Why ethanol vapor doesn't get trapped in bread dough, while CO2 does?

[lost captain]

TL;DR Summary

Why ethanol vapor doesn't get trapped in bread dough, like CO2 ? They are both gases in the oven but one escapes the complex gluten structure while the other get traped inside

In ethanol fermetation and especially when baking a bread: "Yeast organisms consume sugars in the dough and produce ethanol and carbon dioxide as waste products. The carbon dioxide forms bubbles in the dough, expanding it to a foam."
We learn that ethanol leaves the bread, it escapes the gluten structure, it vaporizes but CO2 gets trapped inside. Why is that?
They are both in gas form(inside the oven), they are both small molecules, they are both in the same oven temperature hence their kinetic energy will be the same.

 

[256bits]

TL;DR Summary: Why ethanol vapor doesn't get trapped in bread dough, like CO2 ? They are both gases in the oven but one escapes the complex gluten structure while the other get traped inside

In ethanol fermetation and especially when baking a bread: "Yeast organisms consume sugars in the dough and produce ethanol and carbon dioxide as waste products. The carbon dioxide forms bubbles in the dough, expanding it to a foam."
We learn that ethanol leaves the bread, it escapes the gluten structure, it vaporizes but CO2 gets trapped inside. Why is that?
They are both in gas form(inside the oven), they are both small molecules, they are both in the same oven temperature hence their kinetic energy will be the same.

Hi Lost Captain
The full quote from Wiki includes an alcoholic content of bread. ( the high value from the reference, rather than a range )
" Ethanol fermentation causes bread dough to rise. Yeast organisms consume sugars in the dough and produce ethanol and carbon dioxide as waste products. The carbon dioxide forms bubbles in the dough, expanding it to a foam. Less than 2% ethanol remains after baking"

I see nothing of

We learn that ethanol leaves the bread,

so it might be worthwhile to explain where you got that idea from.

Hint:
At room temperature, is CO2 a gas or a liquid?
At room temperature, is ethanol a gas or a liquid?
Is there any water in the bread, and if so, how might that effect the formation of the bubbles, be it either from CO2 or ethanol being the main culprit responsible for the leavening?

 

[lost captain]

so it might be worthwhile to explain where you got that idea from.

Most of the ethanol vaporizes, since the amount left on the bread is pretty less than the ethanol that was produced.
That's why i said ethanol leaves the bread.
(Of course i searched that online before making that statement, my source wasn't any scientific paper, just a typical google search)
So compared to the CO2 that is being traped inside the gluten structure, why the same doesn't happen to the ethanol vapor?

At room temperature, is CO2 a gas or a liquid?
At room temperature, is ethanol a gas or a liquid?

At room temperature CO2 is gas and ethanol is a liquid. But still even before puting the bread in the oven as long as the ethanol fermentation has started, CO2 gas gets trapped inside while ethanol vaporizes
In the oven they are both gases, shouldn't ethanol also be responsible for the creation of bubbles inside the dough, bubbles because of ethanol vapor.

Is there any water in the bread, and if so, how might that effect the formation of the bubbles,

Sure there is water, but i cant make the connection...maybe ethanol is diluted in water while CO2 isn't?


Also thank you very much for taking the time to reply.

 

[Mayhem]

Speculation:
At r.t, ethanol is a liquid and CO2 is a gas. Ethanol as it is formed is chemically mixed with water in the dough, whereas CO2 is physically trapped in the dough. Upon baking, the ethanol is therefore free to evaporate along with the water, whereas trapped pockets of CO2 will increase in size and set as the bread bakes. You'll also notice that when you bake bread, there is some bubbling in the dough, so not all CO2 is trapped.

Just a guess.

 

[256bits]

Sure there is water, but i cant make the connection...maybe ethanol is diluted in water while CO2 isn't?

Ethanol is fully soluble in water, wheras CO2 has a solubility very low.
Most of the bubbles produced at room temperature would be comprised of mainly CO2, and some ethanol due to its vapourization pressure at that temp, as well as some water vapour.
Note that the yeast at the beginning will convert the sugars by both processes of aerobic respiration, with production of water and CO2, as well as anaerobic fermentation, with production of ethanol and CO2. The ratio of these chemical procedures progresses from aerobic to anaerobic as the oxygen supply within the bread diminishes.
https://www.engineeringtoolbox.com/gases-solubility-water-d_1148.html

The bubbles formed at room temperature are mainly of CO2 composition.
In the oven as the temperature rises, the bubbles increase in size. A bit more ethanol vapourises contributing to some increase in size. Until the yeast is completely dead due to the heat, more CO2 is being produced. Most of ethanol is still being absorbed by the water in the bread.

The final result is that the bubbles form from CO2 gas being given off from the yeast, the ethanol remains as a soluable mixture with the water in the bread.

Some evaporation of water and alcohol does occur during baking, but to what extent I would have to investigate, but just enough to give the bread its body.
A bread without enough water content is labelled as being dry.

 

[256bits]

the ethanol is therefore free to evaporate along with the water

Not all the water nor ethanol is removed from the bread during baking.
A fairly good percentage remains.
Nothing like the smell of freshly baked bread from what does escape.

 

[256bits]

There is this
https://dietandfitnesstoday.com/water-in-bread.php
of which some percentage, or grams, is alcohol in 100g.

Below is a summary list for the top twenty bread items ranked by the amount or level of water in 100g.

1. Breadfruit, raw : 70.65g
2. Bread stuffing, cornbread, dry mix, prepared : 64.90g
3. Bread stuffing, bread, dry mix, prepared : 64.77g
4. Bread, kneel down (Navajo) : 52.96g
5. Bread, wheat, sprouted : 50.88g
6. Bread, boston brown, canned : 47.20g
7. Bread, wheat, sprouted, toasted : 46.61g
8. Bread, reduced-calorie, oat bran : 46.00g
9. Bread, reduced-calorie, rye : 46.00g
10. Bread, reduced-calorie, oatmeal : 44.00g
11. Bread, oat bran : 44.00g
12. Bread, gluten-free, white, made with rice flour, corn starch, and/or tapioca : 42.99g
13. Bread, reduced-calorie, white : 42.90g
14. Bread, cinnamon : 41.93g
15. Bread, rice bran : 41.00g
16. Bread, protein (includes gluten) : 40.00g
17. Bread, french or vienna, whole wheat : 39.81g
18. Bread, reduced-calorie, wheat : 39.60g
19. Bread, white wheat : 39.60g
20. Bread, cornbread, prepared from recipe, made with low fat (2%) milk : 39.10g

 

[Mayhem]

Not all the water nor ethanol is removed from the bread during baking.
A fairly good percentage remains.
Nothing like the smell of freshly baked bread from what does escape.

Of course not, but a significant amount must.

 

[DrJohn]

As water is also formed during the fermentation in bread, and has the highest boiling point of the three - water, ethanol, and carbon dioxide - as a guess, perhaps it too is contributing to the bubble size inside the bread, with more of the carbon dioxide and ethanol escaping than the water?

This is just a suggestion, something that might be happening, perhaps.