1500gpure sweet potatoes , skin already removed and completely cleaned
wateras needed, I use around 7L
Instructions
Remove the skin carefully and make sure no skin pumps attached, then cut into smaller pieces. Transfer to a blender, add water to cover the sweet potatoes. Blend until really smooth by batches.
Strain the content to separate residue and the starch liquid. Wash the residue and strain to separate as more starch as possible.
Set aside until the starch is settled (I recommend at least 4 hours resting).Remove the water gently above. Add around 1L water, mix well, repeat the straining and settling process (make sure no sand and other impurities contained).
Set the liquid overnight (Note 1) (long resting time helps to remove the water content in the starch block) and pour off the water above. Here we get the pure sweet potatoes starch. Spread on a tray and dry under sun or bake in oven at 50 degree C until well dried.
If you want to store the sweet potato starch, drying is extremely important. Well dried sweet potato starch can be easily smashed into powder.
Video
Notes
If you find the water above is not clear enough during the last settling (may be slightly colored), after most of the starch is settled, you can gently pour off the water and then reload with clean water. No need to stir. After changing the water once or twice, the water should be clean and clear.