How to Pitch Yeast for Home Brew Beer

Learn how to pitch yeast into home brew beer wort. Discover the differences between liquid and dry yeast, and best practices for a perfect fermentation.

HOW-TO

Mat Stuckey

9/2/202315 min read

Pitching yeast is a crucial step in the brewing process, as it can significantly affect the flavour, aroma, and quality of your beer.

This article will explore the best practices for pitching yeast correctly into your beer wort, including the different types of yeast, the importance of pitching temperature, and how much yeast to pitch.

Understanding these elements is essential for any home brewer looking to perfect their craft and brew delicious beer.

Understanding Yeast

Yeast is a crucial component in the brewing process as it is responsible for fermentation.

Fermentation is the process where yeast converts the sugars present in the wort into alcohol and carbon dioxide, which is fundamental for the beer's alcohol content and carbonation.

There are hundreds of yeast strains available, each with its unique characteristics that can influence the beer's flavour, aroma, and clarity.

However, they all fall into two main categories: ale yeast (Saccharomyces cerevisiae) and lager yeast (Saccharomyces pastorianus).

Ale yeast is top-fermenting, meaning it ferments at the top of the fermenter and is typically used in brewing ales, stouts, and IPAs. It ferments at warmer temperatures, usually between 15-25°C (59-77°F), and produces fruity and spicy flavours.

Lager yeast, on the other hand, is bottom-fermenting, meaning it ferments at the bottom of the fermenter.

It is typically used in brewing lagers and pilsners and ferments at cooler temperatures, usually between 7-13°C (45-55°F), producing cleaner, crisper flavours with fewer fruity esters.

Therefore, selecting the right yeast strain is crucial for achieving the desired characteristics of your beer.

Key Points:

  • Yeast is a single-celled organism responsible for fermenting the sugars in the wort into alcohol and carbon dioxide.

  • There are two main types of yeast used in brewing: ale yeast (Saccharomyces cerevisiae) and lager yeast (Saccharomyces pastorianus).

The yeast strain you choose will affect the flavour, aroma, and clarity of your beer.

Dry Yeast vs. Liquid Yeast

Both dry and liquid yeast have their advantages and disadvantages, and the choice between the two often depends on the brewer's preference, experience, and the specific beer style being brewed.

Dry Yeast: Dry yeast is yeast that has been dehydrated and turned into a powder. It is easy to handle, has a longer shelf life (up to two years if stored properly), and is usually less expensive than liquid yeast.

Dry yeast also does not require refrigeration, making it easier to store and ship. However, the downside is that there is a smaller variety of dry yeast strains available compared to liquid yeast, and some brewers argue that liquid yeast produces a more authentic and complex flavour.

Nevertheless, the quality of dry yeast has improved significantly over the years, and many brewers successfully use dry yeast to produce excellent beers.

Liquid Yeast: Liquid yeast comes in a liquid suspension and offers a much wider variety of strains, allowing for more creativity and the ability to match specific beer styles.

It usually provides a more vigorous fermentation and, as some brewers believe, a more authentic and complex flavour profile. However, liquid yeast has a shorter shelf life (usually 4-6 months), is more expensive, and requires refrigeration.

Additionally, liquid yeast often requires making a yeast starter to ensure a healthy yeast population and a strong fermentation, especially for high gravity beers.

Key Points:

  • Dry yeast is dehydrated yeast that is easy to handle, has a longer shelf life, and is usually less expensive than liquid yeast. However, there is a smaller variety of dry yeast strains available.

  • Liquid yeast comes in a liquid suspension and offers a wider variety of strains, allowing for more creativity and the ability to match specific beer styles. However, it has a shorter shelf life, is more expensive, and usually requires making a yeast starter.

How Much Yeast to Pitch

The amount of yeast you need to pitch depends on several factors, including the gravity of your wort, the fermentation temperature, and the yeast strain. A general guideline is to pitch 0.75-1.0 million yeast cells per millilitre of wort per degree Plato.

However, higher gravity worts and lower fermentation temperatures may require higher pitching rates.

It's essential to calculate the right amount of yeast for your brew, as underpitching can lead to incomplete fermentation, off-flavours, and other problems, while overpitching can lead to a lack of ester production and a too clean beer.

