(with sincere apologies to Douglas Adams.)
This question is asked often enough and definitely deserves a page of its own.
A practical, hands-on experience is never the same as theoretical information, but this, I hope, would be helpful for those who want to know how it's done.
First, you need un-fermented coconut sap, with a pH level of 5.9 or higher if you want to get a bit more technical. If you want to be sure and do not have a pH meter at hand, use freshly harvested sap that is less than 3 hours old.
(I will not delve into the details of how coco sap is collected but you can find that information here.)
The coconut sap contains anywhere from 12-17% sugar solids. The rest, approximately 80% of it, is just water.
Now, you need to boil off that water content and remove any scum or foam that floats. These scum are nitrogenous materials which may cause further fermentation rendering your sap useless for sugar-making unless removed. Stirring is not necessary, unless you want to build up your arms. (Though stirring will reduce boiling time by about 20%.) Just remove any and all scum that floats using a fine strainer.
Scum will start to float within 15-30 minutes of the boiling-off process. The quantity of scum will get progressively less after the first 2-3 skimmings.
Boil the sap until it reaches 14-15°C above the boiling point of water. Halfway through the process the sap would have changed it's color from translucent to golden brown, like certain dark honeys. Depending on your stove's heating power, this could take several hours. The viscosity will have changed from "thin" and water-like to syrupy, then to "thick", viscid liquid.
Remove your cooking vessel from the stove and churn for several minutes (anywhere from 5 minutes to half an hour) until it becomes stiff and seemingly ready to set. Churn some more, and it will then turn granular.
You should now have your granulated coco palm sugar. Enjoy.
PS
If it did not granulate (crystallize), you probably missed certain critical steps in the outlined procedure. Most common reason is not using un-fermented sap. A useful indicator for determining freshness is by sight and smell. New sap, 3-hour old or less is more rusty than white or cloudy. It also has a pleasing, fresh smell slightly reminiscent of pandanus.
Critical Control Points in the Coco Palm Sugaring process:
- Fresh, clean sap - you must have fresh (3 hours old or less), clean sap. It's better if there are no additives of any kind.
- Strong heat source - You want to boil-off the water as fast as possible. For small quantities, any stove will do. Your stove should provide you with a source of strong and steady heat.
- Skim off the scum / foam - these are basically nitrogenous materials and other impurities. Get rid of them as soon as they float.
- Right temperature - using a candy thermometer, the syrup should be ready to granulate at 14-15°C above the standard boiling point. The water boiling point can vary from hour-to-hour, and the altitude of your location. Higher altitudes means lower water boiling point. (Please adjust accordingly.) Experts can visually check when the syrup is ready but for us mortals, a candy thermometer, keen eyes to see the thermometer graduation marks through the thick steam (superman's x-ray vision will be helpful), and quick reflexes are necessary.
- Strong arms - necessary for churning the syrup until it granulates/crystallizes. Depending on quality of the sap, the temperature at which the sap was removed from the stove and the volume of syrup, this can take anywhere from 5-30 minutes.
- Patience - you need lots of this, with plenty more in reserves. Remember, you're going to evaporate plenty of its water content to get to the sugar solids.
