Why is yeast used in bread making?
This question arose today at lunch, and we tried to explain it in various ways:
It gives the soft (spongy) consistency;
It improves the nutritional content;
It makes bread more digestible;
It improves the taste.
We were unable to say which ones are true, and if more than one, which is the main reason. It should be something simple I guess, because yeast has been used since ancient times.
Wiki talks about consistency, but I would like some more expert advice.
EDIT: I know there are yeast-free breads, like Italian's piadina or Indian's chapati and roti, and even Mexican's tortilla. And that's where the question originates from, because the asker is from Pakistan.
Best Answer
There are various types of bread without yeast. Unleavened Jewish Passover bread, for one, and soda bread for another. Unleavened bread doesn't have the spongy texture.
Basically, yeast has two uses in baking. 1. The spongelike structure and 2. Taste.
Pictures about "Why is yeast used in bread making?"
Quick Answer about "Why is yeast used in bread making?"
Yeast has two primary functions in fermentation: To convert sugar into carbon dioxide gas, which lifts and aerates the dough. To mellow and condition the gluten of the dough so that it will absorb the increasing gases evenly and hold them at the same time.Why is yeast used to make breads?
Baker's yeast is the common name for the strains of yeast commonly used in baking bread and other bakery products, serving as a leavening agent which causes the bread to rise (expand and become lighter and softer) by converting the fermentable sugars present in the dough into carbon dioxide and ethanol.What is the purpose of adding yeast?
Yeast works by serving as one of the leavening agents in the process of fermentation, which is essential in the making of bread. The purpose of any leavener is to produce the gas that makes bread rise. Yeast does this by feeding on the sugars in flour, and expelling carbon dioxide in the process.Why is Yeast added for making bread | Basic Science | Fermentation by yeast
More answers regarding why is yeast used in bread making?
Answer 2
A better answer in wiki would be under this link Leavening Agents
It explains the different leavening agents and their desired outcome. If it’s not the info you are looking for then maybe you need to compare yeast bread to unleavened and non-yeast breads.
Unleavened and Non-yeast Breads; Dense, drier, cracker like either bland in flavor (which a lot of people like) and needs added flavoring or topping, butter, egg, fruit, seeds, nuts and others.
Yeast Breads; Can just be made with flour, water, yeast a little salt or a little sugar to activate/feed the yeast further. Yeast gives you the flexibility to knead or not to knead (completely different subject) and supports the structure which lends to the texture. Let’s not forget that aroma and flavor. Heaven! There are various Dry Yeasts, they take time to develop flavors and can last a longer time in the fridge. Cake yeasts, (looks like wrapped butter) already has developed flavor and has a much shorter shelf life.
Although this is just basic info, it maybe enough to answer your question.
Sources: Stack Exchange - This article follows the attribution requirements of Stack Exchange and is licensed under CC BY-SA 3.0.
Images: Mariana Kurnyk, Katerina Holmes, Piotr Arnoldes, Anna Rye