8 Factors That Influence The Quality of Coffee

Whether you’re a hotelier, barista, café owner or coffee-lover at home, we’re all in the pursuit of the perfect coffee. However, what things need to be taken into consideration when trying to create the perfect coffee? It’s certainly not as simple as just buying high quality coffee beans. 

From coffee grind to machine cleanliness, we walk you through the factors influencing the quality of your coffee.

The origin of the coffee bean

It’s pretty common knowledge in the coffee community that coffees with different origins will have different flavors. Ever notice how you prefer that Kenyan Arariba over, for instance, a Guatemalan Arabica? 

The differences in flavor associated with origin come down to the locations unique terroir. Whilst this term is more commonly used in the wine industry, it’s just as relevant for the coffee producing industry. Terroir relates to the unique environmental factors present where that coffee is grown and produced. 

These environmental factors may be soil, altitude, wind, precipitation or topography. These factors play a vital role in determining coffee plant health, resilience, maturation and caffeine production - coming together to create a unique fusion of flavors. 

Coffee bean variety

Similarly to coffee origin, coffee variety has a major impact on the flavor of your coffee. Each coffee bean variety has its own unique flavors thanks to their individual growing conditions. 

There are three main coffee bean varieties - Arabica, Robusta and Liberica. Arabica and Robusta are by far the most common, with 98% of all coffee worldwide originating from these two bean varieties. Arabica is the most popular of the two, with 100’s of sub-varieties with their own distinctive flavors and aromas. 

Coffee bean freshness

If you’re buying bags of pre-ground coffee, you’re doing it wrong. Instead, you need to be starting with fresh, whole coffee beans. 

Coffee reaches its peak flavor just days after it has been roasted and should be consumed within a month of its roast date. Without question though, coffee is best when used within days of being roasted. If you can, try and source fresh coffee beans from local coffee shops or from local roasters - this is the surest way of getting the freshest coffee beans. 

If you’re buying from supermarkets, avoid coffee beans stored in large tubes. Oxygen and bright light infiltrate these containers easily, diminishing the flavor and freshness of the coffee beans inside. Instead, look for vacuum-sealed bags.

Type of roast

Roast profile has a significant impact on the flavor of your coffee, but the differences between light, medium and dark roasts aren’t as simple as color. 

As coffee beans are heated up during the roasting process (hence the name), their color becomes darker as they lose moisture and their oils are secreted to their surface. 

Light roasted coffees are light brown in color, with a light bright body and no surface oil on the beans. Light roast coffees generally have a sharper acidity compared to their darker counterparts, however, retain fuller flavors of origin. 

On the contrary, dark roasted coffees are often dark brown in color, the darkest of the roasts. Due to the secretion of oil in the roasting process, they are often shiny instead of matte. Unlike light roast coffee which preserves the flavors of origin, a dark roast’s origin flavors tend to be overpowered by the flavors present during the roasting process. The coffee will generally have a bitter, smoky or even burnt taste and contrary to popular belief, the level of caffeine is substantially decreased. 

Coffee grind freshness and size

It’s widely agreed in the serious coffee circle that coffee begins to lose its flavour just 30 minutes after being ground. For this reason, as any barista will tell you, it’s best to grind just before brewing a coffee. This will ensure you get the best flavor out of your coffee beans. 

Consistency and grind size will impact the flavor of your coffee, so it’s important that you’re accurate with your grinder. Too coarse a grind and your coffee will be weak. Grind too fine and you’ll over-extract the coffee and it will become bitter. 

For use at home, we recommend a manual hand mill. These grinders are generally the cheapest available but allow for an accurate grind. Blade grinders are available, but are more expensive and often result in inconsistent grind size, leading to a bitter taste. 

Water quality

The quality of the water you use is an often overlooked element of brewing coffee, despite being an important one. Using hard water will result in the water not bonding correctly with the coffee particulates, leading to a weak coffee. Hard water, due to the minerals that can be found in it, can also result in limescale buildups in your coffee maker. 

Serious coffee lovers insist on using either bottled spring water or carbon filters on their taps. Don’t use distilled water, as a lack of minerals is just as harmful as too many. 

To determine whether you have hard or soft tap water where you live, which in turn will determine whether you need to look into using bottled water or a filter, reference your local water providers website.  

Temperature

Water that is too hot can “burn” coffee, extracting unwanted compounds, making the coffee bitter. Most baristas will brew coffee at 195°F-205°F/ 90.5°C-96°C. We find that when the temperature creeps up past 96°C, the texture can become a little powdery, and when it’s at the lower range it’s not quite sweet enough. Which means the sweet spot – for our palettes, at least – is at around or just over 94°C/201°F. 

Once brewed, drink your coffee within 30 minutes. Don’t let coffee sit in a brewer all day long. Make it as you need it, which will ensure freshness and a perfect coffee every time. 

Brewing equipment cleanliness

Make sure to routinely clean your storage containers and grinders every week or so to remove any oily buildup. For your coffee machine, run a solution of vinegar through it every month to remove any limescale buildups, making sure to rinse thoroughly before reuse. 

The perfect coffee

Taking these factors into careful consideration when making coffee will ensure you produce a great cup of coffee every time. However, whilst this list is comprehensive, it is by no means exhaustive. 

The beauty of coffee is that it’s flavors can be enhanced in a number of ways - with only the most important being detailed in this article. Other factors, such as coffee bean storage and harvesting procedure will also have an influence on the quality of your coffee.