We plant 2 varieties of tapioca or cassava (ubi kayu) at the farm: Ubi kayu pulut and Ubi kayu merah. This articles focusses on ubi kayu pulut. I have heard stories of how this particular variety was planted during the Japanese occupation of the then Malaya and was the replacement for rice as all the rice was confiscated by the Japanese for their consumption. This particular variety is soft and melts in your mouth. It doesn't take long to cook it and cooks in less then 15 minutes when steamed and I find that it is best steamed as it has that fluffy texture. Sometimes when we harvest I get tubers that are big wishing at 5-6 kg thus not popular among our customers as it is too big. Some are scared to buy it thinking that it is probably hard like the root. So we often end up with consuming it ourselves and since it is so big, we also share with the chickens and dogs.
Now I have found a solution for these big tubers as well as excess tubers: to turn them into tapioca starch and flour. After researching and experimenting, I found that it is not difficult to make them. I choose this variety because you end up with pristine white starch and flour - no bleaching, refining, etc. needs to be done to make it white. It would be a shame to contaminate organically grown tubers with chemicals to produce starch and flour. What I end-up with is organic, gluten-free starch and flour that can be used in many ways. Growing up, I remember my grandmother, great-grandmother and mother producing traditional dishes with tapioca both savoury and sweet. In doing my research, I find it interesting in how it has been maligned as a prohibited food for diabetics in favour of the other Big Business commercial crops but it turns out that studies done in people with a high content of their diet being tapioca has negligible to low occurrence of diabetes. It is now classified as a low glycemic index food.
First, you rinse off all the soil from the outer skin. The tubers are coated with 2 levels of skin: (1) the brown grainy texture layer that you see and (2) the pink on the outside and white on the inside layer. Both layers need to be removed to reveal the white-fleshed tuber. I cut them into big chunks so that I can handle them easier when I grate them. I just use a hand grater and grate them using the same size that I use for parmesan cheese. Being a "soft" tuber, it is easy to grate them as they slide easily over the grater.
Once you have the grated tapioca in a bowl - you can use plastic, metal or
glass bowls - I will add enough water to cover the grated tapioca. Be sure you use a large enough bowl to allow room for swishing the tapioca in the water without spilling. I let it sit in water for about 10 minutes and then I swish the mixture or using a spoon stir them rapidly for a couple of minutes. You will find that the water has turned chalky white. Place the mixture in a cloth strainer and strain the liquid. Be sure to squeeze the mixture well to get as much of the liquid out of it. I tend to use a piece of muslin cloth which I will wring to squeeze all the liquid out of the mixture.
The end result is a chalky liquid and grainy, semi-dry lumpy solids solids. The chalky liquid will produce the tapioca starch or in Malay tepung kanji ubi kayu and the grainy solid will produce the tapioca flour or cassava flour or in Malay, tepung ubi kayu. Place the grainy solids in a cool, dry area overnight covered with a cloth to prevent unwanted "visitors" or contaminants from entering.
Leave the chalky liquid in a container for a couple of hours and you will see that it has separated into two: a yellowish liquid on top and a white sludge at the bottom. Pour away the liquid and retain the sludge which is actually the tapioca starch. Let the starch dry overnight by leaving it in the container in a cool, dry area covered with a cloth. The next day, you will find that whatever liquid was left in the starch will be at the top - remove this and you will find that the starch has hardened. It is now ready for use.
You can break it up by raking with a fork and place in a container for storage. I tend to keep it in the refrigerator as it does not have any preservative or additives. I am not sure how long it lasts as I tend to use it all up within a short period of time. The starch produced is a great binding agent so I use it when I make fish balls, prawn balls, squid cakes and meatballs and I do not have to worry when I serve it that anyone with allergies to gluten or nuts or grains cannot eat them. Another great use for it is as a thickening agent to thicken sauces and gravy. Unlike corn starch which is most probably made from GMO-corn, I do not have to worry about chemical contaminants using tapioca starch.
Using ubi kayu pulut, the solids that you obtained after straining is almost ready-to-use flour. You can just run it through a grinder or food processor and you will get a fine flour. For most of our local sweet dishes, you do not have to further process it. As this variety is not fibrous, it really works well when just using it as is to make bingka ubi kayu (tapioca pie), lepat ubi kayu, and many other dishes. For people who have to be on gluten-free, nut-free or grain-free diets due to health and/or allergy reasons, this flour and the starch flour is the flour of choice as it contains no gluten, not from grain nor it it from nuts or seeds. It is also for people on autoimmune protocol diet. The flour is high in carbohydrates, good dietary fiber and vitamin C, low in fat, sugar and micronutrients so is a good replacement flour for people who are diabetic and with high blood pressure.
Another of our locally-grown plant that serves as food in multiple ways which is easy to grow and can be added to you ground-based garden (it doesn't do so well in pots).