The Chemistry of Baking

The following information is a place to converse about the Chemistry of Baking

Tentative Schedule

SOfIA 2016 Schedule

Chemistry Topics

• • SOfIA students: put this in the order that you will be presenting, and put the correct name with the topic.

Flour Types

• Brandon

King Authur Flourwebsite

specifty flours

Basic Introduction

Flour plays a vital role in the chemical process of baking. Each kind of flour has its own special characteristics, which is why it's important to know which kind of flour will best suit your desired baked good. The biggest difference between the various kinds of flour lies in their protein content. This affects how the flours absorb water, for example: the same amount of water in a cake flour could lead to runny, more watery dough while it could lead to a more structured, firm dough with bread flour. Protein content also plays a large role in the development of gluten, which is responsible for the structure, rigidity, and texture of the intended product. I will later elaborate on exactly how reaction between flour and other ingredients leads to gluten production and such drastic differences in our baked goods.

The Different Kinds of Flour

• All-purpose flour: As its name suggests, this is easily the most versatile kind of flour on the market. Its average protein content varies by brand and ranges from 10-11.7%, so it produces enough gluten to give sandwich bread decent structure without being too wholesome. Bleached flour tends to be bland and flat in flavor.

• Cake Flour: This has a lower protein content than the all-purpose flour and averages 6-8% and therefore has much less gluten than all-purpose, which accounts for its finer, delicate crumbs. Most are put through a bleaching process, which changes the starches in the flour so that it can absorb more water and fat. (1 cup of cake flour is equal to 2 tablespoons of corn starch and 7/8 cups of all-purpose flour.)

• Bread flour: Bread flour has a relatively high protein content with averages from 12-14%. This results in a very high gluten development, giving artisanal/rustic breads their characteristic strong and chewy structure. This is often far too strong sandwich bread.

• Whole-wheat flour: This is made from all 3 parts of the wheat kernel (INSERT LINK)- the endosperm, the fiber-rich bran, and the vitamin-packed germ. These make it more nutritious, flavorful, and dense. Breads baked with whole-wheat flour tend to be heavy, hearty, and sour-tasting.

• Specialty Flours: There are a few specialty flours that the average chef will not encounter in their everyday lives and tend to be more useful to the professional bakers. These include:

• Pastry Flour: This flour is often used for pastries and contains a protein content between the all-purpose flour and the cake flour.

• Self-Rising Flour: This contains a leavener for convenience.

What's the big deal about flour?

Flour is a crucial component of the reactions that occur when baking. All flours naturally contain both alpha and beta amylases, which are enzymes that break the starch (link) in the dough down to fermentable sugars. These fermentable sugars are maltose and glucose. Scientists have looked at a way to bring the quality of slowly cultured starter dough to the doughs that many people use nowadays by enriching flours with more amylase enzymes. This expediates the process by breaking the starch down in less time, which means that there are more sugars available for yeast fermentation and a quicker production of carbon dioxide gas and ethanol, which gives dough its characteristic scent. As previously mentioned, protein content is responsible for each kind of flour's unique attributes. The two proteins that are important to gluten production are glutenin and gliadin. These proteins are hydrated when the flour is mixed with water, resulting in gluten formation. This is because these proteins are dominated by hydrophobic amino acids like glutamine, which has a strong tendency to form hydrogen bonds between protein strands. These hydrogen bonds are solely responsible for the structure and behavior of gluten. We see it as well-structure bread crumb from an artisanal loaf that you can get at a specialty bakery or the less-structured crumb of a cake or cupcake.

Water

Does water ion concentration have an effect of the baked good?

Sugar

• Rachel
  • Lactose: a sugar prsent in milk, a disaccharide contain flucose and galactose units
  • Maltose: a sugar produced by the breakdown of starch by enzymes found in malt and saliva, a disaccharide consisting of two linked glucose units
  • Sucrose: a compound that is the chief component of cane or beet sugar

Protein

What is a protein?

