Baking bread at home is common nowadays and seeing the trend you also decide to bake one for your family. Fully geared up, browse through the internet. So many eye-catching pics of bread, so many easy recipes. After a lot of comparisons, reading, struggling with everything, you finally make up your mind on one recipe. But, what this 'one packet yeast' means? What is instant yeast? What is active dry yeast? Are they different? Or just different names of the same thing? One recipe says proof yeast other doesn't... Why so? And what does proofing means?

Friends, this is my story. Around 10 years back, when I decided to try my first bread, many such questions popped up in my mind. I am sure, you too must have faced such questions... if not all at least some, Right?

So, let us try to understand this complex yeast. Understanding yeast in baking is very important. Once you have mastered that, half the battle is won.

As you all know through my earlier article that there are three main leavening agents--- Baking Soda, Baking Powder and Yeast. The first two we have already discussed in the post titled Difference Between Baking Soda and Baking Powder. Now let us discuss yeast.

Related articles:

Must Read:  Basic Steps Involved In How To Make Bread

What Is Yeast?

Yeast is a single-celled microorganism related to mushrooms. Out of more than 1500 species of yeast, just one, Saccharomyces cerevisiae  (which means sugar-eating fungi), is used in the kitchen. Other than baking bread, the same species of yeast is also used for brewing beer, making wine, and other food products such as soy sauce and vinegar. It is called both Baker's yeast as well as Brewer's yeast.


What is the Function of Yeast in Baking?

  • Being a leavening agent, the function of yeast is to convert fermentable sugars present in the dough into carbon dioxide and ethanol. The carbon dioxide thus produced helps the bread rise.
  • Yeast does this by feeding on the sugars in the flour and expelling carbon dioxide in the process. This gas with no place to go but up fills the dough with thousands of balloon-like bubbles. Once the bread is baked, these bubbles give the loaf its airy texture.
  • Dough made with yeast rises once, then punched down, then rises again and finally goes into the oven. In the oven, heat rouses the yeast to one last great expulsion of carbon dioxide before they reach 140 degrees Fahrenheit and die.
  • Yeast contributes to flavor as well. Hence, adding more yeast to a recipe won't cause bread to rise more but will produce a more intense yeast flavor.


What are Different Types of Yeast?

Baker's yeast is available in various forms, which differ mostly by the content of moisture in it.  There are mainly two types of yeast:

  • Fresh Yeast
  • Dry Yeast
    • Active dry yeast,
    • Instant yeast and
    • Rapid rise yeast.  

We will see how they are different from each other but before that let us see what these terms mean.

Fresh Yeast

  • Fresh yeast is also known as Cake yeast or Compressed yeast. It is called cake yeast only because it is sold in the form of tiny cakes. You get these in the refrigerated section of bakery shops or supermarkets.  It is made from a slurry of yeast and water with enough of its moisture removed so that it can be compressed into blocks.
  • It needs no proofing and can be added directly to the flour or dissolved with water first. Dissolving in water helps it to disperse fully.
  • Despite the fact that it leavens beautifully and gives a slightly sweet flavour to the baked goods, it is not at all advisable for home baking. It is highly perishable and used only by professionals. It lasts only for about 2 weeks even if refrigerated.
  • Once I also bought it but had to throw it as couldn't use it fully. Also, it was difficult to use in terms of measuring it as it was very sticky. It is measured in grams and measuring 3-4 grams was not easy. So please don't be tempted to buy it at any cost unless you plan to do it commercially.
  • If the recipe calls for fresh yeast and you have active dry yeast or instant yeast then you can easily interchange these by making certain changes in the measurements.


Active Dry Yeast

  • It is a dry granular yeast.  These are granules of live yeast cells wrapped in dry dead cells. Thus, it is an active yeast but remains dormant until it comes into contact with liquid.
  • Before working with active dry yeast, it must be activated or proofed by dissolving it in warm water. The resulting foam is confirmation that the yeast is still alive...
  • Active Dry yeast has a long shelf life. If not opened, remains good for one year even at room temperature. Once opened, remains good for 6 months in the refrigerator and even up to a year if kept in the freezer. If kept in the freezer, then you can use directly without thawing it.
1 Package Active Dry Yeast = 2.25 tsp or 7 gms or 0.25 ounce


Instant Yeast

  • Instant yeast is also granular yeast but its granules are much smaller than that of Active Dry Yeast. It has a very high percentage of live cells. It is ground much finely and thus absorbs moisture faster, rapidly converting starch and sugar into carbon dioxide.
  • It can be added directly to the flour. It doesn't require to be proofed by dissolving in warm water. However, still, some people proof it by adding it in warm water just to ensure that the yeast is active and not expired.
  • At times a very small amount of ascorbic acid is added to the instant yeast to preserve it. Due to this, it can be preserved for almost a year at room temperature.


Rapid Rise Yeast

  • Rapid rise yeast is a type of instant yeast only but has even more fine granules. Since the granules are very small they dissolve easily and rise quickly and hence the name was given rapid rise to it.
  • But very quick rising affects the taste of bread adversely.  Bread made with rapid rise yeast does not have as much flavour as the bread made with other yeasts.
  • It is also called bread maker's yeast or bread machine yeast.
  • No doubt it saves a lot of time. If using Rapid Rise yeast then bread recipe requires only one rise. First rise is replaced by 10 minutes rest and you don't have to punch the dough afterwards. Thereafter the dough is shaped into loaf/doughnuts etc and left for the second rise.
  • Rapid rise yeast cannot be interchanged with any other yeast. So, if the recipe calls for rapid rise yeast then use it that only.


