What is Yeast?

You Are Here Ask Latisha » Articles » Learning Something New » What is? » What is Yeast?

What is Yeast?


Yeast is a microscopic (very, very small) type of Fungus. It is a living organism. (Microorganism)

It is made up of only one cell (unicellular).

“Like those found in humans, yeast cells are living and natural. They need air to multiply, but the absence of air also has consequences on their development.” Quoted here.

What does it look like?

It has an ovoid (egg-shaped) or spherical shape, and a yellowish color.


How Does it Work?

All living things need to breath to live, but yeast can breath without oxygen (Anaerobic Respiration). Yeast cells thrive on simple sugars. Under the right circumstances when Yeast comes into contact with sugar, the sugar feeds the yeast. The yeast produces CO2 (Carbon Dioxide) and alcohol.

By fermentation, the yeast species Saccharomyces cerevisiae converts carbohydrates to carbon dioxide and alcohols – for thousands of years the carbon dioxide has been used in baking and the alcohol in alcoholic beverages. Quoted here.

What Do You Use Yeast For?

Bread-making, alcohol drinks (wine, beer, etc), nutrition and bio-fuels. Learn More.

Yeast is the driving force behind fermentation, the magical process that allows a dense mass of dough to become a well-risen loaf of bread. Quoted here.

What are the different types of yeast?

Some forms of yeast are Active Dry Yeast (alive), Instant Dry Yeast (Dead) and Nutritional Yeast. Here are more.

Active dry yeast and instant (or rapid-rise) yeast are the two most common yeasts available to us as home bakers. The two yeasts can be used interchangeably in recipes, but active dry yeast needs to be dissolved in water before using while instant yeast can be mixed right into the dough. Quoted here.

Brewer’s yeast (or nutritional yeast) is used as a food supplement. It is dehydrated at high or low temperature. Quoted here.

In the case of dead yeasts (or inactive, i.e. beyond 40°C), the yeast keeps its vitamins and minerals but it cannot be used to make bread: it is an inactive yeast! Quoted here.

Read here to learn-

What’s the Difference? Instant, Active Dry, and Rapid-Rise Yeasts.

Kneading the dough-

When you stir together flour and water, two proteins in the flour—glutenin and gliadin—grab water and each other to form a bubblegum-like, elastic mass of molecules that we call gluten. In bread making, we want to develop as much gluten as we can because it strengthens the dough and holds in gases that will make the bread rise. Quoted here.

To knead the dough is to use your hands to squeeze, pound, work, mold, shape, and manipulate the dough, causing the gluten strands to warm and stretch, creating a springy and elastic dough.

You can also knead with a a mixer equipped with a dough hook, or with a bread machine.

If bread dough is not kneaded enough, it will not be able to hold the tiny pockets of gas (CO2) created by the leavening agent (such as yeast or baking powder), and will collapse, leaving a heavy and dense loaf. Quoted here.

Visit this “Bread Baking Clinic,” to find out if you are over kneading or under kneading.

Here are some more resources to go even deeper into learning about yeast.

Video Resource:



Yeast’s Crucial Roles in Breadbaking

The Science of Kneading Dough

What is Yeast



By |2017-02-22T13:18:52+00:00March 15th, 2015|Learning Something New, What is?|18 Comments

Share This Story, Choose Your Platform!


  1. Monica March 17, 2015 at 4:48 pm - Reply

    So interesting! I’ve been meaning to try out nutritional yeast. I hear vegans use it as a cheese substitute and I’m always looking to cut back on store bought dairy. :)

  2. Terri Presser March 19, 2015 at 3:08 pm - Reply

    Thanks for sharing this with us at Good Morning Mondays, it was a very interesting and informative post, thanks for the hard work in putting it together for us. Blessings

  3. […] Recently, i’ve posted some fun learning post. So if you have ever been curious about Yeast, Cream of Tar-Tar, Lucky Charms Cereal (fun facts). Check them […]

  4. Carolyn Henderson March 20, 2015 at 4:42 pm - Reply

    Interesting. I use yeast all the time and didn’t realize it was a form of fungus. Just out of curiosity, how many yeast cells do you think are in one of the little granules we get in the yeast packs?

    • Latisha Barker March 24, 2015 at 4:54 am - Reply

      Hi Carolyn,

      I’m glad you learned something new today. To answer your question. I really don’t know, but I’ll see if I can find out. Blessings to you.

  5. Brandi Clevinger March 20, 2015 at 5:34 pm - Reply

    I’ve wondered about yeast. That’s interesting information about it. Thanks for sharing it at Inspire Me Mondays!

    • Latisha Barker March 24, 2015 at 4:52 am - Reply

      Hi Brandi,

      Thanks for dropping by. Hope you learn something new.

  6. Kelly @ Mum-bo March 22, 2015 at 7:08 am - Reply

    I had no idea yeast was a fungus! You have enlightened me to this fact. It was also interesting to learn about the different yeasts available – I really didn’t know the difference. Thanks for linking up at Mum-bo Monday

    • Latisha Barker March 24, 2015 at 4:41 am - Reply

      Hi Kelly,

      Glad you learned something new here, I feel like I accomplished what I set out to do. Thanks for visiting.

  7. Erica March 22, 2015 at 1:57 pm - Reply

    So informative! Thank you for sharing at Wordless Wednesday! Hope to see you next week! xoxo

  8. Mindie March 22, 2015 at 6:25 pm - Reply

    Great info! Thanks for sharing on the (mis)Adventures Mondays Blog Hop!!

  9. Letetia Mullenix March 23, 2015 at 1:48 pm - Reply

    I love it when I come agree a ready to go science lesson, disguised in fun. My daughter and I can try baking bread and fulfill her hunger for all things experimental. Thanks for sharing! #MotivateRMday

    • Latisha Barker March 24, 2015 at 4:27 am - Reply

      Hi Letetia,

      I’m glad you like the lesson. It was really fun to put together. Will be doing alot more of these kind of learning post. Hope you and your daughter have fun baking. My daughter and I have fun doing things in the kitchen together. Now she is starting to do some things on her own. Blessings to you and thanks for visiting.

  10. jess March 24, 2015 at 10:53 pm - Reply

    this is really interesting. thanks for sharing this with everyone at Totally Terrific Tuesday! I hope you make it back this week with more goodies!!

  11. […] What is Yeast? by AskLtisha […]

  12. Sabrina October 19, 2017 at 2:11 pm - Reply

    Really great info. I actually dont know that yeast is type of fungus.

Leave A Comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.