Which is a better thickener flour or cornstarch?

Chef's answer
Because cornstarch is pure starch, it has twice the thickening power of flour, which is only part starch. ... To thicken sauces, cornstarch is combined with cold water first, which is called a slurry. Flour, on the other hand, is cooked with fat and made into a roux.Sep 17, 2020
Frequently asked Questions 🎓
Cornstarch Is the Secret to the Crispiest Fried Chicken So how exactly does it work? When paired with all-purpose flour, cornstarch helps prevent gluten development, which makes the flour coating crispier, and absorb moisture (from the frying and the chicken), which also means a crispier coating.3 Mar 2020
When paired with all-purpose flour, cornstarch helps prevent gluten development, which makes the flour coating crispier, and absorb moisture (from the frying and the chicken), which also means a crispier coating. If you already have a favorite fried chicken recipe, try replacing a quarter of the flour with cornstarch.3 Mar 2020
You can use cornstarch for coating the patties or chicken before frying. Add some garlic, chili powder, salt, and pepper to the starch for more flavor. Add the rinsed, dried chicken pieces, and toss well.
Cornstarch: When added to marinades, cornstarch provides a light coating to meat that protects it slightly from the intense heat of the wok. This helps prevent overcooking and toughening of the outer layers of meat.28 Oct 2019
Using cornstarch to fry foods, however, will get you the golden color and extreme crunchiness. This is because cornstarch is almost completely starch whereas flour has a lower starch content because it also has gluten. Some recipes might even use only cornstarch to ensure the food gets ultimate crisp status.
And, it's the secret ingredient for getting crispy coatings like tempura paper-thin. ... When paired with all-purpose flour, cornstarch helps prevent gluten development, which makes the flour coating crispier, and absorb moisture (from the frying and the chicken), which also means a crispier coating.Mar 3, 2020
Interestingly, cornstarch contains 25 to 28 percent amylose, which is higher than the amount in wheat or potato starch (which are 20 to 22 percent amylose), and this is why cornstarch works the best for making crispy coatings on fried foods.
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