This has taken lots of trial and error, but I've finally learned to make a soft and chewy cookie — and a soft and chewy peanut-butter cookie (which is more difficult to do). Now, understanding the science:
The soft part is simple: ... Milk fats soften baked goods.
Butter is probably the most popular milk fat for keeping a baked good from being too dry or too hard. Butter also has a good amount of water, but that water — meaning the total amount of butter — needs to be limited.
Although water is essential to baking, it helps to know just what it does. For one thing, water immediately dissolves baking soda or baking powder, and that causes air bubbles during baking. When water (hydrogen dioxide) reacts with baking soda (sodium bicarbonate) and heat, it releases carbon dioxide. And that leaves little (or large!) pockets of air in cakes and cookies. Those pockets of air give different baked goods various textures, depending on how much water and other ingredients there are.
But there has to be only a small amount of water to make a soft cookie that hardens a little on the crust. Depending on other ingredients, too much water can either bubble out of the cookie and cause the milk fats and sugars to dry out inside, or too much water can sit there and make a soggy cookie that remains like dough. So, just the right amount of moisture is needed — and not too much.
Finding the right balance gets complicated when you consider other ingredients. Ingredients that have tiny amounts of water in them may have what's called an acidic pH. (My definition of pH: A scale indicating the potential amount of hydrogen activity in water.)
When ingredients with an acidic pH get together in the heat of an oven, they, altogether, cause huge hydrogen explosions — as does the tiny amount of water in a kernel of popcorn. Ingredients with an acidic pH, explode in heat, creating pockets that get filled with hot, dry air from the oven. And that can either dry out a cookie, or give it a just-right dry crust with some moisture left inside.
To better control the little explosions of hydrogen during baking, it helps to limit both water and ingredients that have an acidic pH.
And many baking ingredients do have an acidic pH!
Some examples include
-
Pasteurized (meaning factory-heated or processed) honey
- Molasses
- Brown sugar
- Sugar-cane juice
- Coffee
- Chocolate
- Cocoa powder (other than Dutch-processed cocoa, which isn't acidic)
- Yeast
- Rye flour
- Wheat flour
- Vanilla
- Ice cream
- Milk
- Buttermilk
- Cottage cheese
- Yogurt
- Lemon juice / Citric acid
- Applesauce
- Cream of Tarter (a slightly acidic salt that's in baking powder)
- Baking powder (Only slightly acidic, baking powder is different from baking soda.)
- The water in peanuts, walnuts, pecans, and cottonseeds
This means many common baking ingredients have a pH that may make bake goods rise and lose moisture too quickly. For example, when baking powder reacts with other cookie ingredients that have an acidic pH, there's an extra-forceful hydrogen release, pushing moisture out and allowing heated air in — drying the cookie out. Again, there has to be the right amount of each ingredient, with only small amounts of ingredients that have an acidic pH.
And that's what can make peanut-butter cookies a challenge to keep soft. Peanuts have lots of healthy acids; and those fatty acids, by themselves, don't have any effect on the peanut's pH level. Instead, an acidic pH means that any water in the peanut is acidic.
The water in peanuts is only slightly acidic. But because peanuts are a main ingredient in a peanut-butter cookie, there is more of the acidic pH than in just a few peanuts.
To have a soft and chewy peanut-butter cookie, we need to find a way to make the pH less acidic. So, instead of using peanut butter, which is packed with slightly acidic peanuts, it's best to use peanuts that aren't packed into peanut butter. For example, we can put dry-roasted peanuts, or even cocktail peanuts, into a food processor — or into a blender with the amount of egg that will go into the cookie's dough [considering the water in an egg has an alkaline pH (instead of an acidic pH), and that water from the egg will help puree the peanuts in a blender,
without causing a more acidic pH.]
Other ways to reduce hydrogen reactions in baking is to figure out exactly how much flour will work together with a recipe's egg and sugar to produce the soft and chewy cookie we would like.
It's also important to dissolve at least some of the sugar that goes into a cookie, if the cookie is going to be
chewy. In other words, sugar, in form of a syrup, can help with chewiness. Molasses is a syrup that can make cookies chewy, but, because molasses has an acidic pH, we have to figure out the just right amount of molasses, the same way we figure out the just right amount of flour. And, figuring it all out just means
experimenting.