Rehydrating Dry Yeast

Dry yeast needs to be rehydrated before pitching into the wort. To rehydrate dry yeast, sprinkle the yeast into warm water (30-35°C or 86-95°F) and let it sit for about 15-30 minutes. Stir gently to ensure all the yeast is hydrated.

It's essential to rehydrate the yeast in water, not wort, as the high sugar concentration in the wort can cause osmotic shock and kill the yeast cells.

After rehydrating, the yeast should be pitched into the wort as soon as possible. When you hydrate the dry yeast in water before pitching, you are ensuring the yeast cells are fully awakened from their dormant state and are ready to start fermenting the sugars in the wort.

Rehydrating the yeast in water before pitching can lead to a more vigorous and healthy fermentation. It’s also good practice to rehydrate the yeast at a temperature close to the temperature of the wort, to avoid shocking the yeast with a sudden temperature change.

If the yeast is not rehydrated, it may take longer to start fermenting, and there is a risk that some of the yeast cells will die, leading to a weaker fermentation and possibly off-flavours in the beer.

  • Dry yeast should be rehydrated in water, not wort.

  • Rehydrating the yeast helps awaken the yeast cells from their dormant state.

The yeast should be rehydrated at a temperature close to the temperature of the wort.

Making a Yeast Starter for Beer

A yeast starter is a small volume of wort that is fermented before pitching into the full batch of wort. Making a yeast starter is especially important for liquid yeast, as it ensures a healthy yeast population and a strong fermentation.

To make a yeast starter, boil a small amount of dry malt extract in water, cool it down, and then add your yeast. Let it ferment at room temperature for 24-48 hours, and then it’s ready to pitch into your wort.

Making a yeast starter is a good way to ensure that you have a sufficient amount of healthy yeast to ferment your beer.

The yeast starter will multiply the yeast cells and get them active and ready for fermentation.

A yeast starter also allows the yeast to consume any oxygen in the starter wort, which can help prevent oxidation of the beer.

It’s important to note that the yeast starter should be well-aerated to encourage yeast growth, but the main batch of wort should not be aerated after the yeast is pitched.

  • Making a yeast starter is important for liquid yeast.

  • A yeast starter ensures a healthy yeast population and strong fermentation.

  • The starter wort should be well-aerated, but the main batch of wort should not be aerated after pitching the yeast.

Pitching Temperature

The pitching temperature is the temperature of the wort when you add the yeast. It's essential to pitch the yeast at the right temperature to ensure a healthy fermentation. The pitching temperature should be within the fermentation temperature range of the yeast strain you are using.

For ale yeast, this is usually 18-22°C (64-72°F), and for lager yeast, it is 7-13°C (45-55°F).

It's important to cool the wort down to the pitching temperature as quickly as possible after boiling to minimise the risk of infection.

The pitching temperature is crucial because yeast is sensitive to temperature changes, and pitching the yeast at the wrong temperature can cause off-flavours or even kill the yeast.

For example, pitching yeast at too high a temperature can cause the yeast to produce more fusel alcohols, which have a harsh, solvent-like taste.

On the other hand, pitching yeast at too low a temperature can cause the yeast to become dormant and not ferment the wort.

It’s important to use a thermometer to accurately measure the temperature of the wort before pitching the yeast.

  • The pitching temperature should be within the fermentation temperature range of the yeast strain.

  • Pitching yeast at the wrong temperature can cause off-flavours or kill the yeast.

  • Use a thermometer to accurately measure the temperature of the wort before pitching the yeast.

Time to Pitch the Yeast

One crucial aspect of brewing that often gets overlooked is the timing of pitching the yeast. The time to pitch the yeast is when the wort has cooled down to the appropriate temperature for the yeast strain being used.

This is typically between 15-25°C (59-77°F) for ale yeast and 7-13°C (45-55°F) for lager yeast.

However, it is essential to check the manufacturer's recommendations as some yeast strains may have different optimal temperatures.

It is also important to consider the yeast's health and viability. If you are using liquid yeast or a yeast slurry, it is recommended to make a yeast starter ahead of pitching to ensure the yeast is healthy and active.

If you are using dry yeast, it is essential to rehydrate the yeast in water before pitching.

  • Check the manufacturer's recommendations for the optimal pitching temperature of your yeast strain.

  • Make a yeast starter for liquid yeast or yeast slurry ahead of pitching.

  • Rehydrate dry yeast in water before pitching.