• The Oxford Dictionary's definition of a protein is "any of a class of nitrogenous organic compounds that consist of large molecules composed of one or more long chains of amino acids (also known as a polypeptide) and are an essential part of all living organisms.
• They are essential to help assist in muscle, hair and collagen growth. They also work as enzymes and antibodies.

What are good dietary sources for proteins?

• Seafood
• White meat
• Dairy products (milk, cheese, yogurt, etc.)
• Eggs
• Beans

Sources

• http://www.oxforddictionaries.com/definition/english/protein
• http://www.webmd.com/fitness-exercise/guide/good-protein-sources

Starch

• Tatyanna

Yeast-Rising to the Occasion

Yeast is an essential part of most baking processes. By breaking down the sugars provided by the mixture of flour and water, yeast begins to consume the sugar within the mixture, producing carbon dioxide (CO2) and alcohol in the process. When fresh bread dough is left proof, the CO2 gases build up within the dough, causing it to rise when left alone. However, a great deal of things are happening within the dough while proofing......

Along with aiding the bread dough to rise, yeast also helps to provide some structure to the bread. When water and flour are mixed together, the two proteins in the flour called glutenin and gliadin combine with the water to create gluten. This gluten is responsible for the strength and the structure of the bread and the yeast in the dough contributes to gluten structure as well! When dough is kneaded, the yeast inside is still active, releasing bursts of carbon dioxide. These bursts of gas move around more water and protein molecules, giving them a chance to form more gluten. Along with aiding in the creation of a better gluten structure, the yeast in the dough also helps to create complex flavors within the bread. When fermentation process starts within the bread, enzymes in the yeast start breaking down starch into more flavorful sugars. The yeast uses these sugars, as well as sugars already present in the dough, to produce not only carbon dioxide and alcohol but also flavorful byproducts such as organic acids and amino acids. A multitude of enzymes encourages all kinds of reactions that break big chains of molecules into smaller ones—amylose and maltose into glucose, proteins into amino acids.

At the beginning of fermentation, enzymes in the yeast start breaking down starch into more flavorful sugars. The yeast uses these sugars, as well as sugars already present in the dough, and produces not only carbon dioxide and alcohol but also a host of flavorful byproducts such as organic acids and amino acids. A multitude of enzymes encourages all kinds of reactions that break big chains of molecules into smaller ones—amylose and maltose into glucose, proteins into amino acids.

As fermentation proceeds, the dough becomes more acidic. This is due in part to rising levels of carbon dioxide and the presence of more flavorful organic acids like acetic acid (vinegar) and lactic acid being formed from the alcohol in the dough. The acidity of the dough causes more molecules to break down. However, eventually the amount of alcohol formed starts to inhibit the yeast's activity. In short, yeast is not only a leavening agent, but also a provider of gluten structure and flavor.

Baking Soda and Baking Powder-Know the Difference

Baking soda and baking powder function like yeast by producing carbon dioxide gas in order to give baked goods their characteristic puffy texture. However, the similarities baking soda and baking powder tend to end there, since both perform two different reactions when put into your sweets.

• Baking Soda-Let the Alkaline Live

Like yeast and baking powder, baking soda creates the carbon dioxide that lets cakes and cookies rise. However, the way this is done is very different to that of yeast. Rather than through fermentation, the alkaline in the baking soda combines with acidic ingredients (buttermilk, sour cream, etc...) to create the carbon dioxide; however, too much of a good thing can be dangerous. If too much leavener is added, the carbon dioxide bubbles will build up, collect, and burst, causing baked goods to become flat. Other than allowing pastries to rise, baking soda also promotes browning in foods, creating deeper, complex flavors. This tasty addition is a direct result of the Maillard (MAY-ard) reaction. The Maillard reaction is when carbohydrates and proteins are heated together and the sugar (from the carbohydrates) and the amino acids (from the proteins) combine to form hundreds of new, distinct flavor compounds. This reaction happens when an amino acid molecule is split apart, with acid end being acidic and the amino end being a an alkaline. When the alkaline end reacts with sugars, the browning process begins to occur. Even though baking soda isn't a natural leavener like yeast, it still causes some of our favorite desserts to rise and help improve the flavor as well.

