Coffee primarily ages by releasing gas, a process known as de-gassing. During this time, carbon dioxide trapped inside the beans escapes into the bag which sometimes causes it to puff up. This transformation affects how you should approach coffee extraction to achieve the best flavour. Some beans require a longer de-gassing time than others.
Very fresh coffee will have loads of CO2 , leading towards an under extraction which may lead to sour and weak flavours. This is referred to as ‘insoluble’ - meaning it’s hard for the water to dissolve the coffee. On the other hand, if you're using older coffee, there won't be much gas remaining, which allows the water to extract flavours more easily (more soluble). However, this may lead to over-extraction, resulting in a bitter and astringent taste.
The key to aging your coffee gracefully lies in pre-ordering. Ideally, you should allow your coffee to age (de-gas) for around 14 days post-roast.
You can discover your preferred flavour and aroma through experimentation and practice. If a coffee is very fresh and insoluble, you need to increase extraction to tease the flavour out. You can try dosing down by 0.5-1gm, using a finer grind or increasing your yield by 2-3gms.
If you’re working with coffee that’s a little older, dosing up by 0.5-1g, coarsening your grind, or dropping your yield by 2-3g will help.