Types of yeast

Imagine a fresh, aromatic hot loaf of bread, just taken out of the oven. Bread is risen, with a crackly surface and soft airy inside. It’s bouncy when you press it with your fingers and beautifly chewy when you take a bite. We all love the warm delicacy of freshly baked bread, pizza or any kind of baked goods, but did you ever think about the ingredients that provide results we all enjoy that much?

Yeast is one of main ingredients of bread and many other baked goods. Baker’s yeast is a common name for different kinds of yeast used as a leavening agent while making dough. Yeast is the one to “blame” for the rise of the dough, but yeast does more than that – it develops flavour and gives texture to baked goods.

Interesting fact – yeast is not exclusive just for the baking industry – it’s also used in beer and wine production!

Today we are talking all about yeast.

What is yeast? 

Bread yeast is a kind of fungi, a microorganism with a single cell. As a fungi it belongs to the same family as mushrooms and molds, such as mold in a blue cheese or mold in pharmaceutical goods. Yeast species used in the baking industry are known as Saccharomyces cerevisiae. Yeast manufacturers use different kinds of processes to produce yeast, but usually they save strains from previous batches to make new ones.

Yeast is special because of its ability to grow faster than any other living thing. Fungi in yeast need a special environment – warm temperature, humidity and of course oxigen, and also adequate food for growth – sugar and liquid. 

You’re wondering how yeast actually works? Yeast triggers the process of fermentation. No fermentation – no bread. Yeast, as a leavening agent, produces gases that make dough rise. It consumes sugars in flour and expels carbon dioxide in this process. Gas is “trapped” inside the dough and cannot escape, because the dough is elastic and stretchable, so it spreads all over the dough in the form of a thousand small bubbles. That’s the texture you see when you cut open the loaf of bread.

Interesting fact: Yeast works similarly in the beer, too. It eats sugars and produces carbon dioxide and alcohol, which gives recognizable taste to one of the most popular beverages in the world.

What is yeast made of?

Yeast is single-celled fungi, which has a shape of egg, so miniature that is visible only with a microscope. Did you know that it takes 20 billion of these cells to create one gram of yeast? That’s how small they are, but yet, their strength is enormous. 

Is yeast good or bad?

Consuming yeast can be good for your body, as long as you don’t have a yeast allergy. If you’re allergic to yeast, you won’t be able to eat any kind of yeast bread or baked goods, without the allergic reaction. Even if you’re not allergic you shouldn’t eat active dry yeast directly – it can be very dangerous and trigger massive immune responses. Symptoms of yeast poisoning include cramps, bloating, constipation and diarrhea. It also increases the risk of fungal infections, especially in people who already have health issues.

Yeast in food and yeast supplements can have benefits for healthy adults. It contains a B-complex vitamins – B1 (thiamine), B2 (riboflavin), B3 (niacin), B5 (pantothenic acid), B6 (pyridoxine), B7 (biotin) and B9 (folic acid). B-complex vitamins are important for the nervous system, your skin, hair and nails and much more.

Is yeast natural?

Yeast is natural. This fungi made of single cells is considered to be the first domesticated living creature in history. Yeast is everywhere around you – in the air you breathe, on the trees, ground, fruits, such as grapes and berries (In history berries were used as a natural start for yeast bread).

Is yeast suitable for vegetarians?

Yes, yeast is suitable for vegan and vegetarian diets. Yeast is a living organism, even though it has only one cell. Many vegans and vegetarians are wondering if it is suitable to add yeast to their diet which doesn’t contain any animal products. 

Yeast, unlike animals, doesn’t have a nervous system – it cannot feel the pain, so using yeast doesn’t include any kind of cruelty. Furthermore, yeast is recommended food in vegan and vegetarian diets – they often lack vitamin B and yeast is filled with B-complex vitamins.

Four types of yeast for baking?

