One of the most important functions of eggs is to provide structure and determine texture. We saw this with breads, cakes, cookies, and muffins, with brownies, and also with meringue. But there’s one more category of baked good that depends on eggs: custards and creams. Eggs set and thicken crème brûlée, quiche, cheesecake, pastry cream, and crème anglaise. In this post, we’ll first review how an egg cooks, then explore how different ingredients and techniques affect this process to create smooth custards and creams.
Now that we’ve discussed what eggs do in our baked goods, let’s see them in action! For this experiment, I baked two batches of brownies that were exactly the same, except one batch had less egg than the other.
These buns are a twist on the classic Chinese egg custard buns (奶黃包, nǎihuángbāo). They still have the creamy custard and the fluffy steamed bun, but I added pumpkin and fall spices to both the filling and the dough to create a pumpkin spice version. Notes on ingredient substitutions and the science behind the custard filling, dough, and steaming process follow the recipe!
One of the defining features of a bagel is its chewy, shiny skin, which forms when the bagel is briefly boiled before it’s baked. In this post, we’re taking a closer look at the poaching step, its effect on the bagel’s crust, and how it gives a bagel its characteristic appearance and texture.
In the recent post about starch in flour, we discussed the effect of water temperature on doughs. In Chinese cooking, different ratios of hot and cold water are combined with flour to make dough for everything from noodles to chive pockets to dumplings, all of which differ in both texture and cooking method. To explore how water temperature adds so much versatility to dough, we made dumpling wrappers using a cold water dough and a hot water dough. We then boiled or steamed both types of dumplings and compared their textures.
Castella cake is a light, fluffy cake popular in East Asia, and there are two main methods to make it. Today, we’re taking a closer look at the Taiwanese version (古早味蛋糕, gǔzǎowèi dàngāo). A typical recipe starts with cake flour and cornstarch in hot oil, then adds milk, egg yolks, and an egg white meringue. In this post, we’ll focus on the ingredient that’s less common in cakes: the hot oil. We’ll bake two cakes, one with hot oil and one with oil at room temperature, and we’ll discuss the effects of the hot oil on the flour and cornstarch, the batter, and the final baked cake.
Tangzhong (from the Chinese 湯種, tāngzhǒng) is a breadmaking method derived from the Japanese breadmaking method yukone or yudane. It’s recently gained popularity largely thanks to the Chinese cookbook 65°C Tangzhong Bread by Yvonne Chen. For the tangzhong method, a small portion of the flour and water are cooked together to 65°C (149°F), then added to the rest of the bread ingredients. Tangzhong is known to keep breads softer and moister for longer due to the gelatinized starch in the cooked flour. To taste the effects of tangzhong for ourselves, we made two sets of bread rolls with the same ingredients. Half the rolls were made with tangzhong, and half the rolls were made without.
Bread dough doesn’t have to be baked. In Chinese cooking, for example, it’s often steamed to make buns. Commercial western-style bakeries also use steam to bake larger loaves with shinier, crisper crusts, an effect home cooks replicate with Dutch ovens. In this post, we’ll compare three methods of cooking bread dough using 花卷 (huājuǎn, literally “flower roll”), a type of Chinese steamed bun speckled with scallions. We’ll compare the traditional steaming method to baking and to baking with steam.
In the last post, we discussed the molecular details of starch: what it is, where it comes from, and how it changes with water and heat. Today, we’ll apply those concepts to baked goods with a focus on the starch in wheat flour. Although flour is often noted for its gluten, it actually contains 68–75% starch. So when we consider the chemistry of any baked good that contains flour, be it cake, bread, or cookies, starch always plays a role. And in foods cooked in steam or boiling water, starch helps create textures as diverse as soft skins on steamed buns, chewy crusts on bagels, and crisp shells of choux pastry.
As bakers, when we think of starch, we often think of its function as a thickener in custards and sauces. Although starch is indispensable for pie fillings and pastry cream, it also plays a role in the pie crust and choux that hold them. Starch is as important as gluten for structure and texture in baked goods. It feeds yeast and interacts with proteins, sugar, and fats. We use it to form thin, crisp crusts on bread, chewy crusts on bagels, and tall shells of choux pastry. So let’s dive into the science of starch, starting with a description of what it is and an understanding of how it interacts with heat and water.