International beer day: chemistry and beer flavors

Acids – bitterness
Acids don’t only play a big role in many of our industries and segments, they also play a huge role in the taste of beers. When you think acids, you think sour. That is not always the case (though sometimes it is as you will read about later). Hop supplies so-called alpha-acids to the beer, which are responsible for the bitter taste in beers and have long been used for their preserving properties. Sound familiar? Many of the organic acids used in animal nutrition are used for the same reason. 
A beer style known for its exceptional bitterness and expressive hop flavors is the IPA (India Pale Ale). That beer type is said to have originally been made more bitter than usual to increase the preservative functions of the alpha acids so that the beers could survive the long trip from Britain to India and provide refreshments to the Brits there. After a while the taste simply became very popular and that popularity continues globally today. 

Acids – acidity
As mentioned some acids that can play a role to make beers taste more sour. Well established beer styles that are notably sour include Belgian Geuze and Lambic and German Berliner Weisse and Gose. Though all distinct beer styles each of them is noticeably more acidic than most other beers on the shelve today. Many acids are responsible for this pH reduction but the main responsible is usually acetic acid followed by formic acid. Both acids that Perstorp has a long history with. Acetic acid was one of the first products produced by Perstorp 140 years ago and formic acid is produced by Perstorp today with applications in animal nutrition and leather tanning.
The acids that make these beer styles more acidic are produced by natural strains of bacteria that convert the wort alongside or even before the yeast does. Acid producing bacteria occur naturally so the beers that were drunk in more primitive cultures where most likely all more acidic then we are used to today. 

Esters – subtle and not-so-subtle flavors added by yeast
Once you start to hear about esters, there is no turning back. Esters can form when acids and alcohols react. Some beer styles are known for their high amount of esters that can be interpreted to tase like banana, anise, apples and much more. These are more subtle flavors created by the yeast. Rule of thumb is that the more you push the upper limit of the preferred fermentation temperature of the yeast, the more esters it will produce. Some yeast strains also just produce infamously large amounts of specific esters. Styles known for high ester impact on the flavor are German Weizen/Weissbier (banana and clove) and Belgian Saison (floral, citrus). 
‘Famous’ Perstorp ester based products include ProPhorce™ SR, ProSid™ MI 700 and Pevalen™. We also supply both acids and alcohols that are esterified to be used in the synthetic lubricants segment. 

Alcohol – not all alcohols are equal
Everybody knows that beer contains alcohol. But not all alcohols are equal. Generally speaking alcohol can be broken down into Ethanol and Methanol. Ethanol is the one you want in beer but harmless amounts of methanol may also be found. Especially heavier beers may also contain some so called Fusel alcohols. They can give the beer a more alcoholic taste and scent that gives some strong beers this warming sensation. As with all things balance is key. Too much fusel alcohols can ruin a beer, for example making it smell of kerosine. 

Methanol alcohol is an important starting point for many of Perstorp’s processes to create our products. That is why being able to produce it in a low-carbon, renewable and circular thanks to Project Air means so much to us. 

Essential oils – hop aroma
Besides bitterness, hop also attributes more subtle hop flavors that can range from earthy and complex to downright citrussy and juicy. Those flavors are created by the essential oils that are also found in hops. A newer beer style known to focus on extracting these wonderful hop flavors without a corresponding bitterness is the New England IPA style. If you get these fresh you could mistake them for a fruit juice. 
Many positive benefits are attributed to essential oils. The essential oils that are used in ProPhorce™ PH have been added due to their synergistic effect on the effects of organic acids in animal nutrition. 

Salts: the secret to flavor expression
Some beers historically proved notoriously hard to copy. Usually that had something to do with the water profile in the city where they originated. This holds true for IPA’s from Burton-on-Trent (UK), world renowned Pilseners from Plzen in the Czech republic and the aforementioned Gose from Leipzig. Though these water profiles are all very distinct, salts are generally used to mimic the effect that these local water profiles would have on taste. Calcium sulfate, calcium chloride, Epsom salt, sodium chloride and many more are used by brewers to e.g. emphasize the expression of bitterness (Burton-on-Trent), subtle balance (Plzen) or add a slight salty flavor (Gose beers).

You can find several salts in Perstorp’s portfolio too. A particularly product worth mentioning is ProPhorce™ AC 299 that is a sodium formate based dry solution to help manage the dietary electrolyte balance of animals.

Chemistry is everywhere
This is yet another example that chemistry is everywhere. We’d love to hear from you if there are notable molecules that we missed in this article. 
Interested in reading our previous publications to celebrate international beer day?

Similarities between working for Perstorp Animal Nutrition and brewing beer >>

What beer and silage have in common >>