Soft
A soft cookie has the right amounts of milk fat and not too much water.
Although Grade AA U.S.-produced butter is a flavorful source of milk fat for baking, all grades of U.S.-produced butter have at least 80-percent milk fat. European butters are more fatty and may produce baked goods that are softer but more oily, depending on the baker's know how.
Finding a butter that works for you at home, however, may be more a matter of patience and experimentation. Even with a AA Grade on a package of butter, there's no guarantee a butter will be the consistency that yields softer baking. (By the way, the kinds of feed that cattle receive does affect the softness of butter, a fact chronicled as long ago as 1896, in an annual report by the Canadian agricultural department. And recent trends in agriculture have yielded harder butters, due to palm oil in cattle feed.) So, try different brands of U.S.-produced butter until you find one that not only is a softer butter, but that is flavorful for your cookies.
Besides being made with an appropriate butter, a soft cookie also has limited amounts of hydrogen (only a little hydrogen from the very small amounts of water in other ingredients). A soft cookie also has egg (just the right amount), and it has appropriate ratios of flour and sugar.
Chewy
A chewy cookie may need a sugar that is a syrup. When a sugar is a caramelized syrup, it stiffens when it goes into an oven, like the caramel in a candy bar. Molasses is okay for this, but, because it's a cookie we're trying to make (not a candy bar), we don't need to use very much molasses.
We can experiment and figure out the right amount of molasses — not too much — beginning with
recipes we've found. We also can figure out how long to leave a syrup ingredient in the oven, by understanding the longer the bake time, the more water is released from sugar, the more chewy or caramel-like the sugar.
But, because we don't want a cookie to harden like a rock, being in the oven too long, we need to keep it from overheating.
One way to keep the cookie from overheating, is to make sure there is lots of air in the cookie dough. Air
does not have anywhere near the amount of hydrogen that water has, so to fill a cookie dough with air (instead of with much water), can be a good thing.
"Air is a poor conductor of heat," explains a writer at Serious Eats, a dot-com. Because air does not draw heat the way a metal baking sheet and water do, the air "helps insulate the dough ..., slowing the rate at which the butter and sugar melt."
When the butter and sugar have been whipped together to form a soft, air-filled mixture that keeps the cookie from overheating, a longer bake time allows that mixture to melt more slowly and the cookie becomes more chewy.
But, in order for the cookie to keep the air we beat into the butter-sugar mixture, we need to start with cold butter (not traditional room-temperature butter),
Serious Eats explains.
Also, in my own experience, butter that's already whipped, can work just fine — never mind that some store-bought pre-whipped butters are whipped with nitrogen instead of simple air, and never mind that you would need to buy two 8-ounce containers of pre-whipped butter to substitute for one box (four sticks) of solid butter (because, the pre-whipped butter is filled with air and takes up more space in a container).
Pre-whipped Butter Can Help
It's not difficult to use store-bought butter that's already whipped. And doing so, does more than save time preparing the cookie dough. The pre-whipped butter can help ensure cookies are the same each time you make them, and I think the air from that butter helps make the cookie softer.
Some people may complain that it's hard to know how to calculate how much whipped butter to use, because there's less butter in a measuring cup of air-whipped butter than in a cup of solid stick butter. If you expect to measure a cup of whipped butter with a measuring cup (cup for cup compared to solid butter), you won't have enough butter in your cookie, because air in the whipped butter takes up space in a measuring cup.
But thank goodness store-bought whipped butter is put into containers based on weight, not volume or cups. That said, it helps to know a four-stick box of solid butter weighs one pound, and an 8-ounce container of store-bought whipped butter weighs one-half pound. And, although air does have weight, the air in a container of butter doesn't amount to enough to measure for baking.
That means there is about half as much butter in an 8-ounce store-bought container of butter, than in a one-pound box of solid butter. So, in place of solid stick butter, just substitute twice as much store-bought whipped butter in measuring spoons or measuring cups — while the whipped butter is still cold, not melted!
