Yeast, a microorganism that converts sugar into carbon dioxide and alcohol, is an essential ingredient in the manufacture of pasta of all kinds and beers. The yeast is usually activated to check that it is alive and to make it work more quickly. Modern yeast packing techniques have made this step less useful, but you could still activate a yeast that you've left in the cupboard for too long.
Method 1 of 2: Activate dry yeast
Step 1. Skip this step if you are using instant yeast
Instant Yeast or Quick Setting Yeast does not need to be activated and you can add it directly to your dry ingredients. It is permanently active and has a very long lifespan. Some professional bakers will tell you that instant or active yeast gives a bad taste that fresh yeast doesn't, while others don't feel any difference in the finished product.
- Do not use never yeast for beer, champagne or wine when baking cakes.
Step 2. Measure out a small amount of water or milk
Pour a small amount of water or milk into a heat-resistant container, marking the amount you just poured on it. You can add a little more liquid, but you have to deduct it from the rest of the ingredients in the recipe. 120ml should be more than enough for any bread recipe.
For example, if you are using 120ml of water to activate your yeast and your recipe calls for 240ml of water, use 120ml later in the recipe instead of the 240ml since you will already have 120ml of water you will have mixed with the yeast
Step 3. Heat the liquid
Heat the liquid to around 40 degrees C, which is hot enough without being hot and without steaming. Although yeast can activate at lower temperatures, dry yeast needs warmer temperatures to start.
If you don't have a food thermometer, heat the liquid until it becomes lukewarm. The yeast will take longer to activate if the liquid is too cold, but too hot liquid could kill the yeast and then it will not activate at all
Step 4. Mix a teaspoon (5 ml) of sugar
It only takes hot water to activate the yeast, but the sugar will let you know if the yeast is ready. The active yeast will consume the sugar and produce carbon dioxide and other substances, it is exactly this process that allows the dough of the bread to rise and gives it its unique taste. Quickly stir the sugar until it dissolves.
If you forget to add sugar, you can add it again after the yeast is in the water. This will work just as well, but you need to stir more gently to avoid spilling the liquid or damaging the yeast
Step 5. Sprinkle the yeast over the liquid
Measure out the amount of yeast needed for your recipe and sprinkle it over the liquid. If the recipe you are following instructs you to use fresh yeast, the amount of dry yeast will be half the amount of fresh yeast, since the dry yeast is more concentrated. If the recipe calls for instant yeast, multiply that amount by 1.25 to find the amount of dry yeast you need.
Please note that some types of yeast swell in water. Pour the water into a larger container if necessary to avoid overflowing the liquid
Step 6. Stir the yeast again after 30 to 90 seconds
As the yeast on the surface falls into the liquid, the water will dissolve the coating of the inactive yeast and release the yeast in the middle. After giving it a little time, gently mix the yeast into the water.
It is not necessary to time this step. You are unlikely to change anything by stirring the yeast, even if you stir it right after putting it on
Step 7. Wait ten minutes for bubbles or scum to form
If the yeast is active and alive, it will start consuming the sugar and releasing carbon dioxide, the gas that swells the bread. If the surface of the mixture starts to bubble or froth, it means your yeast is active and can be added to the other ingredients in the recipe.
- Look closely at the edges of the container to see bubbles forming.
- You may also know that the yeast is active if you notice a yeast odor or a greater volume of liquid, but these two clues are not always identifiable.
- Unfortunately, if the mixture doesn't bubble, it's likely the yeast is dead and you can't use it in your recipes. Try adding water that is slightly warmer, but not hotter than 43 degrees C, and let sit for another 10 minutes. If the yeast still hasn't bubbled, throw it away.
Step 8. Add the liquid yeast mixture to the recipe you are following
Add the liquid that contains the yeast to the recipe when the recipe gives you to add the yeast. Do not try to collect the yeast by passing it through a colander.
Method 2 of 2: Activate fresh yeast
Step 1. Think about the problems with fresh yeast
Fresh yeast is yeast that has been stored in a slightly damp package that keeps it active, but cannot keep it as long as the dry yeast technique does. Be aware that fresh yeast is unlikely to survive in the freezer and will only survive one to two weeks at room temperature and one to three months in the refrigerator. If the yeast has turned hard or brown, it is best not to use it. You can still test it by trying to activate it, but it will be wiser to buy another packet of fresh yeast in case it is dead.
- Note: we also speak of fresh yeast as baking yeast, wet yeast or compressed yeast.
- Do not replace never fresh yeast with brewer's yeast. Use only baker's yeast (in any form) to make cakes and bread.
Step 2. Pour a small amount of water or milk into a heat-resistant container
Measure out 60 ml of liquid which you will also use in your recipe. You can use a little more yeast if needed, but be sure to write down how much liquid you use to deduct it from the rest of the ingredients in the recipe.
For example, if you use 240ml of milk in your recipe and if you use 60ml of milk to activate the yeast, use 180ml of milk later in the recipe by adding the 60ml of yeast
Step 3. Heat the liquid
Heat the liquid to between 27 and 32 degrees C, the perfect temperature to encourage yeast development. Fresh yeast is already active and has not been inhibited like dry yeast, so it is not necessary to use a liquid that is too hot to wake it up.
- It's a lukewarm temperature. If you see steam or a film forming on the surface of the milk, it means it's too hot and you've killed the yeast.
- Since fresh yeast already contains moisture, you technically don't need to add water. It is advisable in most cases to add water, since the room temperature may not be hot enough to activate the yeast. However, if it is hot enough in the room, you can simply mash sugar and yeast together.
Step 4. Mix 1 teaspoon (5 ml) of sugar
Yeast feeds on any type of sugar, so mix in a small amount of white, brown, or other natural and sweet sugar. Do not use sweeteners to activate your yeast.
Step 5. Add the yeast to the liquid
Stir gently, adding the amount of yeast required by the recipe. Since fresh yeast already contains liquid in addition to the yeast, you will need to adjust the amounts if the recipe calls for another type of yeast.
- If the recipe calls for dry yeast, multiply the amount requested by two to find the amount of fresh yeast needed.
- If the recipe calls for instant yeast, multiply the amount requested by 2.5 to find the amount of fresh yeast needed.
Step 6. Wait a few minutes and watch for bubbles
If you observe any bubbles or scum after 5-10 minutes it means your yeast is active and alive, you can now add it to your recipe. If not, chances are the liquid has been too hot or too cold, the yeast must be dead and you can throw it away.
Since fresh yeast is kept active, it will take less time to bubble than dry yeast
- If you are making a dough, you can activate the yeast in the same container where you prepare the dry ingredients. Make a well with the flour and use it as if it were a bowl.
- When it comes to sugar, any food that contains chemical sugar (saccarose, fructose, etc.) and very little, if at all, acid will do: brown sugar, sugar. white, molasses or fruit juices. The yeast will not take if you use sweeteners.
- While the yeast activates, it will exhale a smell of bread. This is completely normal.
- If you have little time to prepare your recipe and the yeast you have has not been purchased recently, you should activate some yeast in a bowl before starting the recipe. If the yeast does not activate, you will have time to go to the supermarket to buy another packet.
- Light can kill yeast. This is why most bread recipes require you to cover the bowl when you rest the dough.
- Do not put yeast in water that is ice cold or that is too hot to touch. This could kill the yeast or at least prevent it from activating.
- Temperatures below 10 degrees C will deactivate the yeast and temperatures above 50 degrees C will kill it.
- Salt can slow the activity of yeast and even kill it in high concentrations. Add the salt to the other dry ingredients and not to the bowl where you activate the yeast, even if the recipe tells you to do the opposite.