Science: What is Gluten? Here's How to See and Feel Gluten

Summary

This video script explores the role of gluten in baking, contrasting cake flour with bread flour. Gluten, formed by proteins glutenin and gliadin in wheat flour, creates an elastic network that traps air, allowing bread to rise. The experiment demonstrates gluten's elasticity by washing away starch from two doughs, revealing pure gluten. Cake flour's weak gluten is easily torn, while bread flour's strong gluten can be stretched thin. The video concludes that bread flour's flexible gluten is ideal for high-rise breads, whereas cake flour's lower gluten content prevents cakes from becoming tough.

Takeaways

• 🍞 Wheat flour contains two important proteins: glutenin and gliadin.
• 💧 When mixed with water, glutenin and gliadin bond together to form gluten.
• 🎈 Gluten forms an elastic network that traps air, allowing bread to rise.
• 🍰 Cake flour has less protein and forms weaker gluten, suitable for cakes.
• 🥖 Bread flour has more protein, creating strong and elastic gluten for bread.
• 🧼 Washing dough with water can remove starch, leaving behind pure gluten.
• 📏 High protein bread flour gluten can be stretched thin without tearing.
• 🍰 Cake flour's lower protein content provides structure without toughness in cakes.
• 🥞 All-purpose flour is versatile for foods that require moderate gluten development.
• 🔍 The experiment visually demonstrates the importance of gluten in different baking applications.

Q & A

What is gluten and why is it important in baking?

Gluten is an elastic network of proteins formed by the combination of glutenin and gliadin proteins found in wheat flour when mixed with water. It's important in baking because it traps air, allowing breads to rise and providing structure to baked goods.

What are the two proteins that combine to form gluten?

The two proteins that combine to form gluten are glutenin and gliadin.

How does gluten help bread rise?

Gluten traps air, forming an elastic network that expands as it fills with gas bubbles and swollen starch granules, which allows the bread to rise.

What type of flour was used in the experiment to demonstrate gluten's properties?

Two types of flour were used: cake flour, which contains less protein and forms weaker gluten, and bread flour, which contains more protein and forms a strong, elastic gluten.

Why is cake flour different from bread flour in terms of gluten formation?

Cake flour contains less protein and is often bleached, which weakens the proteins. This results in less gluten formation, making it suitable for cakes that require a lighter texture.

What property of bread flour makes it ideal for bread making?

Bread flour has a higher protein content, usually between 12 to 14 percent, which allows it to form a large amount of flexible gluten. This gluten acts like a balloon, trapping air and creating higher rising loaves.

How was the gluten separated from the starch in the experiment?

The gluten was separated from the starch by placing the dough in a mesh strainer and washing it under running water, which removed the starch until the water ran clear.

What was the result of washing away the starch from the dough?

After washing away the starch, two piles of essentially pure gluten were left. The cake flour dough formed a small amount of weak gluten, while the bread flour dough formed a large ball of highly resilient, rubbery gluten.

How did the presenter demonstrate the elasticity of bread flour gluten?

The presenter demonstrated the elasticity of bread flour gluten by inflating it like a balloon with compressed air.

What is the role of all-purpose flour in baking?

All-purpose flour is suitable for a variety of foods that fall between the extremes of cake and bread, such as pie dough, harder muffins, and cookies. It has a moderate protein content that provides structure without being too tough.

What can one remember from this experiment when kneading pizza dough or folding cake batter?

One can remember the importance of gluten in providing structure and elasticity to dough, and how different types of flour affect the gluten formation and the final texture of the baked goods.

Outlines

00:00

🍞 Understanding Gluten in Flour

This paragraph explains the role of gluten in baking. Gluten is a protein network formed by two proteins, glutenin and gliadin, found in wheat flour. When combined with water, these proteins bond together to create an elastic structure that traps air, allowing bread to rise and providing structure to baked goods. The paragraph describes an experiment where two doughs are made with cake flour (low protein content) and bread flour (high protein content). The starch is washed away from each dough to reveal the gluten, showing the difference in gluten formation between the two types of flour.

Keywords

💡Gluten

Gluten is a protein composite found in wheat flour that gives elasticity to dough. In the video, gluten is described as an elastic network formed by two proteins, glutenin and gliadin, which bond together when mixed with water. This network traps air, allowing bread to rise and providing structure to baked goods. The video uses an experiment to visually demonstrate the strength and elasticity of gluten derived from bread flour versus cake flour.

💡Wheat Flour

Wheat flour is a key ingredient in many baked goods and is the primary source of gluten. The video explains that all wheat flours contain glutenin and gliadin proteins, which are crucial for the texture and rise of baked products. Different types of wheat flour, like bread flour and cake flour, contain varying amounts of protein, affecting the amount and quality of gluten they produce.

💡Glutenin

Glutenin is one of the two proteins in wheat flour that combine with gliadin to form gluten. The video script mentions that glutenin changes shape in the presence of water and bonds with gliadin to create the gluten network. This network is essential for the rise and texture of bread and other baked goods.

💡Gliadin

Gliadin is the second protein in wheat flour that, together with glutenin, forms gluten when mixed with water. The script explains that gliadin's interaction with glutenin is what creates the elastic properties of gluten, which is vital for the leavening process in baking.

💡Elastic Network

The term 'elastic network' refers to the structure formed by gluten in the video. It is described as an elastic web that can trap air, similar to a balloon, and is responsible for the rise of bread and the structural integrity of cakes. The video uses this term to illustrate how gluten functions within baked goods.