Did you ever wonder why your bread is not turning the way you expected? Maybe you’ve been using the wrong kind of yeast! There are 4 most common types of yeast for baking:

Active dry yeast 

Active dry yeast is the type of yeast you usually see on store shelves. This type is best for bread making and most bread recipes are calling for active dry yeast, unless otherwise is specified. Active dry yeast looks like little beige granules – like poppy seeds, which activates combined with liquid – usually water (or milk). Active dry yeast requires proofing. You’ll prove it by mixing it with one teaspoon of sugar and ¼ cup lukewarm water. You can even add a bit of honey, to escalate the proofing process. Yeast will in 5 to 10 minutes become bubbly and that’s the time when you can use it as the recipe demands. This type of yeast is the best one to go with if you’re using the bread making machine.

Fresh yeast

Fresh yeast is often ignored by amateur bakers, although chefs love it! It develops fast, it’s easy to use and it gives special flavour to bread. Fresh yeast is packed as small blocks, wrapped in paper or alu-foil. Using fresh yeast is a bit different than using active dry yeast. It’s compact so you’ll have to crumble it first. Mix it with warm liquid and sugar and wait a bit to start to bubble, or add it to other ingredients and knead the dough. Fresh yeast activates faster than the dry one and stays active longer. Make sure the recipe calls for fresh yeast!

Instant yeast

Instant yeast is similar to active dry yeast, only it’s dried faster. Instant yeast is more delicate and fine than active dry yeast, so it acts faster. It’s also in the form of granules, just really tiny fine ones. Using instant yeast doesn’t require water or any other kind of liquid. You can add it right away to other dry ingredients, without proofing. We recommend you to use instant yeast when you’re kneading the dough by hand or with bread machine. Instant yeast is also called rapid-rise or quick-rise yeast.

Rapid dry yeast

Last but not least, rapid dry yeast resembles a lot to instant yeast. They look the same, but rapid dry yeast has some enzymes added, so it acts even faster. You won’t need to prove it. Enzymes will begin the fermentation process when rapid dry yeast is combined with dry ingredients. Rapid dry yeast is a great solution when you need to make a loaf of bread as soon as possible. You wont need to wait for the dough to rise – you can bake it immediately. 

Tip: The best way to learn which kind of yeast is ideal for your recipes is to experiment and play with all kinds. You have nothing to lose, your bread can be only better. Still, if the recipe you follow calls against some kind of yeast you shouldn’t force it.

What is the difference between active dry and instant yeast?

Active dry and instant yeast have a lot of things in common. They both act very quickly, making wonderful loafs of soft and airy bread. They have their differences too:

  • Active dry yeast has the form of granules, while instant yeast is finely milled powder.
  • Instant yeast has more live cells than active dry yeast.
  • Active dry yeast is a bit slower than instant yeast.
  • Active dry yeast requires water for the proofing process. You don’t need to proof instant yeast. You can simply add it to the other dry ingredients.
  • Active dry yeast is suitable for bread making machines, while instant yeast gives the best results when kneading by hand.

What are osmotolerant and nutritional yeast?

Osmotolerant yeast is the kind you use for really sweet sugary doughs, such as cinnamon rolls. Sugary dough often takes a lot of time to rise, so they require a special kind of yeast which will create a light and airy texture of the dough. Osmotolerant yeast can be difficult to find in grocery stores, but you can always purchase it online. It is also a bit more expensive than the other types of yeast.

Nutritional yeast is not meant for baking. That’s deactivated yeast that serves as a natural supplement, cause it’s high in vitamin B. As we said – you cannot use nutritional yeast for baking and that goes the other way around – you shouldn’t eat active yeasts instead of nutritional.

Which yeast is best for baking?

Depending on your recipe all kinds of yeast could potentially be a great way to go! Most popular choices are active dry and instant yeast. 

They are easy to use – they both come in small bags, have the form of granules and make that wonderful rise we all love. If you decide to use instant yeast, you’ll save yourself a bit of time – it doesn’t need to be proof. You can use it immediately. 

Active dry and instant yeast are so similar that you can replace one with another in a recipe. Make sure just not to put instant yeast into the bread making machine. 

Can I make yeast at home?

