What is Real Ale?

North_131116_RandyTapsAFirkin_fbReal ale is a top-fermented beer that completes its secondary fermentation in the container from which it is served. Cask-conditioned beers are real ales served from the brewer’s cask.

Flavor and texture is what real ale is all about. Lovers of cask-conditioned beers enjoy the broader range of flavors that result from the clear, naturally carbonated ale served at cellar temperatures. There is less gassiness, less head on the beer, more beer in a glass! Some devotees of the approach want to drink nothing else.


Like all ale, real ale results from the fermentation of malted barley by a top-fermenting yeast, distinguishing them from lagers. These yeasts provide some of the complex flavors observed in real ales. Hops are added at different stages of brewing to provide additional flavors. In real ales, dry-hopping is especially common.

Real ale is alive; it is not pasteurized or filtered. It is placed into its secondary container with priming sugar, which is rapidly consumed by the yeast to produce carbonation. The residual complex sugars provide complex tastes and continued fermentation. Once the secondary fermentation is complete, real ale is served from the same vessel. This might be the brewer’s cask (cask-conditioned), or the bottles used by a home brewer or specialty purveyors (bottle-conditioned).

nerax_20130320_servingapintThe cellarman’s job is as crucial as the brewer’s to the quality of the beer. Real ale should be clear, mildly carbonated, and served at cellar temperature. The lack of filtration means variable pressure and yeast remaining in the cask. The cask should not be moved once it is placed onto the stillage and chocked in place. These challenges are met by the cellarman with various techniques, such as careful tapping into the cask and adding finings (materials that clarify the beer by settling yeast and protein).

Real ale can be served by gravity from a tap, or drawn with a hand pump, electric air pump, or Scottish tall font. No pressurized or additional gas is added except atmospheric air as the cask is emptied. The ideal serving temperature is cellar temperature, about 55° F. The warmer temperature and infusion of oxygen from replacement air affects the ale. Some of the initial changes can be pleasant-tasting, but over-oxidation spoils the beer. Once opened, cask-conditioned beer should be consumed quickly: 48 hours in summer, 72 hours in winter. It is particularly interesting to note the changing flavors from a cask over the days from tapping until it is finished.

Most importantly, Real Ale is best consumed in the company of your friends and other enthusiasts. We hope you enjoy NERAX, NERAX North and our other events. Please also support your local brewpubs and bars who present Real Ale year round.


Find Cask Ale in New England

While we do our best to ensure these listings are accurate, just as at NERAX, nothing is guaranteed with cask. Beers may kick, or not drop bright on time. If you find an error or out-of-date information, please send a note to .
For cask beyond New England, please see Alex Hall’s Cask Beer Finder.

  • Serves cask every day
  • Usually has cask
  • Serves cask on a regular basis
  • Serves cask – Contact to confirm

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Cask Resources

Real Ale News and discussion

Real Ale Resources

  •  Alex Hall’s Cask Beer Finder – Lists over 600 locations in North America serving cask-conditioned beer
  •  CAMRA – CAMpaign for Real Ale
  •  Softspile – Sending American cask-conditioned beer to the Great British Beer Festival

Real Ale Equipment and Suppliers

Is Real Ale Vegan?

A discussion of beer clarification additions in cask beer

Michael Labbe

Brewery Engineer, Lord Hobo Brewing Company, Woburn MA

As the former Head Cellarman for many years at NERAX festivals, one of the questions I have heard most often is, “Is Real Ale vegan?” The answer is not necessarily cut and dried. Ingredient choices and personal interpretation are both factors. The discussion begins and ends with what are called finings.


These are “process aids” that are added to a cask to accelerate clarification of the beer. Traditional finings are positively charged particles which, when added to beer, bind with yeast in suspension, which is negatively charged. As the finings and yeast bind together, they get heavier and precipitate out of the beer, clarifying it much more quickly than waiting for the yeast to settle on its own.

Isinglass finings are a traditional choice, and are still in common use today. Isinglass is a collagen derived from the dried swim bladders of certain fish. In practice, Isinglass added to a cask sediments out quickly, so never makes its way out of the cask. For this reason, many argue that it is not actually an ingredient, but merely a process aid in short term contact with the beer, that is not present in the glass. Others disagree, arguing that from the moment Isinglass is added, a cask is no longer vegan, regardless of whether the Isinglass is consumed or not. In this case, it’s a very personal choice with no right or wrong answer.

The discussion is made much clearer (pun intended) with the advent of Isinglass alternatives that are vegan-friendly. One example is Biofine® Clear by Kerry Ingredients and Flavors. Biofine® Clear is a colloidal solution of silicon dioxide (Silica), the most abundant mineral in the earth’s crust. According to Rubens Mattos, D.Sc., of Kerry, “Biofine Clear is a colloidal silica which is positively charged at the pH of beer. Thus it combines with the negatively charged yeast cells and increases settling velocity by increasing the size of the suspended particles.” Biofine® Clear works in exactly the same manner as Isinglass!

The NERAX stillage is stocked with casks that may come to us from the brewery fined with Isinglass, fined with Isinglass alternatives, fined by us at the festival, or not fined at all. CASC has standardized on the use of Biofine® Clear for all on-site fining at NERAX festivals. This means that any cask that is fined at NERAX is vegan-friendly in the strictest possible sense. This year our program includes fining information for the US beers on the stillage, so that you can make an educated decision based on your own determination. For those beers that are not specified (such as the UK beers), a safe assumption is that the cask was fined at the brewery using Isinglass.

*Biofine® is Kerry’s trade name for finings, and includes both Biofine® and Biofine® Clear. While Biofine® Clear is vegan-friendly, Biofine® is Isinglass.