• Baking Powder-Two for the Price of One

Like yeast and baking soda, baking powder causes baked goods to rise due to the production of carbon dioxide. However, baking powder holds many traits that make it different from other leaveners, literally. Baking soda is a combination of baking soda and cream of tartar, a very acidic powder. When both of these are combined with cornstarch (to prevent the basic baking soda and acidic cream of tartar from mixing), they create baking powder. Since a moist, acidic environment is required for baking soda to produce carbon dioxide, baking powder is usually used as an ingredient used when the batter has no natural acidity. Another reason baking powder is unique is that it comes in two different forms: single-acting baking powder (which only has one acid combined with the baking soda—a quick-acting acid that begins to work when liquid is added to the batter) and double-acting baking powder (has two acids added to the baking soda, the second acid usually being sodium aluminum sulfate). While the single acting begins to work as soon as it's exposed to liquid, the double acting begins to work only when the dish is put in the oven, after the temperature has climbed above 120 degrees. In terms of which baking powder is the best, most people recommend using double-acting baking powder in all recipes. Baked goods rise higher since most of the rise with baking powder occurs at oven temperatures. Double-acting baking powder also provides sufficient lift in the oven to allow you to bake frozen (unbaked) dough. Single-acting baking powder, on the other hand, doesn't provide sufficient leavening for doughs with little liquid such as scones or muffin. With two unique formats and a unique way of activating, baking powder is an essential for any cook's kitchen.

Unorthodox Leaveners

Here are some other things that function like leaveners from KingArthurFlour.com:[1]

• Air

The most basic leaven is simply the air that is captured in a dough or batter. This air is created and trapped by a number of different processes while dough is being mixed.

• Beating and creaming

Don't minimize the importance of these steps; give them the time that's required. Electric mixers have greatly simplified the task of beating sugar, butter and eggs into a light and creamy emulsion for cake, or of making egg whites into meringue. When a recipe calls for 10 minutes of beating-do it!

• Flour

Fluff up your flour before sprinkling it into a measuring cup. Aerated flour will get whatever you're baking off to a much lighter start. (One of the first things a King Arthur employee learns when taking our basic bread-baking class is to take a flour scoop and fluff up the first several inches of flour in its container.)

• Fats

The way you incorporate fat into a dough or batter also increases the amount of air you add. Creaming butter and sugar together incorporates air, both through the action of the beaters, and because jagged sugar crystals "grab" air as they come to the surface. Vegetable oil will produce a heavier product because it just doesn't contain as much air as butter. Also, the water in butter, when heated in the oven, expands and turns to steam; this also helps create a lighter baked good.

• Eggs

Most recipes calling for eggs have them beaten until they're light and lemon-colored; that's the signal that they've incorporated an appropriate amount of air. Egg whites can be beaten until they've ballooned with air and become meringue. And if you beat eggs together with fat (e.g., creaming eggs and butter), you produce an emulsion that can hold more air than either alone.

• Liquids

Cool liquids have more oxygen than warm ones. We're not advocating cold necessarily, but use cooler (cool tap water, milk from the fridge) rather than warmer, unless directed otherwise.

• Sweeteners

Dry sugars will capture more air in a batter or dough than liquid sweeteners. This isn't to say you shouldn't use honey or molasses or maple syrup; when liquid sweeteners are used, the recipe calls for another type of leavening to raise the batter sufficiently.

