If you’re in the process of making bread and realise you have weighed out the yeast incorrectly, you’ll want to know what happens if there is too much yeast in bread?
Is this you? If so, I’ll give you some quick answers to what happens and also some guidance so you know what to do if you add too much yeast to a bread dough.
What does yeast do to the bread?
Yeast is found in sourdough starters or in bakers yeast and has a few core roles to play in bread making. It reacts with the starches that are presented by the flour to create:
- Carbon dioxide
- Lactic acid
- Organic acids
We most associate yeast with creating carbon dioxide gas. This is what gets locked in the breads crumb structure and makes the bread rise. The formation of ethanol, lactic acid and organic acids are just as vital to the process as they mature the dough.
How does dough maturation work?
The gluten strands formed from hydrated flour are not strong enough to retain gas on their own. To support the structure of the dough, the yeast converts some of the starch into natural dough conditioners.
The development of ethanol, lactic acid, organic acid and natural enzymes supports the gluten to be able to transform flour, water, salt and yeast into bread.
The conditioners support the doughs gas retaining properties, the elasticity and extensibility of the dough, as well as the keeping quality, aroma and the flavour of the bread.
A well fermented dough that has been made over a long period of time will be matured so that it contains a high amount of natural dough conditioners
What happens if you use too much yeast?
When too much yeast is added to the dough, the activity of gas and ethanol increase rapidly to create a gassy dough that's hard to work with! Due to the high gas activity we are forced to reduce the mixing time and get the loaves baked quickly before they over-proof.
Dough which has a short fermentation period does not mature fully, leading to several quality issues once baked.
What happens to bread when too much yeast is added?
When proofing is rushed, the following faults can occur in the bread:
- Irregular holes through the bread crumb
- Ripped or ruptured crust
- Pale coloured bread
- Bread collapses when cutting or in the oven
- Taste and smell of bread flavours will decrease
- The bread smells and tastes of yeast
- The bread smells and tastes of alcohol
- Massive oven spring which results in the bread getting stuck in the oven
- The dough gets overly gassy so kneading time is reduced which lowers the quality of the bread
How much yeast is too much?
Most standard bread recipes use 1.5-2% yeast in the recipe with the most common being 2% for everyday breads. The percentage used for the recipe is based on the bakers percentage for the bread made. This is where the percentage of each ingredient is derived from the total amount of flour used in the recipe.
If the percentage of yeast used is above 2.2% of the flour, the bread will start to taste and smell of yeast and is likely to suffer from the other common issues shown above.
Fresh, active dried and instant yeast conversion
The standard 2% yeast to flour ratio used in many bread recipes is based on using fresh yeast. If using instant yeast or active dried yeast we need to convert the recipe to determine how much to use. We can convert roughly by halving the fresh yeast to get the value for active dried yeast or dividing the fresh yeast value by 3 to get the measurement for instant yeast.
For accurate conversions, use these percentages to convert fresh yeast to active dried or instant yeast:
Where fresh yeast is 100%
Active dried yeast is 42%
Instant yeast is 33%
What to do if you add too much yeast to bread
The best thing to do if you have added too much yeast to the bread is to lower the temperature of the dough for the bulk fermentation. Cool temperatures slow down the production of gas whilst still allowing the dough to continure to mature. If this can’t be done, there are a few other tips for working with over-yeasted dough:
- Midway through mixing, place the dough in the fridge to cool for ten minutes before mixing again
- Prepare for a big oven spring by under proofing the bread slightly
- Increase the salt to 2.2% of the flour used in the recipe. Salt helps to control the yeast.
- Trade white flour for whole-grain flour if possible, it will slow down the rate that the starch breaks down into sugars
- Don’t cut the bread before baking if it has had a quick rise
- Place in the fridge and use as a pâte fermentée in the following day’s dough
The breads smell & taste change when too much yeast is added
If we make changes to the control the yeast such as cooling the dough down there is one issue that cannot be reversed. If the yeast is added at levels higher than 2.5% the bread will smell and taste less like bread and more like yeast. There is no way to reverse this.
Ending thoughts on using too much yeast
It’s a pain when you realise you have added too much yeast. The best thing we can do is to cool it down as soon as possible.
I have found that I have to calculate and write down the recipe before I start baking, otherwise accidents happen regularly!