The age old question of 'is fresh coffee best?' is a good one, but there needs to be some clarity on what 'fresh' means in regards to roasted coffee.
Too much pointless arguing and misunderstanding is the result of the murky nature of 'fresh coffee'.
To start with, let's talk about what the ideal cup of coffee tastes like. Most of us can agree that the ideal coffee is a well-brewed (properly extracted) cup of coffee that has used roasted coffee at its peak intensity of pleasurable flavours. Sounds about right? A coffee that is at its peak of positive flavours.
A byproduct of roasting coffee is CO2 gas that is released after the coffee comes out of the roasting machine and can take up to 3 weeks to full be released from each coffee bean depending on how light the coffee has been roasted.
The effect that CO2 has on you while you drink a coffee with it is a kind of muted flavour that feels a little 'sparkly' or gassy. The coffee does not taste open, as sweet as it will be, and there is not much clarity of flavour. Essentially, it's not at its peak of intensity of pleasurable flavours.
After roughly 48 hours, a roasted coffee begins to 'open up' and show you what it really tastes like. This 'open and honest' flavour can last up to 1-2 months in the best case! This usually is not the case though and the window of 'intense and open' usually peaks around the 1-2 weeks after roasting date.
What is 'FRESH' coffee?
It's a vague question that can have a range of answers. Generally, we'd say any coffee that is less than one month from roast date. A lot of people tend to think the fresher the better though, which is incorrect in almost all cases. Obviously there is the matter of preference, however it's not better than slightly aged coffee (and most coffee professionals would agree).
What is the optimal period to rest coffee before you start brewing it?
It really depends on how it was roasted, and which processing method was used to create the coffee in the first place. If it's a light roast it needs more time to degas, as a lightly roasted coffee has harder beans meaning the gas has a harder time getting out. On the other hand, a medium or a darker roasted coffee is more brittle from the roasting and therefore the gas has a much easier time being released.
So a general rule of thumb would be that lightly roasted coffees like ours should be rested for around 5 days before you start with them and a dark roasted coffee you could start with maybe on day 2 or 3 after roasting. It's probably worth noting that a coffee is still considered 'a fresh coffee' 2 weeks after the roast date. It's not lettuce.
As for the effect of processing on perceived freshness, differently processed coffees will 'open up' and taste best at different periods after roasting. In our experience, washed coffees tend to taste best between 6-14 days after roasting; natural or anaerobic coffees tend to take a bit longer, and reach their flavour peak anywhere between 10 and 25 days after roasting.
Does 'Fresh' coffee taste best?
It does, if we consider 'Fresh' being coffee that is less than 1 month old - if you're waiting weeks or months to open and drink your coffee, chances are it will be stale and lack intensity of flavour. In all cases, we recommend waiting at least five days for the 'fresh coffee' to degas the CO2, as it will taste much better.
Not too long ago, companies like Starbucks really pushed the notion that 'the fresher the better' because the norm back then was to drink really old coffee from a tin (and they wanted to create a market for it). Times have changed and that notion really needs to evolve too.
Explain what you think 'Tastes best' if you can..?
Honest flavour. A coffee should be honest to you and be truthful, expressing itself as honestly as possible. This means that there shouldn't be 'roasty' flavours, CO2 covering any inherent traits, or any green coffee flavours from under-developing the roast. It should taste like the best version of itself and that is achieved by excellent farming and processing, great roasting knowledge, the coffee resting of coffee and then finally correct brewing.
How does 'Freshness' affect the cup profile?
Over time florality and aromatic compounds vanish and the coffee becomes very flat. Much like the other end of the timeline where the coffee is 'sparkly' from the CO2, coffee that is too old has no sparkling and vibrancy. It becomes flat and lifeless. The acidity and sweetness of a coffee become a lot less intense and really make for an unexciting cup of coffee.
Are there any secrets to storing coffee to help with freshness?
There are many ways to store your coffee in order to maintain the freshness and prevent it from ageing quicker than it should. Always store your coffee in a dry, airtight environment (or one with reduced air, like a closed coffee bag or container) away from moisture - despite what you might have been told, the fridge is no place for coffee beans, as the moisture can cause ageing and mould.
If you want to store your coffee long term (and prevent ageing almost entirely), try freezing it in a sealed container. Freezing single doses of coffee (19-22g at a time) is being popular in specialty coffee venues across the world, as it allows baristas to halt the ageing of the coffee at the perfect time when it is tasting best. Frozen coffee grinds also generally taste better, brew better and last longer when it comes to the vibrancy of flavour.