Difference Between Different Types Of Yeast

To summarize, Fresh Yeast, Active dry yeast and Instant yeast are more or less the same except for the following two differences :

  • Moisture content and hence the physical looks (appearance).
  • Active dry yeast needs to be proofed or bloomed in warm water before adding to the flour, whereas, Fresh yeast and instant yeast are added directly to the flour.

They all follow the same principle of dough rising once, then punched down, then rise again and finally go into the oven.

These can be used interchangeably, with variations in measurements.


Conversion Chart

  • Instant yeast is used less in quantity as compared to Active dry yeast.
  • So, multiply the quantity of Active  Dry yeast by 0.75 to convert it into instant yeast.
  • And, multiply the quantity of Instant Yeast by 1.25 to convert it into Active Dry Yeast.

Or, in more simple words,

1 tsp Active Dry Yeast   =  3/4 tsp Instant Yeast

1 tsp Instant Yeast   =  1.25  tsp Active dry Yeast.

8.5 Grams Fresh Yeast = 1 tsp Instant Yeast

5.7 Grams Fresh Yeast = 1 tsp Active Dry Yeast


How Much Yeast To Use in Baking Bread?

Lower the amount of yeast more is the rising time hence more flavour in the bread.

The exact amount of yeast needed to rise bread dough depends on three things:

  • Type of yeast used: As discussed above.
  • The temperature of the dough:  Whether hot or cold, it is advised not to use much yeast. It will rise slowly taking a long time in winters whereas in summers it will take less time. This is because a higher temperature makes the yeast more active.
  • The length of rising time:  Less yeast takes long time to rise and vice-versa.  The rising time can be controlled by varying the amount of yeast and the temperature of the rise. For example, a recipe may call for 2 teaspoons of yeast and 2 hours of rising, but if you’re going to be out for the day, you can reduce the amount of yeast to ½teaspoon, rise the dough in the refrigerator overnight, and finish the bread the next day. The lower temperature and longer rising time will allow the yeast to multiply more gradually and create a more complex flavor.


How to proof yeast?

Read in detail in my post Basic steps involved in making bread


What is meant by terms like proofing, knockdown, kneading the bread dough, etc.

Read in detail in my post Basic steps involved in making bread


 Why my bread didn't rise?

You took utmost care in everything yet your bread didn't rise. Why?

Look for the possible reasons...

  • Expired Yeast - While using active dry yeast,  it is first bloomed/activated in warm water, making it clear whether the yeast is good or not. But in the case of instant yeast, it is difficult to make out. This is the reason that though not required but still, some people activate it in warm water before using it. If the yeast is active, it will produce a bubbly mass within 10 minutes. If doesn't then the yeast is not good enough, so better put it in the bin and buy a new packet of yeast. Always buy good quality yeast.
  • The temperature of the water - Yeast needs just warm water to activate. The ideal temperature of water for proofing yeast is 105 degrees Fahrenheit. It simply means warm water in which you can dip your finger comfortably for few seconds. Hotter than this will kill yeast and if cooler than yeast will not activate fully.
  • Salt - Salt is a yeast inhibitor and it is best to add it in a way that it is not touching the yeast. It's better to use non-iodized salt because of iodine attacks yeast activity. Remember reading Kosher salt in recipes? Kosher salt is basically salt without iodine.
  • The dough was not punched down - After the first rise, the dough is punched down or knocked down. This simply means to deflate the dough, shape it and leave it for the second rise. If the dough is not deflated properly then alcohol built up during the first rise doesn't get released and creates a toxic environment that kills the yeast. So always punch down the dough properly.


 Can Baking Soda/Powder Be Used In Place Of Yeast?

The short answer is "No" for the simple reason that both of them work in fundamentally different ways and should not be used as a substitute for each other.

Recipes that use Baking soda/powder rely on a chemical reaction for their rising properties. They react with acid/liquid and heat to create gases and create rising action. To aid this process many times we add lemon juice or buttermilk to the recipe, to support the rising action. The dishes need not be pre-prepared. And rising takes place during baking only.

Whereas, in the case of yeast, the dough needs to be allowed to "rise" before baking. In the process, they act on the sugar in the dough to create gases and alcohol, something which lends a very distinctive flavour and aroma. Yeast is most effective when used with a dough which is high in gluten, a starchy substance found in wheat which also aids in trapping the gasses in the dough. And that is why it is most effective with wheat flour dishes.

This was regarding some aspects of baker's yeast.

I hope you have found this post useful. Do share your feedback as you know your feedback fuels my enthusiasm to post more good recipes.

Thank you for reading this post. If you have liked this recipe then do let me know by leaving a comment below. Your feedback fuels my enthusiasm. You may share this post with your dear ones by clicking on the little buttons below. You may follow me on  Facebook   Pinterest  Twitter  Instagram(#samirasrecipediary) too. for latest recipe updates. Thank you!

Stay Healthy…Stay Happy

Gratitude: My heartfelt gratitude to the following websites as the above article on the understanding of yeast is based on the information given therein:-