💡Cake Flour

Cake flour is a type of wheat flour with a lower protein content, typically between six and eight percent. The video explains that because of its lower protein content, cake flour forms a weaker gluten network, which is ideal for creating tender cakes and delicate baked goods that should not be too tough or chewy.

💡Bread Flour

Bread flour is highlighted in the video as having a higher protein content, usually around 12 to 14 percent. This higher protein level results in a stronger, more elastic gluten network, which is essential for the rise and structure of bread. The video demonstrates this by showing how bread flour can form a large, resilient ball of gluten.

💡Starch

Starch is a carbohydrate found in flour that provides structure and texture to baked goods. In the video, starch is mentioned in the context of washing it away from the gluten to isolate and examine the gluten's properties. The process of washing away starch helps to visually distinguish the gluten's role in baked goods.

💡Rise

The term 'rise' in the video refers to the expansion of dough or batter during baking due to the trapped air and gas bubbles within the gluten network. The rise is crucial for the texture and volume of bread and other baked goods, with the video emphasizing the importance of gluten in achieving a good rise.

💡Experiment

The video describes an experiment where two doughs made from cake flour and bread flour are washed to remove starch, leaving behind pure gluten. This experiment visually demonstrates the difference in gluten strength and elasticity between the two types of flour, illustrating the concept in a tangible way.

💡All-Purpose Flour

All-purpose flour is mentioned as a versatile type of flour that falls between cake and bread flour in terms of protein content. The video suggests that it is suitable for a wide range of baking applications, providing a balance of gluten formation needed for structures that are not too delicate or too chewy.

Highlights

Wheat flour contains two important proteins: glutenin and gliadin.

In the presence of water, glutenin and gliadin bond together to form gluten.

Gluten has the ability to trap air, similar to a balloon.

The gluten network is filled with swollen starch granules and gas bubbles, allowing breads to rise.

Cake flour contains the least amount of protein, usually between six and eight percent.

Bread flour contains the most amount of protein, usually around 12 to 14 percent.

Cake flour is often bleached, which weakens the proteins.

Bread flour is generally not bleached, allowing for stronger gluten formation.

The experiment involved washing away starch from dough to isolate gluten.

Cake flour formed a small amount of weak gluten that can be easily pulled apart.

Bread flour formed a large, resilient, rubbery gluten ball.

The bread flour gluten ball was elastic enough to be inflated like a balloon.

High protein bread flour is used for breads to create flexible gluten for higher rising loaves.

Cake flour's lower protein content provides just enough gluten for structure without toughness in cakes.

All-purpose flour is suitable for foods that fall between the extremes of bread and cake.

The experiment demonstrates the importance of gluten in baking.

Seeing the gluten in its pure form helps to understand its role in different baked goods.

Transcripts

[Music]

we use wheat flour in countless recipes

from chewy loaves of rustic bread and

pizza dough to tender cakes and some

muffins all of these baked goods rely on

something called gluten how does this

work

first let's start with a simple question

what is gluten all wheat flours contain

two important proteins gluten in and

gliadin now in the presence of water

these two small proteins change shape

and bond together this creates an

elastic network of proteins called

gluten which has the ability to trap air

much like a balloon

this gluten network fills with swollen

starch granules and gas bubbles allowing

breads to rise and cakes to gain some

gentle structure now here in the test

kitchen we've long known that gluten is

important in baking but mainly we've

done a lot of talking not a lot of

showing so what is it on a tangible

level can you see it can you feel gluten

i ran a simple experiment to find out

just that

i made two basic doughs by mixing flour

and water in a food processor until a

smooth ball formed now for one dough i

use cake flour which contains the least

amount of protein of all the different

types of flour that you can find at the

grocery store between six and eight

percent usually in addition cake flour

is often bleached which further weakens

the proteins now for the other one i use

bread flour which contains the most

amount of protein usually running about

12 to 14 percent and is generally not

bleached

so you can see here i have two balls of

dough each containing a different amount

of gluten but you can't actually see

that because surrounding that gluten is

a whole lot of starch the next step

believe it or not i washed the starch

away i placed each dough in a mesh

strainer and massaged them under running

water to wash away all the starch once

the water ran clear a sign that the

starch was gone i was left with two

piles of essentially pure gluten as you

can see the differences in appearance

and texture of the two are dramatic

the low protein cake flour formed a very

small amount of really weak gluten you

can pull it right apart

on the other hand high protein bread

flour formed a large ball of highly

resilient rubbery gluten it can be

stretched very thin without tearing

to show just how elastic this bread

flour gluten ball is i'm going to try

and do something a little bit crazy i'm

going to treat it like a balloon and

inflate it with compressed air

[Music]

so what did we learn from this

experiment well we use high protein

bread flour for breads because it

develops a lot of very flexible gluten

which as we've seen

acts like a balloon trapping air and

creating higher rising loaves now for

cakes we want just enough gluten to

provide a bit of structure without

turning them tough we turn to cake flour

for its lower protein content and reduce

gluten potential

all-purpose flour as its name suggests

is good for a lot of foods that fall in

between these extremes such as pie dough

hardier muffins and cookies

so next time you're kneading pizza dough

gently folding a cake batter or

considering swapping one type of flour

for another we hope you remember this

experiment this is one case where seeing

really is believing

[Music]

you