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WHY Coffee tastes bad after 20 Minutes

You've brewed your coffee for the thousandth time and you've always boggled your mind over to why your cup of joe tasted bitter and rancid after cooling for the past 20 minutes. Simply put, the villain that's causing this.. is called Oxidation, also known as, Staling.

What is Oxidation/Staling?

In Geek terms: Oxidation occurs when one or more electrons move from one chemical to another, producing two different compounds. In Coffee oxidation, there are 2 sources of oxygen, 1) Dissolved oxygen in your brewing water & 2) The air. This oxygen then reacts with free hydrogen atoms and flavorful compounds found in your cuppa. The pH of your coffee increases as less hydrogen ions are present (Hydrogen ions are acidic). Henceforth, more bitter & stale tasting coffee.

In Layman terms: Your tastebuds taste more bitter and stale flavours as delicious aromats, acids and oils compounds are oxidised away.

Can I prevent Staling?

Lower temperatures means slower rates of oxidation. This means flash brews and cold brews stay fresh longer than hot brewed coffee. Staling is ultimately unrestrained unless your coffee is kept in an atmosphere of 0% oxygen and has no dissolved oxygen! Do let us know if you have found a secret of such! 

Practical measure wise? Brew your coffee through a cold brewing method like cold brew or flash brew and ensure that your coffee is exposed to as little air in your favourite tumbler if you wish for coffee that tastes fresh longer! Otherwise, why bother keeping your coffee for durations of time? Just brew fresh with our Instant Drip bags and slurp delicious freshly brewed coffee anytime, anywhere.

To Conclude

The reason why your coffee tastes bitter, rancid, sour & "you name it!" after 20 minutes is because of Oxidation. Just imagine all your delightful and delicious acids, aromats and oils flavour compounds rotting away to horrible stale tasting compounds. And for the geeks, the increased pH of coffee, hence the perceived flavour for bitterness and loss of acidity.

A good taste test? Taste the drastic change in flavour profile of that pot of brewed coffee in your favourite diner or office once at 9am in the morning and another 6pm in the evening or just brew a fresh cuppa and let it sit for 20 minutes! 

Some recommend 20 minutes is all you've got before your coffee is Al Dente Stale while others recommend an hour. On our side? We don't like to condemn any timings but we like to recommend always brewing freshly roasted coffee and enjoying your cuppa! After all, people have different standards of bitterness & we just want you to find your favourite coffee and most importantly, Enjoy coffee and Stay Mootivated with your hustle!


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