British Brewer

Recreating the perfect British Pint

20 January
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Brewing on a budget – Borrowing Yeast

Yeast StarterAs part of the continued deep dive into specific ingredients and techniques (so far we have dug deeper into yeast and reviewed water treatment) I thought a further post on yeast was in order especially given the cost of quality yeast. Its expensive.

As I mentioned in an earlier post on why I brew, its not just the pleasure of drinking high quality fresh ale, or the enjoyment of simply brewing, but also the lower cost of home made ale that stokes my passion for homebrew.  Brewing your own real ale is very economical. I was reminded as I toured the liquor store today and noticed a 6 pack of Fullers ESB on the shelf for $12 (or $2 a bottle), and remembered I have 2 cases (48 bottles) of my own version (though still not up to Fullers quality) in my cellar that cost me approx $4.75 per 6 pack ($0.79 per bottle).  Given I like to use the more expensive liquid yeast from Wyeast or White Labs I find yeast is the most expensive ingredient in my brews. These yeasts have reliable attenuation percentages and produce very consistent results every brew. I have never had a bad batch.  But they are expensive, most being over $6 a packet.  What also doesn’t help is I am often left guessing what type of yeast to purchase for a recipe, e.g. is it a London Ale, London Ale III, or a Thames Valley strain?

But what if I could get the right yeast and pay nothing (except for the one time cost of a single bottle of beer). I could bring the price of a 6 pack of Fullers ESB down to $4 (or $0.66 per bottle) helping my budget somewhat and deliver an even closer match to the original I am trying to clone.

This brings me to the main reason for the visit to my local quality liquor store (as I rarely buy beer except for research purposes), to acquire a sample of 2007 bottle conditioned Fullers Vintage Ale.  As noted in my prior post, I am unhappy with the results of version 1.0 of my Fullers ESB clone.  As part of my research into figuring out how to improve the recipe I have been investigating how to improve the malt, hops and yeast mix.  I have managed to finally find a reliable source for the appropriate hops but got stuck on the yeast. Fullers, like most breweries, is very secretive around its yeast as so much of the flavour and character of the finished ale comes from it.  During my research I was browsing some recipe web sites and found a post on a bulletin board where a homebrewer from England was trying to replicate Fullers London Pride using some yeast grown from a yeast sample he had lifted from some bottle conditioned Fuller 1845 Ale.  Much like homebrew, bottle conditioned commercial beers are naturally carbonated in the bottle using residual yeast and priming sugar leaving a sediment on the bottom of the bottle. The sediment is rich with yeast cells and, with a little care and attention, these cells can be reactivated and grown to be used again in whatever beer you choose. In my case any Fullers clone I might make in the future.

But isn’t all beer sold in the USA pasteurized? I always thought so. So what commercial beers are out there that we could use to create our own free supply of yeast?  The answer appears to be not many.  As a rule almost all imported bottled and keg beers are pasteurized, the reason given to preserve freshness and enhance shelf life (though this point in hotly debated, I can attest to having regular gravity beers in my cellar for months and they continue to improve with age).  Furthermore almost all domestic US bottled beer is also pasteurized though domestic US keg beer is typically unpasteurized and “fresh” (with the exception of the mega-breweries such as Bud who pasteurize everything).  But recently the rules appear to be slowly changing. It is now possible to get imported and domestic bottled conditioned ales for higher gravity brews. I have noted Ringwood, Fullers 1845, Fullers Vintage Ale, and Sam Smiths Organic Ale from the UK and Shipyard Barleywine and Sierra Nevada from the US all available unpasteurized and bottled conditioned in the US market.

So how do we take a sample of bottled conditioned ale and re-culture it for use in your typical 5 gallon batch of homebrew?

  1. First acquire some bottled conditioned ale that matches either the style you are shooting for or from the same brewery that brews the ale you are attempting to clone (chances are its the same strain)
  2. Pour yourself a drink, make sure to save ~20% of the ale bottle, including all the sediment from the bottom
  3. Assemble the following to make a “yeast starter” :
  4. In a saucepan bring to a boil 8 oz of water, add Wheat DME and the hop pellets and boil for a total of 10mins
  5. After 8 mins add yeast nutrient (optional)
  6. Cool rapidly, I partially submerge the saucepan in a sink full of ice cold water and stir vigorously, this also aerates the liquid
  7. Once the liquid is cooled to 80ºF pour into a clean, sanitized flask or carboy
  8. Add the remaining 20% of the bottle conditioned ale, including sediment, from the bottle you purchased
  9. Insert stopper and airlock and keep at a constant 68-75ºF. The yeast should come back to life within 3-4 days.
Yeast Harvesting Materials

The Equipment

Mixing in the Wheat DME

Mixing in the Wheat DME

Source Ale

Pour drink, saving 20%

Yeast Nutrient

Add yeast nutrient after 8mins

Cooling starter to 80%

Cooling rapidly in cold water

Final product

Transfer to flask, add ale with sediment

Once the yeast is active you can either use it or place in the refrigerator to sleep.  Make sure to keep some back to re-culture again for another brew.  Yeast can stay healthy for up to 3 months in the fridge, so make sure to re-culture a batch before 3 months to keep the strain alive or you will just have to go out and actually BUY beer, how does that work with the budget!

