Brewing Beyond Beer: Creative Ways To Reuse Yeast

Reusing yeast is a cost-effective way to brew beer and can be done in a few different ways. Commercial breweries will crop the yeast from the top or bottom of a fermenter just after the primary fermentation has finished. Home brewers can reuse yeast by brewing beers consecutively, sipping out as usual and leaving half an inch of beer in the bottom. Over a period of several weeks, the yeast will settle to the bottom and can be used to create a starter for the next batch of beer.

Consecutive brewing

There are a few things to keep in mind when reusing your yeast. The most important to consider is carryover between batches. It’s generally better to reuse yeast beginning with lighter-colored, lower alcohol, less hoppy beers, to darker, heavier ones. If you start with darker beer, you risk introducing some residual character to the second beer. Similarly, you wouldn’t try to reuse Rauchbier yeast for a Helles. Also, higher alcohol and hopping rates can stress the yeast cells more, shortening their useful lifetimes. In addition, keep in mind that very high pitching rates will give you less fermentation character, such as esters and (positive) phenols.

A commercial brewery will reuse yeast by cropping the yeast from the top or bottom of a fermenter just after the primary fermentation has finished. The yeast can then be used in the next batch which benefits from large amounts of really viable yeast and a very short lag time before fermentation. In fact, there are some breweries that take the concept to the extreme. A brewery in the US cultured yeast from a bug encased in amber and made a beer with it. It’s good to know that yeast is hardy enough to survive 45 million years encased in amber, but what are the practicalities of the home brew reusing yeast?

Over a period of several weeks, the yeast itself will settle to the bottom and this yeast is the portion you need to create a starter for your next batch of beer. On the day before you brew, add some wort to your yeast to create an appropriately sized yeast starter for your next batch. If you want to use your yeast across several batches, you can either split your starter and store part of it for later use or repeat the entire process to collect yeast from the primary again. If you do collect yeast across several generations, I recommend not exceeding 4-6 generations of reuse as eventually some wild yeasts or bacteria will make their way into your yeast.

Yeast slurry

To create yeast slurry, you can sift out the yeast from the bottom of the fermenter after the primary fermentation of your starting beer. Leave half an inch of beer in the bottom of the fermenter and give it a swirl to get some of the yeast slurry into suspension. You can then pour the yeast slurry into a sanitized jar or container and place a cover on it for the first few days. A piece of sanitized foil secured with a rubber band will allow CO2 generated by the yeast to escape. After a few days, you can put a lid on the container but keep an eye on it and vent any carbon dioxide that may build up.

You can then use the yeast slurry to brew another batch of beer. Brewing beers consecutively, one after the other, is the easiest way to reuse yeast. When you move the beer from a primary to secondary fermenter or to bottles, you can see a whole lot of yeast that is still viable to brew with. An easy way of reusing it is to put another batch of beer on the used yeast slurry, so you need to brew a beer the same day you rack your original to secondary and sift the new beer directly onto the yeast cake.

There are a few things to keep in mind when reusing your yeast. The most important to consider is carryover between batches. It’s generally better to reuse yeast beginning with lighter colored, lower alcohol, less hoppy beers, to darker, heavier ones. If you start with darker beer, you risk introducing some residual character to the second beer. Similarly, I wouldn’t try to reuse Rauchbier yeast for a Helles. Also, higher alcohol and hopping rates can stress the yeast cells more, shortening their useful lifetimes. In addition, keep in mind that very high pitching rates will give you less fermentation character, such as esters and (positive) phenols.

Carryover between batches

When reusing beer yeast, it's important to consider carryover between batches. Start with lighter-colored, lower alcohol, less hoppy beers, to darker, heavier ones. If you start with darker beer, you risk introducing some residual character to the second beer. Higher alcohol and hopping rates can stress the yeast cells more, shortening their useful lifetimes.

A commercial brewery will reuse yeast by cropping the yeast from the top or bottom of a fermenter just after the primary fermentation has finished. The yeast can then be used in the next batch which benefits from large amounts of really viable yeast and a very short lag time before fermentation.

Over a period of several weeks, the yeast itself will settle to the bottom. This yeast is the portion you need to create a starter for your next batch of beer. On the day before you brew, add some wort to your yeast to create an appropriately sized yeast starter for your next batch.

