Keeping fried foods crispy

How to Keep Deep Fried Foods Crispy

What’s the problem?

I always wonder why some fried foods get soggy or soft as short as 30 minutes after cooking. Even when properly fried, some fried foods do not keep while others stay crispy for a long period. A classic example are fast food fries: they all pretty much go soggy after 20 minutes.

Why is this even a problem? Just eat faster

Sometimes there are fried foods that you wish to serve at room temperature. Vietnamese bánh cam are not usually served fresh and hot out of the fryer. If we can keep it crispy long after frying, that would be the dream.

Potato chips are another example of deep fried foods that we don’t necessarily eat hot out of the fryer.

Moisture, the root cause of our woes

I read this SeriousEats article and it explained the nuances involved when deep-frying. Assuming the food was properly cooked, it will come out of the fryer crispy. If it gets soggy after this point, the issue is excess moisture. This is why “it’s done when it floats” is a common check for doneness. The moisture boils off and leaves air pockets, lowering the density of the batter.

How do we do this then?

The recipe of the batter is really important. You want a viscous batter that will cling well and thick. But not too thick, less you end up with too much batter and are not able to boil off moisture before it overcooks. One trick you can use is to use alcohols, which evaporates more readily. This is one reason why many recipes call for beer batters.

Alcohol will also inhibit gluten-formation, which will lend to a more crisp batter. It won’t trap moisture and will give way the vaporization of water/alcohol during frying.

When done frying, be sure to keep cooked foods on a rack so that water moisture can continue to boil out. Be sure to place on a paper towel to absorb excess oil, so that it does absorb back in.