Other resources:

  • For a complete list of breweries where White Labs and Wyeast strains originate you can look here.
  • For a list of bottled conditioned ales capable of harvesting yeast go here.
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20 December
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What the “flocculation” are you talking about?

Hopefully the title of this blog post grabbed your “attenuation”.  For those who don’t get the joke, this is a post about yeast.  We provided a 101 background in the “Getting Started Series” post but now its time to dig in a little deeper into this magical little fungus.

Top fermenting yeast in an open fermenter, smells yummy

Top fermenting yeast in an open fermenter, smells yummy

Yeast is truly a magical mould, there were times in our past, before purification systems, when water was unsafe to drink. Ale and wine were seen as staples and a safe form of nutrition (I would argue that with the quality of our food today homebrewed ale remains a safe form of nutrition). Yeast is still considered a powerful nutrient, rich in both B-complex vitamins and an anti-bacterial being the basis of penicillium notatum, the foundation of modern antibiotics. But to beer drinkers around the world yeast is know as the magical fungus responsible for converting sugar into alcohol and putting bubbles in our beer.

God made yeast, as well as dough, and loves fermentation just as dearly as he loves vegetation. – Ralph Waldo Emerson

Types of Yeast

First it is important to differentiate between the two styles of yeast used to brew.  The first is saccharomyces uvarum, often called lager yeast, in which the yeast settles and ferments on the bottom of fermenter.  This type of yeast works at much lower temperatures and ferments more of the sugar leaving a drier, crisper beer.  This yeast is typically used to brew Pilsners and Lagers. It is believed there are very few strains of lager yeast with all lager yeast descending from only 2 primary strains.

The second type of yeast is saccharomyces cerevisiae, often called ale yeast, in which the yeast rises to the surface of the fermenter causing a thick layer of foam called krausen.  This is the type of yeast used to brew all British and most European beers.  There are numerous strains of this type of yeast, each providing very distinctive characteristics you should consider when planning a recipe of which I have highlighted 5 important ones below:

1) Flavour – Ale yeast strains work by synthesizing the sugars and other enzymes derived from the malt. The flavours most commonly associated with ale are esters, resulting in an “ale taste,” as well as more-easily-described flavours such as apple, banana, and pineapple. Combinations of yeast strain, malt, and temperature can be responsible for chemicals causing other flavours, such as a cidery taste or butterscotch.

2) Attenuation – Is a percentage that measures the amount of sugar converted into alcohol during the fermentation process. Lower attenuating yeasts will leave more sugars behind leading to a sweeter taste.  Higher levels lead to a drier taste with alcohol notes.  Most yeast manufactures provide an observed attenuation level for each yeast strain which a brewer can then use when considering the target ABV and taste of a recipe.  I find it helpful to keep your own chart of observed attenuation for the yeast strains you use.  The ranges provided by the suppliers are fairly accurate but will vary depending on your own brewing conditions.  No one wants a yeast to under-perform.

3) Flocculation – Refers to the clumping together of yeast cells once the sugar has been fermented into alcohol.  As the yeast cells clump they begin to fall pulling down other matter suspended in the beer. Larger clumps tend to pull down other particulates suspended in the beer and lead to brighter, clear ales without the need for filtration or additives, know as “high” flocculation. Lower levels or “low” flocculation yeast might need additions such as Isinglass during the secondary fermentation phase to help pull down some of the suspended yeast or proteins left behind.

4) Alcohol Tolerance – Most yeast suppliers supply an ABV tolerance level yeast can reproduce under.  Ales with a high ABV such as Imperial, Barleywine or Old Ales need to be fermented with yeast strains with a high ABV tolerance say 10%. Some varieties of Barleywine that are bottle conditioned will require the use of Champagne yeast to ensure carbonation is successful in the bottle.  Remember to check the tolerance of your chosen yeast is higher than the target ABV.

5) Fermentation Temperature – Refers to the recommended temperature the yeast will perform optimally.  Too warm can lead to off flavours in the ale, too cold and the yeast head on top of the fermenter can fall prematurely and cause a stalled fermentation.

The most important stage for yeast in the brewing process is being pitched into the primary fermenter to begin its work.  Make sure the temperature of the wort is optimal at around 75-80°F, the wort is well aerated to provide the yeast cells the oxygen they need.  Most important make sure the yeast is working.  This can be done by creating a yeast starter.  Bring a pint of water to boil, add some DME, and boil for 15 mins.  Place in a jug, cool, and pitch the yeast. Insert and airlock and watch the yeast go to work.  A healthy yeast will be fully active within 24 hours.

Remember you can replace a yeast but you cannot replace a brew gone bad.  Hope this information helps, I find it most useful when selecting the right yeast to use for a specific recipe. Next up in our deeper dive into ingredients will be the water.

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01 December
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