Yeast Health

The health and viability of the yeast are also essential for successful fermentation. It is recommended to make a yeast starter for liquid yeast or yeast slurry ahead of pitching to ensure the yeast is healthy and active.

A yeast starter is a small volume of wort that is inoculated with yeast and allowed to ferment for 24-48 hours before pitching into the main batch of wort.

Dry yeast should be rehydrated in water before pitching. Sprinkling dry yeast directly into the wort can lead to a significant loss of viability.

To rehydrate dry yeast, sprinkle the yeast into warm water (35-40°C or 95-104°F) and let it sit for 15-30 minutes before adding to the wort.

white and black heart shaped chocolate
white and black heart shaped chocolate

Best Practices for Pitching Yeast

  1. Calculate the Pitching Rate: Use a yeast calculator to calculate the correct pitching rate for your beer.

  2. Prepare the Yeast: Make a yeast starter for liquid yeast or rehydrate dry yeast in water before pitching.

  3. Cool the Wort: Cool the wort down to the appropriate pitching temperature before adding the yeast.

  4. Aerate the Wort: Aerate the wort by shaking the fermenter or using an aeration stone before pitching the yeast.

  5. Add the Yeast: Gently pour the yeast into the fermenter and seal the fermenter with an airlock.

  6. Monitor the Fermentation: Depending on yeast strain, monitor the fermentation by taking hydrometer readings and checking for signs of fermentation such as krausen formation, bubbles in the airlock, and fermentation aroma.

Taking Hydrometer Readings

Taking hydrometer readings is essential to monitor the progress of fermentation and determine the beer's alcohol content.

A hydrometer measures the density of a liquid relative to water. As fermentation progresses, the sugar in the wort is converted into alcohol and carbon dioxide, which decreases the density of the liquid.

It is essential to take a hydrometer reading before pitching the yeast, known as the original gravity (OG), and at the end of fermentation, known as the final gravity (FG). The difference between the OG and FG can be used to calculate the alcohol content of the beer.

It is also recommended to take hydrometer readings at regular intervals during fermentation to monitor the progress and ensure it is proceeding as expected.

If the fermentation seems to be stuck or not progressing as expected, it may be necessary to take corrective actions, such as raising the temperature, adding more yeast, or adding yeast nutrient.

  • Take a hydrometer reading before pitching the yeast (OG) and at the end of fermentation (FG).

  • Take hydrometer readings at regular intervals during fermentation to monitor progress.

  • Take corrective actions if necessary.

Adding Yeast to the Wort

After rehydrating the dry yeast or making a yeast starter for liquid yeast, it's time to add the yeast to the wort.

Gently pour the yeast into the fermenter.

Then, aerate the wort by shaking the fermenter or using an aeration stone. Aeration is essential as it provides the oxygen necessary for yeast growth and healthy fermentation.

After adding the yeast and aerating the wort, seal the fermenter and attach the airlock.

  • Rehydrate dry yeast or make a yeast starter for liquid yeast.

  • Gently pour the yeast into the fermenter.

  • Aerate the wort.

  • Seal the fermenter and attach the airlock.

Yeast Pitching Rate

The pitching rate is the amount of yeast added to the wort, usually expressed as the number of yeast cells per millilitre of wort.

The correct pitching rate depends on the gravity of the wort and the type of beer being brewed. Higher gravity worts and lagers typically require higher pitching rates than lower gravity worts and ales.

A general guideline is to pitch about 0.75-1 million cells per millilitre of wort per degree Plato for ales, and 1-1.5 million cells per millilitre of wort per degree Plato for lagers.

It is important to calculate the pitching rate using a yeast calculator to ensure you are pitching enough yeast. Under-pitching can lead to incomplete fermentation, off-flavours, and increased risk of contamination.

Over-pitching can lead to over-attenuation, off-flavours, and a waste of yeast.

Aerating the Wort

Aerating the wort is an essential step in the brewing process.

Yeast needs oxygen for cell growth and to reproduce to a healthy population size.

However, once fermentation starts, oxygen is the enemy as it can lead to off-flavours and spoilage.

Therefore, it's essential to aerate the wort before pitching the yeast, and then seal the fermenter to prevent any oxygen exposure during fermentation.

  • Aerating the wort is essential for yeast cell growth and reproduction.

  • Oxygen is the enemy once fermentation starts.

  • Aerate the wort before pitching the yeast.

  • Seal the fermenter to prevent oxygen exposure during fermentation.

