If you have made Karaage or Agedashi–tofu before, most likely you have already come across Katakuri-ko 片栗粉. Well, it is actually a kind of starch that oftenly used in Japanese dishes.
This starch was originally extracted from a wild plant called Katakuri, a kind of pink-flowered plant similar to trout lily. But due to the fact that the flower was at risk of extinction, people looked for alternatives and started to use potato starch which bares a stark similarity. However, even after the swap, the name for the starch remained unchanged and still known as Katakuri-ko 片栗粉 today.
Commonly available at the Japanese supermarkets or Asian grocery shops, you can find them under the dry ingredients section. In Japan, they are usually packed in small quantities like bags shown above and mostly made of potatoes from Hokkaido.
Above are some brands of potato starch I have been using which work really great.
This is a must-have in my pantry. So once the bag is opened, I would usually transfer the content into an airtight container to keep fresh. It is also good to store the container in a dry and cool place.
Katakuri-ko is ideal when you need something to thicken gravies, sauces, and even in custards and puddings. Japanese also use this starch as a coating for fried food instead of premix flour.
Many have this question, “What if I can’t find potato starch, is it possible to replace it with corn starch?
Well, yes that’s possible. In fact, I find corn starch the most compatible to replace potato starch compared to others. However, when mixed with water, cornstarch dissolves fast and work up to a gel-like mixture easily, while potato starch remains pourable with a consistent milk-like texture.
So when you use cornstarch as a coating for your fried food, you might see some gel-like build-up on food sometimes. For that, to have the best result, I would still advise you to stick back to potato starch.