What is a recipe?
Recipe is nothing more than a ratio between ingredients that, when combined, magically turn into an incredible final product. Each ingredient has its function and today we are going to talk a little about the importance of fats. It all started because I wanted to make a post on how to replace butter. But the truth is that, without understanding the role of fats in general, it is difficult to talk about substitutions. Yes, this post is long and a little technical, but after it you will understand the “whys” of a lot that happens in the confectionery. So grab a coffee and let’s go!
What are fats?
Fats are substances that do not dissolve in water, which can be liquid or solid at room temperature. All fats are formed by small structures called fatty acids (AG). When all the carbons of a given fatty acid are attached to a hydrogen, we say that it is saturated. Saturated GAs are straight, easily stackable molecules, which makes fat more firm and solid. When at least one of the molecules in the molecule is not bound to a hydrogen, at that point it bends, which makes it difficult to stack, making the fat less compact, more liquid: established fatty acids (monosaturated when only 1 carbon does not bond to a hydrogen and polyunsaturated when at least 2 carbons are not attached). Ui! I know. He looks like an eighth grader, but this will be important for us to understand some things later.
That said, it is easy to “kick” the type of fat present in some foods: butter, coconut fat, lard are rich in saturated fats. Canola oils and olive oil, in unsaturated fats.
Let’s see some compositions:
- Butter: 68% saturated fat 28% monounsaturated fat 4% polyunsaturated fat
- Lard: 43% saturated fat 47% monounsaturated fat 10% polyunsaturated fat
- Coconut oil: 91% saturated fat 7% monounsaturated fat 2% polyunsaturated fat
- Olive oil: 15% saturated fat 75% monounsaturated fat 10% polyunsaturated fat
- Canola oil: 7% saturated fat 61% monounsaturated fat 32% polyunsaturated fat
Did you get it? Rafa Silvério, our official comic artist, made some illustrations to facilitate understanding:
What are the properties of fats?
Of all the physical and chemical properties of fats, the plasticity it’s the fusion point are the most important to be understood in the confectionery.
Plasticity refers to the pliability of fat. Think of fat as a modeling clay. Examples of plastic fats are butter, margarine, lard, vegetable fat. The oils are completely liquid and do not have this characteristic. Cocoa butter, on the other hand, is 100% solid, and also cannot be considered plastic. And how important is that? All! Only plastic fats can be beaten and incorporate air, in a process known as “creaming”. Cakes, cookies, pasta, millions of recipes use this method to acquire the desired texture.
The melting point is the temperature at which the fat in question changes from a solid to a liquid state. Olive oil, for example, has a melting point of around 5 degrees. That is, above 5 degrees it will always be liquid. Butter has a melting point of around 34 degrees. Above that, it’s melted butter! (But we know that it already starts to soften above 27 degrees). Vegetable fat has a melting point of around 45 degrees. What does that mean? Even if you are cooking in a hot kitchen, your fat will still be solid! Understanding the melting point is extremely important, as some recipes require the fat to be solid in order to obtain the desired result.
And what are the functions of fats in confectionery?
There are many. But the most important are:
- promoting softness: every recipe is a balance between structuring agents (wheat proteins, eggs and starch granules), which can make the product hard, and “softening” agents. And a soft product is easy to bite, cut, crumble.
- help in aerating and expanding products. This occurs in 3 ways:
- when pieces of solid fat in the dough melt and leave a space that expands in the cooking (think of the puff pastry, croissant etc)
- when a fat has water and air in its composition (butter, margarine), which evaporates / increases the pressure and expands
- when during the “creaming” process air is incorporated
- Flavor: even fats without a characteristic flavor add an extra complexity: think of boiled potatoes versus french fries!
Joyce Galvão, from the column “Química na Cozinha”, wrote a little about the use of fats in sweet dough. To read the post, click here.
The importance of butter
I think that in a Platonic world, where there were no problems with cholesterol, weight, food allergies, ideological or religious issues, everyone would only use butter. It’s because? Because it has characteristics that no other fat has and that make it the most incredible of all fats.
First, it is not that processed. It is even possible to make butter at home.
It is plastic and can be used for creaming. It melts at body temperature – which literally brings the feeling of “melting in the mouth”. It is a water-oil-air emulsion, helping to expand products. It has proteins and sugars, which when heated suffer such a reaction from Maillard (you know the grilled steak that forms that irresistible cone? That’s Maillard!) – that is, more aroma and a more attractive color. Apart from the taste, right, my people? Unbeatable!
I can’t use butter. And now?
Yeah. Despite all the amazing characteristics of butter, it is not always possible to use it. The most common causes for avoiding butter are:
- concern about the consumption of saturated fats: this topic is controversial in the literature. There are studies that defend with tooth and nail that consuming saturated fats is the same as signing a death certificate. Others no longer show so much difference. But while this struggle is not resolved, the current rule is that saturated fat is bad for the heart and should be consumed sparingly.
- food allergies: people who are lactose intolerant and / or allergic to cow’s milk protein should avoid dairy products.
- religious reasons: according to the rules of Jewish kashrut / kosher food, dairy products cannot be mixed with meat. So you ate meat and want a dessert? It has to be without butter!
- ideological reasons: as in veganism, where nothing of animal origin is ingested.
What’s up? Then it gets complicated. Because it is possible to use in many recipes oils / olive oil as a source of fat. But as they are 100% fat and have no water or air and are not plastic, they will result in denser, less arid products. In addition, we will need to adjust the amount of net revenue. It is also impossible to make a dough puff, because in this case I need a solid fat. What to do in these cases? Well, you either give up any recipe that needs creaming or solid fat or you resort to “handled fats” (designer fats). But that’s already a topic for a next post!