India pale ale (thing)

Friday night, 6:32 PM. Another demanding week fades behind your heels, and if you are at all like me, a cool one in the form of a beer will be your relaxation tipple of choice. As your wearied mind begins to loosen and give way from work pressures to the slowly softening lull of alcohol, the last thing on your mind will be the whys and wherefores regarding the origins of your beer.

It is an interesting thought however, why does the beer you are drinking taste as it does? There is a fair chance that you don't really care; as long as it is cold, and gets you nicely buzzed after a few glasses, then maybe not a lot else matters to you. In that case you are the dream consumer of mass produced beer companies. However, all beer has a distinct taste, and that taste is governed by a few concrete factors - factors not always decided by the brewer before they brew the beer. Take for instance a pan-global beer such as Foster's. This was once a noble lager brewed exclusively in Victoria, Australia. It had a distinctive taste that ensured a devoted local following. Once it became a global brand many factors came into play that varied and shaped the flavour of the beer - none of them to do with scintillating ideas from the brewer. In Australia, the main influence was government alcohol excises. Sometime during the 1990's, the Australian government changed the tax levied on alcohol from one based on wholesale price to one based on alcohol by volume. A beer fully fermented and sold at 4.9% alcohol suddenly became a whole lot less attractive from a sales manager's point of view. Brewers were instructed to drop the alcohol content for a range of beers to ensure they remained at a competitive price point in the market. A drop of 0.7% alcohol per volume results in roughly 15% less alcohol for a 4.9% beer, and has a marked effect on the final flavour of the beer. In other words, government policy has changed the flavour of what you drink on a Friday night.

What has all this got to do with India pale ale? More than you may think. This mid-to high alcohol ale is a classic beer style that originated when British brewers were required to brew beer for export to the thriving and far-flung, yet thirsty Raj colonists. It really should have died out with British colonization of India, but it didn't - it is a style still brewed by beer makers around the world for it's distinctively bitter and dry flavour, strong carbonation and hoppy aroma.

India pale ale is another case of a beer style being dictated by other factors than the brewer - and this time geography was the influence. An Eighteenth Century boat journey from Britain to India was no brief affair. Early attempts to transport British ales resulted in sour and unpleasant refreshers for the thirsty ex-pats. The long journey and exposure to equatorial temperature extremes promoted rampant bacteria growth in standard ales, and the thirsty hoards rapidly became unsettled. A beer was needed that would survive the journey intact, and that meant a beer with mighty bacteria resistant characteristics. The man that fulfilled this brief was George Hodgson.

Hodgson was the brewer at the Bow Brewery in East London towards the end of the Eighteenth Century. He took the long held knowledge that alcohol created a less than perfect medium for microbial growth, and that hops had an unexplainable, yet definite ability to inhibit bacteria, then he amplified these facets of the beer. India pale ale was brewed firstly with a higher alcohol content. Add to this a high level of hops (in this case, primary hopping, added to the wort before fermentation.), then a good dash of secondary hopping (adding hops to the fermented beer, which increases the bitter hops aroma), and finally a over-generous prime (priming is adding some form of sugar to the fermented beer, and provides the drink with it's characteristic carbonation). This resulted in a reasonably strong beer, with a highly bitter palate, strong carbonation and a thin and fruity, bitter aroma. Hallmarks of a good India pale ale.

What Hodgson and his grateful drinkers could not have known was just exactly why the hops were so efficient at keeping the beer fresh after its long journey. It is now apparent that the preservative secret lies with a nifty little group called humulones. Otherwise known as α-acids, these compounds are found in abundance in hops, but they are insoluble in water - which makes their preservative abilities null. When the primary ingredients of beer, malted barley and hops, are first cooked together in an aromatic slop called the wort, the humolones undergo a significant transformation. The heat is a precursor to a new group of isomeric chemicals called isohumolones, and these are soluble in water. These compounds have several analogues in the hops; cohumulone, adhumulone and prehumulone, which differ only in the number of carbon atoms in the side chains. For the average drinker, this bunch of big names will be only of interest for the bitter flavour characteristics (and sometimes floral aroma) they provide to a beer. To the original brewers of India pale ale however, they represented much more. These α-acids have strong bacteriostatic properties, meaning they won't kill bacteria outright, but they will definitely inhibit their growth.

India pale ale will not be an easy beer style to find, as only a handful of brewers around the world continue to carry the flame. There is no practical reason for them to make the beer; they do so only for the distinctive flavour that results from such a complex history and unique method of production. Long may it be so. I can only give you a tip for an Australian IPA; the Malt Shovel Brewery's James Squire India Pale Ale, which is a relatively new beer that exhibits all the desired characteristic of alcohol, aroma, bitterness and carbonation. Thank God for Friday nights.