Other Adjuncts

• Z, address this

Recipes

Tarts

Stephanie and Brandon's Chocolate Pecan Tarts

Pie Crust Recipe:

• 3/4 cup all-purpose flour
• 1/2 stick unsalted butter, cold and diced
• 1 tablespoon granulated sugar
• 1 tablespoon milk

Directions: 1. In a food processor, add the flour, unsalted butter, and sugar. Pulse until it looks like fine sands. If not using a food processor, beat with a hand-held pastry cutter until mixture is fine. After, add in the milk and pulse until it forms a ball. 2. Transfer to a clean working surface and flatten a little. Roll out right away and cover with a plastic wrap. Store in the refrigerator before using.

Chocolate Pecan Filling:

• 2/3 cup sugar
• 1/3 cup margarine or butter, melted
• 1 cup corn syrup
• 1/2 teaspoon salt
• 3 eggs
• 1 cup pecan halves or broken pieces

Directions: 1. Beat sugar, margarine, corn syrup, salt and eggs with hand beater or electric mixer. Stir in pecans. 2. Line tart plates with the pie crust. Make sure uncooked crust is no more than an 1/8 inch thick. 3. Carefully pour 1/8 cup of chocolate pecan filling into each shaped tart. 4. Top with more crushed pecans, if desired. 5. Bake at 375 for approximately 15 minutes. 6. Let cool and enjoy! :)

Rachel & Z's Strawberry Jam Tarts

Tart Recipe:

• 3 cups all purpose flour
• 1 tbs sugar
• 1 1/2 tsp kosher salt
• 1 cup cold butter
• 1/2 cup ice water
• 1 large egg yolk
• 1 tsp vinegar

Directions: Use a food processor to combine the flour, sugar, and salt in bowl. Cut the butter into small cubes about 1/2 inch thick. Add to flour mixture, until there is only pea-sized lumps left. Whisk together ice water, egg yolk, and vinegar in separate bowl. Pour liquid mixture into cut flour. Shape the dough into a ball. Pour the dough onto a floured surface and knead quickly and lightly. Divide the dough in half, wrap and refrigerate for at least 30 minutes.

Strawberry Jam:

• 4 lbs strawberries
• 2 lbs granny smith apples
• 1/2 cup fresh lemon juice
• 5 cups sugar

Directions: Wash, hull and cut the strawberries in half or quarters. Peel, core and chop the apples into smaller than 1/2 inch pieces. In an 8-quart pan, stir together the strawberries, apples, and lemon juice. Bring the mixture to a boil, stirring constantly. Add the sugar and stir until it is dissolved. Somewhat boil, stirring frequently, until the jam reaches 212 deg F (about 15-25 minutes).

Sam & Gabby's French Apple Pie Tarts

Tart Recipe:

• 3/4 cup sugar
• 1/4 cup all-purpose flour
• 1 dash of salt
• 2 tbs butter
• 1 large egg yolk
• 1/4 cup lemon juice

Directions: Pre-heat oven to 425. Mix dry ingredients together in one bowl. Once finished, add chilled butter to the mixture and use a pastry cutter to mix the butter in until it is the size of small rice grains. Make a hole in the dry ingredients to put the egg and lemon juice into. Knead together and divide dough into two. Roll into dough balls and wrap both with cling wrap. Let sit in the refrigerator for 30 minutes to chill.

French Apple Pie Crumble:

• 1 cup all-purpose flour
• 1/2 cup chilled butter
• 1/2 cup brown sugar
• 5 cups thinly sliced granny smith apples
• 1 cup thinly sliced honey crisp apples
• 1/2 tsp ground cinnamon

Directions: Mix sugar, flour, cinnamon, and salt together in one bowl and then add the bowl of cut up apples. Microwave tart insides inside a microwave for 5 minutes until soft. Fill tart pan with cut out tart bottoms. Use a mason jar lid to cut the pastries after they've been rolled out 1/8 of an inch thickness. Fill tarts with apple pie filling. Use the crumble and sprinkle over filled tarts by using a tablespoon of crust mixture. Stick in oven for 15-20 minutes or until browned.