You can reuse the same yeast for around 4 – 5 generations of beer before having to purchase any new yeast. The easiest way to reuse yeast is to brew beers consecutively, one after the other. When you move the beer from a primary to secondary fermenter or to bottles, you can see a whole lot of yeast that is still viable to brew with.

Starter for next batch

The easiest way to reuse yeast is to brew beers consecutively, one after the other. When you move the beer from a primary to secondary fermenter or to bottles, you can see a lot of yeast that is still viable to brew with. An easy way of reusing it is to put another batch of beer on the used yeast slurry. You can also sift the new beer directly onto the yeast cake.

There are a few things to keep in mind when reusing your yeast. The most important to consider is carryover between batches. It’s generally better to reuse yeast beginning with lighter-colored, lower alcohol, less hoppy beers, to darker, heavier ones. If you start with a darker beer, you risk introducing some residual character to the second beer. Similarly, I wouldn’t try to reuse Rauchbier yeast for a Helles. Also, higher alcohol and hopping rates can stress the yeast cells more, shortening their useful lifetimes. In addition, keep in mind that very high pitching rates will give you less fermentation character, such as esters and (positive) phenols.

Over a period of several weeks, the yeast itself will settle to the bottom and this yeast is the portion you need to create a starter for your next batch of beer. On the day before you brew, add some wort to your yeast to create an appropriately sized yeast starter for your next batch. If you want to use your yeast across several batches, you can either split your starter and store part of it for later use or repeat the entire process to collect yeast from the primary again. If you do collect yeast across several generations, I recommend not exceeding 4-6 generations of reuse as eventually some wild yeasts or bacteria will make their way into your yeast.

A commercial brewery will reuse yeast by cropping the yeast from the top or bottom of a fermenter just after the primary fermentation has finished. The yeast can then be used in the next batch which benefits from large amounts of really viable yeast and a very short lag time before fermentation. In fact, there are some breweries that take the concept to the extreme. A brewery in the US cultured yeast from a bug encased in amber and made a beer with it. It’s good to know yeast is hardy enough to survive 45 million years encased in amber, but, what are the practicalities of the home brew reusing yeast.

Wild yeasts or bacteria

When reusing yeast, it's important to consider carryover between batches. It’s generally better to reuse yeast beginning with lighter colored, lower alcohol, less hoppy beers, to darker, heavier ones. If you start with darker beer, you risk introducing some residual character to the second beer. Similarly, I wouldn’t try to reuse Rauchbier yeast for a Helles. Higher alcohol and hopping rates can stress the yeast cells more, shortening their useful lifetimes. In addition, keep in mind that very high pitching rates will give you less fermentation character, such as esters and (positive) phenols.

Over a period of several weeks the yeast itself will settle to the bottom and this yeast is the portion you need to create a starter for your next batch of beer. On the day before you brew, add some wort to your yeast create an appropriately sized yeast starter for your next batch. If you want to use your yeast across several batches you can either split your starter and store part of it for later use or repeat the entire process to collect yeast from the primary again. If you do collect yeast across several generations, I recommend not exceeding 4-6 generations of reuse as eventually some wild yeasts or bacteria will make there way into your yeast.

A commercial brewery will reuse yeast by cropping the yeast from the top or bottom of a fermenter just after the primary fermentation has finished. The yeast can then be used in the next batch which benefits from large amounts of really viable yeast and a very short lag time before fermentation. In fact there are some breweries that take the concept to the extreme. A brewery in the US cultured yeast from a bug encased in amber and made a beer with it. It’s good to know yeast is hardy enough to survive 45 million years encased in amber, but, what are the practicalities of the home brew reusing yeast.

The easiest way to reuse yeast is to brew beers consecutively, one after the other. When you move the beer from a primary to secondary fermenter or to bottles you can see a whole lot of yeast that is still viable to brew with. An easy way of reusing it is to ahead and put another batch of beer on the used yeast slurry, so really you need to brew a beer the same day you rack your original to secondary and siphon the new beer directly onto the yeast cake.

Alternatively, this is my preferred method of reusing yeast. After primary fermentation of you starting beer siphon out as usual and leave half an inch of beer in the bottom. Give the fermenter a swirl to get some of the yeast slurry into suspension. You will then be able to pour these into a sanitized jar or container and place a cover on for the first few days, a piece of sanitised foil secured with a rubber band will allow CO2 generated by the yeast to escape. After a few days you can put a lid on but do keep an eye and vent any carbon dioxide that may build up.

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