Another easy way to know how much pre-whipped butter to use, is to think an 8-ounce container of it is equal to about two sticks (one cup) of solid butter. If you are only using a small amount of butter — if you would use only one stick (one-half cup) of solid butter — you would only need to use about half an 8-ounce container of store-bought whipped butter.
Easy reminders:
- Buy two, 8-ounce containers of store-bought whipped butter, to substitute for a whole four-stick box of solid butter.
- Buy one, 8-ounce container of whipped butter, to substitute for two sticks of solid butter.
- Use only half of an 8-ounce container of whipped butter, to substitute for one stick of solid butter.
- Because one stick of solid butter is one-half cup, use a measuring cup to scoop twice as much whipped butter. Scoop one cup of whipped butter, in place one-half cup solid butter.
- Scoop one-half cup of whipped butter, in place of one-fourth cup solid butter.
- Scoop two tablespoons of whipped butter, in place of one tablespoon of solid butter, and so on.
- Use twice the amount of whipped butter in place of the amount of solid butter in a recipe.
One advantage to using the pre-whipped butter is that it's not going to waterlog the dough. It may be a fair assumption that store-bought whipped butters have less water, based on how they are factory whipped.
If using store-bought whipped butter, instead of whipping stick butter at home, don't overmix the store-bought whipped butter into your sugar — don't beat your store-bought whipped butter together with your sugar for very long at all. And, remember to keep the butter cold so that it can hold its cold air and stay in the oven a little longer.
In the end, the sugar molasses and butter that stay in the oven a little longer, are going to do two things: they will harden the crust of the cookie, helping keep the inside from completely drying out; and, through caramelizing, they will add chewiness to the butter's softness.
The Small Print
Molasses does better than dry brown sugar, because dry brown sugar chemically binds with most of the water in the cookie so that the cookie becomes too damp or waterlogged to form a crust. The amount of time a waterlogged cookie dough will need to be in the oven in order to dry out, can only make a dry cookie. Again, the water prevents a crust, and without a crust, the cookie loses so much moisture, it may harden "like brick."
But the molasses isn't going to bind to very much water in the cookie. Instead, loose water in the cookie will bind with the flour; and the molasses mostly will be free to harden on the outside of the cookie and to become chewy inside the cookie.
Although molasses, by definition, is sugar that is already
caramelized, it becomes more caramelized (to the point of being chewy), when more of its water steams away with heat. To further caramelize molasses while baking a cookie, the temperature needs to be at least 350-degrees Fahrenheit — but 375-degrees F is probably best.
It's also important to put the cookie tray midway between the top and bottom of the oven — not too close to the hot top, and not too close to the hot bottom, so the cookies don't dry out.
As already mentioned, another element to baking a cookie that's soft and chewy, and a little crusty, is to use just the right amount of egg — not too much.
Egg is needed to hold fats and liquids together in the finished dough. But we limit the amount of egg, because too much causes baked goods to become spongy, like cake; and we want to make cookies, not cake or muffins. The science behind why eggs help make cake when combined with enough flour, is that the protein in the eggs binds with the protein in wheat; those protein strands stretch and create pockets of air that are less dense than the air pockets in a cookie. So, if we want to make cookies, we need less egg to flour than the ratio of egg to flour in a cake. For a cookie, we need just enough egg to hold the dough together.
Other Ways to Limit Water
If there's a need to reduce water so that your recipe will have a crust and won't be spongy or too dry, try to
- Refrigerate the dough for a short while, so that some of the water evaporates, and some of the water is absorbed by starches in the flour. (But avoid refrigerating too long, because the dough will get too dry and tough. And avoid refrigerating the dough altogether, if you want molasses to caramelize.);
- Use salted butter. (Salt in butter helps to more gently knock down or reduce the number of protein (gluten) strands than table salt does; so water is released more evenly than through using table salt. When air pockets form more evenly between protein strands, you're more likely to lose air in a cookie gradually instead of quickly. Quick releases of both air and water during baking, can make for a dry cookie.);
- Use a just-right amount of butter. (Both the butter and sugar encourage crust formation so that, after water is finished steaming up, there's a crust to keep the cookie's inside moist. Butter also repels some of the water that would bind to the flour, so more of the water steams away before the crust forms.)
