Health

Mmmm . . . Doughnut Perfection

By Fenella SaundersNov 1, 2000 12:00 AM

Newsletter

Sign up for our email newsletter for the latest science news
 

What makes the Homer Simpsons of the world slaver for a doughnut? The key lies in the frying oil, says chemist Gerald DeMenna of Chem-Chek, a consulting company in New Jersey. After 50 to 75 hours of frying, heat and steam make parts of cooking-oil molecules break off into free fatty acids. The acids combine with the minerals and salts in dough to form alkalines— soap, in other words— that allow the hot oil to permeate a thin outer layer of dough. That layer quickly cooks into a crispy crust that seals the interior so that it steam-cooks and remains moist. New oil lacks the crucial breakdown products, so it leaves doughnuts pasty white and dry. "But in an abused oil, there's so much soap that the doughnut gets saturated with oil," DeMenna says. To get things just right, doughnut makers can seed new oil with samples taken from aged batches, or purchase broken-in oil previously used to fry foods such as potato chips.

1 free article left
Want More? Get unlimited access for as low as $1.99/month
Already a subscriber? Log In or Register
1 free articleSubscribe
Want unlimited access?

Subscribe today and save 70%

Subscribe

Already a subscriber? Log In or Register
More From Discover
Recommendations From Our Store
Shop Now
Stay Curious
Join
Our List

Sign up for our weekly science updates.

 
Subscribe
To The Magazine

Save up to 70% off the cover price when you subscribe to Discover magazine.

Copyright © 2021 Kalmbach Media Co.