One of the most identified traditions of Chanukah is the fried potato latkes. Recipes have been passed down for generations, detailing the specific steps needed to make the best version of the dish. Despite this, all the facets that contribute to a high quality latke can be attributed to science: the crispiness of the outside, the softness of the inside, and the overall taste. By applying food science and chemistry in the kitchen, one can achieve the ultimate Chanukah latkes.
The foundation for a good latke is the potatoes, which give the dish its signature crunch. Starch is one of the identifying factors that determines the success of frying vegetables. Potatoes, specifically Russet, Idaho and Yukon Gold, have extremely high amounts of starch, which makes them perfect for frying. When potatoes are soaked in lukewarm water, they are stripped of starch, and lose their defining frying quality. However, soaking them in cold water seals the cells and prevents starch from escaping. Thus, in preparing the raw potatoes, one should soak the raw and peeled potatoes in cold water.
That said, the starch level of potatoes is only one factor contributing to the crunch of the outside. The other determinant is the frying itself. Any organic matter develops a crispy edge when fried in oil due to the chemical properties of each substance. Water, because of the organization of its hydrogen and oxygen molecules, is polar, while oil is nonpolar. In chemistry, like substances mix with like substances, meaning that unlike substances do not mix. As water is polar and oil is nonpolar, they do not mix, and instead react strongly at high temperatures. Thus, when a latke, which contains water, is placed in hot oil, the surface reaction creates the delicious crispy edge. The more water content in a latke, the greater the reaction, which means a crispier shell. With this in mind, a wetter outside will add a new level of crunch. Only a few droplets will suffice though, because a stronger reaction with oil will mean a more dangerous stove.
While there is nothing wrong with a traditional latke, these tips based in science will transform a soggy dish into a crunchy masterpiece. As for sufganiyot, another traditional fried Chanukah food, the same science applies. While it is not recommended to put potatoes in your fried jelly donuts, rolling the raw dough in cornstarch will achieve the same results. So this Chanukah, turn your kitchen into a laboratory, and experiment with food science.
Latke recipe: https://www.delish.com/cooking/recipe-ideas/recipes/a50756/best-latkes-recipe/