A few sources:
craftybaking.com
bakerpedia.com
berries.com/blog/science-of-baking
https://foodcrumbles.com/why-not-all-butters-are-the-same/
Other interesting links:
https://coolconversion.com/cooking-weight-volume/#
learningcenter.nsta.org/products/symposia_seminars/ACS/webseminar5.aspx
montessorifarmhouse.com/single-post/2017/04/04/Fossil-Cookies
littlebinsforlittlehands.com/gingerbread-man-chemistry-experiment-science/
For the older young scientist:
Did you know multiple studies say artificial sweeteners may be raising type 2 diabetes risks? Scientists suspect that's because those sweeteners may be upsetting some people's gut health — not to mention the surprise finding that many folk are holding to habits of eating foods that can be hard on their health, while also using the sweeteners: https://www.unisa.edu.au/Media-Centre/Releases/2019/heres-a-bitter-pill-to-swallow-artificial-sweeteners-may-be-doing-more-harm-than-good
Did you know molasses (a sugar) was sometimes a home remedy in our early history in America? Molasses has a troubled history, but, somewhere along the line, people recognized molasses as a flavorful way to ease certain symptoms, from menstrual complaints, to constipation, mainly because of the magnesium in molasses.
Most molasses is made when sugar-cane juice is boiled until sugar
crystals form, to begin making the granulated sugar many of us know the
best. Molasses is the caramelized syrup that's left over when sugar
crystals begin to form during that process. And it's a syrup that's far from outdated.
Globally, molasses remains a standard ingredient in livestock feed today, because it's palatable to animals, it's an easy source of energy, it's fattening, and "at times appears to exert a tonic effect."
Indeed, one recent study, of humans, found a little molasses helps control blood-sugar at meals that are made up of large amounts of carbohydrates. The study says that, while molasses does not have any effect on lowering blood sugar as part of an ordinary diet, it does lower spikes in blood sugar when heavy carbs are the main food at a meal.
But, being sugar, how can that be?
The answer, in short, is that the juice from sugar cane is more than only sugar; the raw juice is loaded with sugar, but the juice also has minerals and organic compounds that can be beneficial to our health. Even after the juice is boiled down so that it becomes molasses, it has some of the sugar-cane plant's antioxidants and other organic compounds.
According to the study mentioned above, when a person eats a small amount of that beneficial mix of antioxidants and other compounds from molasses, that prevents some carbohydrates and simple sugars from ever entering the bloodstream. As a result, the pancreas doesn't need to produce large amounts of insulin in response to the high-carb meal, and the insulin the pancreas does produce is able to work more efficiently in clearing the blood of excess glucose: https://www.researchgate.net/publication/282248574_Postprandial_insulin_and_glucose_levels_are_reduced_in_healthy_subjects_when_a_standardised_breakfast_meal_is_supplemented_with_a_filtered_sugarcane_molasses_concentrate
This study may be helping bring molasses into the 21st century!
At one point in the 20th century, some homemakers may have thought of molasses a little like cod liver oil, which was used to prevent rickets. Some may have been told the iron in molasses could help prevent anemia. But folk remedies as such, are not like findings from the above research. After all, there really isn't enough iron in molasses to justify it as a home remedy. Writes Registered Dietician Kayla McDonell for the dot-com Medical News Today: "Nutritionists do not recommend that people start eating
molasses for nutrients, because its sugar content is so high. The best way
to get these nutrients is by eating whole foods."
Yet there's good use for molasses. Today's research conceivably could lead to pharmaceutical advances and give simple molasses yet one more use — beyond livestock feed, ethanol production, and homemaking. And where homemaking is concerned, never mind the home remedies. Molasses still makes a pretty mean cookie.
To that end, writes McDonell, "If you are going to eat sugar anyway, molasses is likely a more healthful alternative."
"Go and enjoy good food and sweet drink, and send some to those who have nothing prepared. ... Do not grieve, for the joy of the Lord is your strength."
Nehemiah 8:10
