Oxidation - Why Coffee Gets Stale?

More likely than not, the coffee you drank this morning is some of the most flavourful and delicious coffee ever consumed. But on that rare occasion we stumble across a cup of coffee that just tastes stale. 

The reason behind stale coffee is a process called oxidation. Once a coffee is roasted, it is immediately under attack by its environment. Heat, moisture, and other aromas ( i.e. keeping coffee in your spice cupboard ) can change the flavour of the coffee, but one of the greatest factors in coffee staling is oxygen. Coffee grounds are full of various oils, chemical compounds, and acids. These compounds, referred to collectively as "solubles," give coffee its flavour. They're extracted from the grounds in the brewing process and give coffee its quintessential "coffee" taste and smell. Once coffee beans touch air, coffee flavour and smell starts to degrade as solubles start to oxidise — similar to iron becoming rusty when it’s exposed to oxygen for too long. This is why roasters package their beans in vacuum-sealed containers, so the beans are no longer in contact with oxygen from the air. You can even notice the change in taste just minutes after grinding your coffee. This is why specialty coffee houses grind and brew coffee in small batches.

Pre-Ground Coffee Beans Vs Whole Beans?

The main difference between pre-ground and whole-bean coffee is freshness, flavour and scent. When using pre-ground coffee there is the convenience of not having to grind your own coffee and doing it improperly. Although, you are taking away from the freshness of your home brew and the length of time it has until it goes stale. The benefit of whole bean coffee is having the freshest cup possible every time if properly stored. It is hard to compare the freshness of pre-ground coffee and whole-bean coffee if you have never experienced a fresh cup of whole-bean coffee when ground just minutes before being brewed. The aroma and flavor of the fresh brew is highly noticeable.

When opening a packet of pre-ground coffee it should be brewed immediately. Even vacuum sealed jars won't stop it from going stale, once oxygen hits the pre-ground coffee it's a race against time. Leaving your pre-ground coffee over night in your Barisieur or in a vacuum sealed cup will make almost no difference in taste.

The choice is entirely up to you. You can play it safe and take advantage of the convenience of pre-ground coffee or enjoy the freshness of a cup of whole-bean coffee.

How to avoid brewing stale coffee with the Barisieur? 

When using your Barisieur, to get maximum flavour we suggest using fresh roasted coffee beans and grinding them before starting your brew on demand. On the other hand when preparing the Barisieur for your morning wake up, the best way to get a tasty cup is by using fresh roasted beans and grinding them coarsely before going to bed. But as we all know, we can't stop the damaging effects of time.

Let us know how you get on. 

All the best,

Josh Renouf

Founder | Barisieur & Joyresolve

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