In Japanese cuisine, we often use “Katakuri-ko” (“Ko” means “powder”), while corn starch is more common in Canada. Katakuri powder is made from potatoes and cornstarch is made from corn. Both are quite similar and can mostly be replaced by each other, but the texture and effects are slightly different because the raw materials are different.
In this article, I want to explain what exactly Katakuri powder is, what we use them for, and what is the difference between potato starch and cornstarch.
What is Katakuri Ko (Katakuri Powder)?
Originally, Katakuri powder used to be made from the rhizome of Erythronium japonicum (Asian fawn lily), a plant of the lily family. However, it is now made by extracting starch from potatoes because of the lack of raw materials. So, we can say that it is a type of potato starch.
We often use Katakuri powder in Japanese cuisine. It may not always be available in Asian supermarkets, but you can buy potato starch instead.
What do we use Katakuri powder, potato starch or cornstarch for?
The effects of Potato starch including Katakuri powder and cornstarch are similar. We use them to give thickness to the sauce or to give a crispy texture to deep-fried food.
In Japanese cuisine, we often use Katakuri powder when we deep-fry meat or fish. Using potato starch or cornstarch can give a lighter and crisper taste than using wheat flour.
In Chinese cuisine, particularly in Cantonese cuisine, they often use potato starch in order to give the thickness to a sauce or soup. They add the starch water to the food at the end of stir-frying to give it a thick and smooth texture. We also use Katakuri powder in Japanese cuisine aiming to give a thickness to the sauce.
Besides that, we sometimes sprinkle potato starch on the meat before stir-frying. It’s because coating the meat with potato starch can prevent the juice from coming out of the meat, so that you can keep the meat moist and tender. Another reason is that the powder on the meat surface absorbs the sauce, which allows you to use less seasoning including salt. You can make delicious food even if you reduce the amount of salt or sugar. At this point, you can use wheat flour to have a similar effect, but the wheat flour can give the meat a crispy taste while potato starch (or cornstarch) can give a springy and moist texture.
You can get a better effect from Katakuri power or potato starch when you use them to warm food, while cornstarch is suitable for chilled food such as pudding, custard cream, or cold dessert. It’s because the two of them work differently at different temperatures.
Can we replace potato starch and cornstarch when cooking?
Katakuri powder (potato starch) and cornstarch are both fine white powders. Most of the time we can replace them with each other, but they work slightly differently, so sometimes you may prefer to use either potato starch or cornstarch for specific recipes. Depending on the dish, the finish and texture may differ by substituting one for another.
What is the difference between Potato Starch and Cornstarch?
So how are they different? There are some differences between potato starch and cornstarch.
Difference of Effective Temperature
As I said before, potato starch works better with a higher temperature, while cornstarch works better at a lower temperature. Cornstarch is often used for desserts such as pudding or custard cream because the constarch works well when you need to cool down the food. If you use potato starch instead of cornstarch when you make a pudding, your pudding won’t be very firm because potato starch doesn’t work well when it gets chilled.
On the contrary, if you use cornstarch as substitute for potato starch when you cook hot food such as Catonese stir-fried dishes, you need to add more cornstarch than the amount on the recipe because cornstarch doesn’t work as well as potato starch at a high temperature.
Difference of Colour
Both of them are fine white powders, but they have different colours when they are cooked. Potato starch becomes transparent after it’s heated, while cornstarch gets cloudy. So if you want to preserve the original colour of the other ingredients, you will get better results when you use potato starch.
Difference of Texture
Both of them look very fine, but precisely speaking, cornstarch is finer than potato starch. If you prefer a lighter and crisper taste when you deep-fry food, it’s better to use cornstarch. Or, a mix of both will work as well.