For our final project we made zeppole accompanied by cioccolata calda (Italian hot chocolate). A zeppole is a fried Italian doughnut popular at street festivals and fairs! Cioccolata calda is a thick and decadent chocolate mixture that Italians drink, as we drink hot chocolate! We assumed that the zeppole would be light and airy on the inside with air pockets that formed! We also assumed that the exterior of the zeppole would be crispy and golden brown! We assumed the cioccolata calda would be thick, glossy, and smooth- and it was! All of these assumptions came true!
Look our for Chemistry Q’s marked by ‘!!’ throughout the post 🙂
Video form of the assumptions and final product! Password is chemiscry
2 cups of all-purpose flour
1 cup warm water
Pinch of salt
1 package rapid-rise yeast
6 cups vegetable oil
!!: Wait, what is yeast doing in this recipe??
Glad you asked! Yeast is used as the rising agent in our dough. The dough is simple: the ingredients are flour, warm water, yeast, and a pinch of salt. Yeast consume sugars to begin fermentation and allow the dough to rise. In this simple dough, enzymes in the yeast cause the starch molecules to break down into simple sugars that the yeast can consume. The yeast excrete carbon dioxide and ethanol into the dough. The addition of yeast to the dough not only allows it to rise, but it creates a network of gluten featuring large air pockets that trap the carbon dioxide the yeast produce. This creates a light, airy, and soft dough that holds up after being cooked.
- First, we mixed the flour, warm water, salt, and yeast together in a large bowl. Then we covered it and let it rest in the refrigerator for 2 hours. The dough should look like this when it’s done:
- Later, once the final lab had begun, we heated the oil to 375 degrees Fahrenheit. We use a saucepan, but a heavy pot could work as well! We then scooped up a tablespoon of dough and carefully dropped it into the hot oil. We found a greased ice cream scoop made the perfect size of zeppole and made placing them in the oil efficient.
- We put 3 zeppoles in at a time, they were about the size of a munchkin from Dunkin’ Donuts. We were careful not to overcrowd the fryer, so as to not drop the heat of the oil. We fried the doughnuts until the dough was a golden brown color. We immediately transferred the hot fritters to rain paper towels to drain off the oil. This is what the zeppoles should look like coming out of the fryer.
!!: We all love deep fried treats! How is oil cooking the dough?
- Great question! Hot oil, aka FAT, is used to quickly cook the dough. Cooking in oil allows for the dough to be quickly fried and achieve a crisp golden outer shell and maintain a soft, fluffy interior. Maillard browning creates the crunchy crisp exterior from the sugars the yeast have been breaking and consuming. The chemistry comes from submerging the dough (made with water) into the hot hydrophobic oil, allowing the water to immediately evaporate. The bubbling caused by the escaping water from the dough causes “forced convection” which cooks the food faster.
Link to the frying video! Password is z3ppo73
4. We sprinkled them with confectioners’ sugar and serve hot with out cioccolata calda dipping sauce!
Before we move on, here is the chemistry behind the zeppole, in convenient video form, but also in text form at the bottom the page!
video: password is ledzeppole
Now onto the Italian hot chocolate, aka Cioccolata Calda!:
- 1 cup whole milk, divided
- 1 cup heavy cream
- 4 tablespoons granulated sugar
- 1½ teaspoons cornstarch
- 4½ ounces semi-sweet chocolate chips
- In a small saucepan, we whisked together the milk, the cream and sugar. We set the saucepan over medium-low heat and cooked it until it starts to bubble around the edges.
- While the milk mixture was heating, we whisked together the remaining ¼ milk and the cornstarch until it was smooth. Once the milk mixture started bubbling around the edges, we added the milk and cornstarch mixture and whisked until it was heated through, this took about 1 minute.
!!: What is the point of starch in this recipe?Starch is used as a thickening agent in our Italian hot chocolate. The cornstarch interacts with the water molecules in the milk, trapping the water molecules which interact with the H+ atoms on one side of the starch chain and the O- atom on the other side of the starch chain via hydrogen bonding. With water trapped inside, a soft gel forms, creating a viscous liquid.
3. We then added the the chocolate chips and whisked it together until it was smooth and thick enough to coat the back of a spoon, and it did! This took about 5 minutes. Once it was thick, we removed it from the heat and poured it into our ramekins and served them with our zeppoles!
And this is the finished dessert all together! Doesn’t it look delicious?
And here is the conclusion video! The password is zeppolequeens
PLEASE CLICK FOR FULL RECIPE!!!!
Thank you all for a great semester!