Signs of Healthy Fermentation

Healthy fermentation is essential for producing high-quality beer.

Signs of healthy fermentation include a thick, creamy krausen forming on top of the wort, bubbles in the airlock, and a pleasant fermentation aroma.

It usually takes 12-36 hours for fermentation to start, so don't panic if you don't see any signs of fermentation immediately after pitching the yeast.

  • Signs of healthy fermentation include thick, creamy krausen, bubbles in the airlock, and a pleasant aroma.

  • Fermentation usually starts 12-36 hours after pitching the yeast.

Don't panic if there are no signs of fermentation immediately after pitching.

a close up of a glass of beer with drops of water
a close up of a glass of beer with drops of water

How to Pitch Yeast: Common Mistakes and How to Avoid Them

Some common mistakes when pitching yeast include not rehydrating dry yeast, not making a yeast starter for liquid yeast, pitching the yeast at the wrong temperature, and not aerating the wort properly.

  • Not rehydrating dry yeast: Dry yeast needs to be rehydrated in water before pitching. Simply adding dry yeast directly to the wort can lead to a longer lag time before fermentation starts and may result in incomplete fermentation.

  • Not making a yeast starter for liquid yeast: Liquid yeast usually contains fewer cells than needed for high gravity worts or larger batches. Making a yeast starter helps to increase the yeast cell count and ensures a healthy fermentation.

  • Pitching the yeast at the wrong temperature: Yeast is sensitive to temperature, and pitching at the wrong temperature can stress the yeast and lead to off-flavours. It is essential to cool the wort to the appropriate temperature for your yeast strain before pitching.

  • Not aerating the wort properly: Yeast needs oxygen for cell growth and reproduction. Inadequate aeration can lead to a slow or stuck fermentation.

To avoid these mistakes, follow the best practices outlined in this article and always carefully read and follow the instructions that come with your yeast.

  • Rehydrate dry yeast in water before pitching.

  • Make a yeast starter for liquid yeast.

  • Cool the wort to the appropriate temperature before pitching the yeast.

  • Aerate the wort properly.

Fermentation Chambers and Vessels

The fermentation chamber or vessel is a crucial component in the brewing process.

This is where the wort, with the pitched yeast, will ferment and transform into beer.

The fermenter needs to be sanitised properly before adding the yeast and the wort to prevent any contamination.

Types of Fermentation Vessels

There are several types of fermentation vessels available for homebrewers and professional brewers alike:

  1. Glass Carboys: These are traditional fermentation vessels that are durable and impermeable to oxygen. However, they are heavy and can be fragile.

  2. Plastic Buckets: These are the most common for homebrewers because they are inexpensive, lightweight, and easy to clean. However, they can scratch easily, which can harbour bacteria.

  3. Stainless Steel Fermenters: These are preferred by professional brewers because they are durable, easy to clean, and impermeable to oxygen. However, they can be expensive for homebrewers.

  4. Conical Fermenters: These are specially designed fermenters that allow for easier removal of sediment and yeast at the end of fermentation. They can be made of plastic or stainless steel.

Importance of Temperature Control When Pitching Yeast

The fermentation chamber needs to maintain a consistent temperature suitable for the yeast strain being used.

The fermentation temperature will affect the yeast activity, and consequently, the flavour, aroma, and clarity of the beer.

Ale yeast typically ferments at warmer temperatures (15-25°C or 59-77°F), while lager yeast ferments at cooler temperatures (7-13°C or 45-55°F).

It is crucial to have a fermentation chamber that can maintain a consistent temperature throughout the fermentation process. Some brewers use a temperature-controlled refrigerator or freezer as a fermentation chamber.

Sealing and Aeration

Once the wort and yeast are added to the fermentation vessel, it needs to be sealed properly to prevent contamination and oxygen exposure. An airlock is usually attached to the fermenter to allow carbon dioxide to escape while preventing anything from getting in.

Before sealing the fermenter, it is essential to aerate the wort. Aeration is necessary to provide oxygen for yeast growth and healthy fermentation.

However, once fermentation starts, oxygen exposure should be minimised to prevent off-flavours and spoilage.

  • Use a sanitised fermentation vessel suitable for your brew size and type.

  • Maintain a consistent temperature in the fermentation chamber suitable for your yeast strain.

  • Aerate the wort before sealing the fermenter and attaching the airlock.

