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Sure, you can make bread with just four ingredients: flour, water, yeast, and salt. But, add a few more, and even more opportunities open up. Softer, sweeter, more tender breads start to become possible as well, by simply adding a few more ingredients: butter, eggs, milk, and sugar.
These ingredients turn your bread into an enriched bread, which which by itself is a whole world. Understanding how fats help extend shelf life, how eggs emulsify and how sugar does more than just feeding yeast opens the door to many new bread experiments. What about brioche (see below), babka or challah?
- Enriched breads contain fat
- Types of fat to use in enriched breads
- Eggs emulsify
- Milk adds water and more
- Sugar is yeast's food
Enriched breads contain fat
Definitions vary slightly, but, generally speaking, what sets enriched breads apart from their lean counterparts is the presence of (large amounts of) fat. Eggs, milk, oil, butter. They all add fat. Even though some enriched breads don’t contain fat (but do contain a lot of sugar) we’ll first focus on the role of at since it has a big impact on how bread turn out.
Fat inhibits gluten formation
To make a light and fluffy bread, you need to develop a gluten network. This network is created by kneading flour with water, allowing the proteins in flour to align and reorganize themselves. The network is great at holding onto gas bubbles and is flexible enough to expand during proofing.
Proteins need to absorb water and interact with each other to form this network. Fat can interfere with this process by blocking access to water and other proteins. This is why many bread recipes that use extensive amounts of fat call for adding the fat at the end, once the gluten network has had a chance to form. It isn’t just bad news though. This limited gluten network has its advantages as well. It makes it easier to shape enriched dough into an intricate pattern.
Fat makes a softer bread
Whereas lean breads, such as a baguette, are well known for their crusty dry crust, the opposite is true for enriched breads. Most enriched breads don’t even have a sturdy crust, and definitely not a crunchy one. Again, we have fat to thank.
Since fats, especially fats like butter, literally melt in your mouth, your bread may also taste and feel more moist as a whole.
Fat slows down staling
Enriched breads tend to stale less quickly than breads that don’t contain any fat. In order for bread to turn stale moisture needs to be able to move around and leave the starch systems. Fat slows down this process. Once cooled down after baking, the fat simply surrounds the starch, serving as a protective layer. As a result, it slows down starch retrogradation which is responsible for turning bread stale.
At the same time, fat lubricates the dough. It will help the flour particles move alongside each other more smoothly. That makes doughs with a lot of fat very flexible and stretchy. The fatty lubrication helps the expansion of the dough during proofing, but also once it enters the oven and the fats start to melt and turn liquid.
During baking, solid fats such as butter will melt and spread throughout the bread, leaving behind small pockets. This adds to the fine crumb structure of enriched breads. You may have noticed that this structure is more similar to that of cakes. Cakes also contain a large amount of fat, resulting in a similar structure. Also, there definitely is some overlap within the cake and enriched bread categories.
Types of fat to use in enriched breads
There are a lot of different types of fat that can be used in bread. You can use a liquid fat such as olive or sunflower oil, or solid fats such as butter, margarine, or lard. The distinction between liquid and solid fats is an important one. Keep in mind that liquid fats will remain liquid, even when bread has cooled down again. Solid fats on the other hand will resolidify upon cooling. As such, solid fats can help create a firmer bread.
Not every fat is 100% fat
Butter is very commonly used in bread for a variety of reasons. It adds flavor, but also makes for a nice eating experience since the butter literally melts in your mouth. But keep in mind that butter isn’t made up of just fats. It contains only 80% fat and about 20% water. As such, adding butter also adds extra moisture to your dough. If you want to replace butter with another fat, you’ll have to correct for this. The same applies for margarine.
Breads with a high fat content often contain eggs. Eggs help to emulsify the dough. That is, it helps the fat and water to remain mix and not separate again either before or after the baking process. Eggs get this emulsifying property from the lecithin molecules naturally present in the egg yolk. Lecithin can hold onto both water and fat, keeping them together.
Aside from their emulsifying properties eggs are also sources of both water and fat. About two thirds of an egg is made up of water, 20% is fat and most of the remainder is made up of proteins. The proteins fullfill an additional role. During baking they set – just like an egg does when fried – providing extra structure and stability to a bread.
Also, the proteins in eggs contribute to browning of the bread. The proteins participate in the Maillard reaction, which is responsible for browning. Some recipes will call for an egg wash on top of a bread. This again helps the bread to develop color, but it will also make the bread just ever so shiny.
Milk adds water and more
Milk, whether it’s from a cow or a plant, is mostly made up of water. As such, it is an important factor in hydrating the dough and achieving the desired consistency and stickiness. However, milk contains more ingredients the ratios of which depend on the type of milk you’re using. In cow’s milk, you’ll find about 5% sugar (lactose) as well as fat and proteins. For other kinds of milk, it will be worthwhile to check the packaging to see what other components it contains to understand its possible impact on the bread.
Sugar is yeast’s food
Your regular granulated white or brown sugar is just one of several types of sugar you can use in bread. That sugar is made up of a molecule called sucrose. Other examples of sugars are fructose (common in fruits), lactose (present in cow’s milk), glucose, or maltose. Aside from small differences in sweetness, the functionality of these sugars in bread is quite similar. Also keep in mind that sugar syrups such as honey, agave syrup, corn syrup, and maple syrup are made up of these sugars, be it in slightly different ratios.
Sugars are crucial for yeast to thrive and proof your bread. However, you don’t necessarily need to add sugars to do so. Flours will contain enough sugars during resting to provide food. Adding a little extra can help speed up the proofing process.
But more is not necessarily better
Even though yeast needs sugar to survive and thrive, it can only handle so much. When there’s too much sugar, that sugar pulls on the moisture in the dough, making it harder for the yeast to access enough water. As such, breads with a lot of sugar will actually proof more slowly than those with no sugar at all. In some cases, you might even need special osmotolerant yeast that do enjoy these high amounts of sugar. Yeast really only need a little bit of sugar to do their thing, so adding large amounts of sugar will almost always leave some sugars behind.
Sugars hold onto water
Sugars love moisture. They’ll quickly dissolve in water and will hold onto that water. As such, they’ll interfer with the hydration of flour. But, by holding onto water they can also help ensure a crust remains soft and it can keep bread moist for longer, protecting it from drying out.
Sugar browns bread
For bread to turn brown you need both proteins and sugars. Again, flour can supply the necessary sugars. But, adding some extra sugars speeds up browning considerably! Enriched breads with a decent supply of sugar are even prone to burning in the oven and often need to be baked at a slightly lower temperature than ‘regular’ breads.
Sugars sweetens breads
Of course, any remaining sugars in the bread after baking will impact the taste and sweetness of a bread, as you’ll notice in the recipe for a brioche bread below. Give this enriched bread a try and then start experimenting with your own ratios!
Gan, Z. & Angold, Roger & Williams, M.R. & Ellis, Peter & Vaughan, J.G. & Galliard, T.. (1990). The microstructure and gas retention of bread dough. Journal of Cereal Science. 12. 15-24. 10.1016/S0733-5210(09)80153-7, link
Pareyt, Bram & Finnie, S. & Putseys, Joke & Delcour, Jan. (2011). Lipids in Bread Making: Sources, Interactions, and Impact on Bread Quality. Journal of Cereal Science. 54. 266. 10.1016/j.jcs.2011.08.011, link
Nathan Myrvold, Francisco Migoya, Modernist Bread, volumes 2 and 4, The cooking lab, 2017
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