nicely. Traditionally this is all done using a cold marble surface but the machines make it a lot easier and consistent. Type 6 actually forms months later after the chocolate is already hard.
When you have only type 5 crystals in the chocolate mass and then you let that go solid, the chocolate will have a nice shiny glossiness to it. It will also have a nice snap when broken and the chocolate melts in your mouth smoother.
So just remember the next time you are eating chocolate, you are eating a bunch of chocolate crystals.
Originally posted on 2021-09-30, part of the daily planting journal behind Ha’a Chocolate’s food forest on Hawai’i Island.