How to Pitch Yeast: Wrapped Up

Pitching yeast correctly is crucial for a successful fermentation and high-quality beer. It's essential to understand the different types of yeast, how much yeast to pitch, and the importance of pitching temperature and aeration.

By following the best practices outlined in this article, you can ensure a healthy fermentation and delicious beer.

  • Understand the different types of yeast.

  • Know how much yeast to pitch.

  • Recognise the importance of pitching temperature and aeration.

  • Follow the best practices outlined in this article.

Important Takeaways:

  • Understand the different types of yeast and choose the right one for your brew.

  • Rehydrate dry yeast in water before pitching into the wort.

  • Make a yeast starter for liquid yeast to ensure a healthy fermentation.

  • Pitch the yeast at the correct temperature and aerate the wort properly.

  • Monitor the fermentation for signs of healthy fermentation.

  • Avoid common mistakes by carefully reading and following the instructions that come with your yeast.

FAQ

Q: What is the proper way to pitch yeast for home brew beer?

A: The proper way to pitch yeast for home brew beer depends on the form of yeast you are using. Yeast comes in a dry form and a liquid form. If you are using dry yeast, you can simply add it directly to the wort without rehydration. However, if you are using liquid yeast, it is recommended to make a starter or rehydrate the yeast prior to pitching.

Q: Why is pitching yeast properly important for making the best mead possible?

A: Pitching yeast properly is important because it is the key to reducing the stress that yeast experience during fermentation. The yeast experience is key to making the best mead possible. By properly pitching yeast, you can ensure that the yeast is healthy and active, which will result in a successful fermentation and a flavorful mead.

Q: How do I pitch yeast in the dry form?

A: If you are using dry yeast, you can simply sprinkle the yeast directly on top of the wort. There is no need to rehydrate the yeast beforehand. However, it is important to make sure that the yeast is evenly distributed throughout the wort.

Q: How do I pitch yeast in the liquid form?

A: If you are using liquid yeast, there are a few different methods you can use to pitch the yeast. One method is to make a yeast starter. This involves making a small batch of wort and adding the liquid yeast to it. Allow the starter to ferment for a day or two, then add it to the main batch of wort. Another method is to rehydrate the yeast. To do this, follow the instructions provided by the yeast manufacturer. Generally, it involves adding the yeast to warm water and allowing it to sit for a specific amount of time before adding it to the wort.

Q: What is the recommended amount of yeast to pitch?

A: The recommended amount of yeast to pitch depends on the style of beer you are brewing and the gravity of the wort. As a general guideline, it is recommended to pitch 0.75-1 million cells per millilitre of wort per degree Plato. However, it is always best to consult a yeast calculator or a brewing reference guide to determine the precise amount of yeast needed for your specific batch of beer.

Q: Can I pitch too much yeast?

A: Pitching too much yeast can lead to a rapid and vigorous fermentation, which may result in off-flavours and other fermentation issues. It is generally recommended to pitch the appropriate amount of yeast for the style of beer you are brewing. However, it is always best to consult a yeast calculator or a brewing reference guide to determine the precise amount of yeast needed for your specific batch of beer.

Q: Can I reuse yeast from a previous batch?

A: Yes, you can reuse yeast from a previous batch of beer. This is known as repitching yeast. However, it is important to note that yeast can lose viability over time and may not ferment as vigorously as fresh yeast. It is recommended to use yeast within a few weeks of harvesting it from a previous batch of beer.

Q: What is yeast slurry?

A: Yeast slurry is a mixture of yeast and trub (sediment) that is collected at the bottom of the fermenter after fermentation is complete. It contains a high concentration of yeast cells and can be reused for future batches of beer. Before reusing yeast slurry, it is recommended to wash and store the yeast properly to ensure its viability.

Q: Can I pitch yeast directly into the mead must?

A: Yes, you can pitch yeast directly into the mead must. However, it is generally recommended to rehydrate dry yeast or make a yeast starter with liquid yeast prior to pitching. This helps to ensure that the yeast is healthy and active, which will result in a successful fermentation and a flavorful mead.

Q: Where can I learn more about pitching yeast and making mead?

A: If you are interested in learning more about pitching yeast and making mead, there are several resources available. Mead University is an online platform that offers courses and tutorials on mead making. You can also find information and tips on pitching yeast in brewing books and online forums dedicated to home brewing.