Yes, you can! Covid-19 pandemic caused a shortage of yeast on the market, because many people started to make their own bread. Homemade bread is usually healthier than the store-bought and kneading is a great way to keep yourself busy. If yeast shortage was the case in your neighbourhood too, don’t worry, there are three ways to make yeast at home:

  • Using fresh or dried fruit
  • Using potato water
  • Using flour or bread leftovers

Tip: When you make yeast from ingredients we mentioned above, it’s called a starter. Keep your starter at room temperature and feed it daily with water and flour. If you put your starter in the refrigerator you can feed it once a week.

How do I make homemade yeast  – sourdough starter?

You’ll need seven days to make sourdough starter from scratch – but you may need to wait a few additional days to bake with it. That depends on the temperature and humidity in your home. Generally speaking, a more mature starter is – better rise will your bread loaf achieve.

Ingredients:

  • 50 grams flour bread (all-purpose)
  • 50 grams filtered water

Instructions:

Day 1 – Mix 50 grams flour bread and 50 grams filtered water in a clean jar. Place the lid loosely and put the jarm in a warm place for the next 24 hours.

Day 2 – Check on your starter and give it a good stir, so the oxygen enters the mixture. You may notice a few bubbles forming, but if there are no bubbles, that’s fine. Time will do it’s own thing. Leave the jar in a warm place for the next 24 hours.

Day 3 – Remove half of your starter from the jar and add 50 grams flour and 50 grams water to remains of the starter. Mix it well with a wooden spoon and leave until the next day.

Day 4 – Again remove half of your starter and feed it – add 50 grams of flour and 50 grams of water. Mix all together with a wooden spoon and repeat the process after 12 hours.

Day 5 – Repeat the same as you did yesterday. Remove 100 grams from your starter mixture and feed it again. Place the lid loosely and leave it in a warm place. Again – feed it every 12 hours.

Day 6 – Same procedure as in day 3, 4 and 5. Feed your starter and put back the lid. 12 hours feeding regime still goes on.

Day 7 – Your starter is ready, but for best results keep feeding it twice a day for 14 days. That way your starter will be mature enough and it will make a nice, juicy loaf of bread.

Tip: When you remove half of a starter on day 3, you can put it in a clean jar and create a new starter using the same method we described.

What is necessary for yeast to grow?

Yeast requires 4 factors for growth – moisture, warmth, food and nutrients. 

Yeast will need a source of food – sugar, to be precise, and also warm water or milk. Yeast’s growth is affected by the environment, too – temperature and humidity. Oxygen is also required for the yeast growth. Without oxygen, the fermentation process won’t be successful. 

Is there a replacement for yeast?

Yes, there are three replacements for yeast! They won’t get you exactly the same results as yeast – they are not replicas, but they are the best substitutes which will accelerate the rising process if you don’t have yeast on your hands. They will add airiness, lightness and chewiness to baked goods.

Baking powder

Baking powder is a leavening agent made of baking soda and acid, usually cream of tartar. It reacts in two different ways – when it’s mixed with warm water or when it’s exposed to heat. In both cases gas bubbles will create, expand and make the dough rise. You can replace the same amount of yeast with an equal amount of baking powder.

Baking soda and acid

Combining baking soda and acid will create the same reaction as baking powder. You can mix baking soda with lemon juice, buttermilk, cream of tartar or milk and vinegar (mixed in 1:1 ratio). If used separately baking soda and acid will give no results at all. You must mix them. Replace half of yeast recipe calls for with baking soda and the other half with acid. For example – if the recipe calls for two spoons of yeast, use one spoon of baking soda and one spoon of acid. Mix them well and add to other ingredients.

Sourdough starter

Sourdough starter is naturally grown yeast. It is made out of flour and water and it is used for making sourdough bread. Sourdough starter will be ready to use in 7 days (for best results leave it 14 days, to be completely mature), although some starters are kept for years to provide strong flavour and chewy texture of artisan breads. You can use 300 grams (1 cup) of sourdough starter to replace a 2-spoon package of yeast. 

Tip: If your sourdough starter is contaminated in any way – if it changes color, develops mold or has unpleasant smell – do not use it for making bread.