Why Blend Coffee Beans?
September 19, 2018

Why Blend Coffee Beans?

Coffee blends are making a comeback.  Once criticised as a vehicle for large commercial coffee roasters to use up leftover coffee beans and combine cheap coffee with more expensive beans to reduce the cost of their offerings, blends are now making a comeback via artisan and speciality roasters because their customers demand flavour profiles that are repeatable and consistent, year round. 

A coffee blend is a mixture of two or more different single origin coffee beans that are mixed together. The idea behind blends is to take the best qualities from different origins and blend them to create a smooth, well-balanced tasting coffee.  Normally, combining the different origin coffees adds greater balance and complexity, while highlighting the best notes of each component coffee.  Another advantage of blends is the fact that they are not as overpowering as single origins.  As a result, they work well as the base for your traditional espresso based drinks, such as lattes and cappuccinos. 

In addition, blends are often more consistent and forgiving than single origins.  This is to do with the fact that you will notice the seasonal variations more in a single origin than you will with a blend.  On many occasions, single origins will only be available for certain periods of the year as they are generally grown in much smaller quantities than beans that are used as bases of blends.  Since qualities like body and flavour can differ markedly between farms, regions and even harvests from the same farms, the only way to ensure consistent flavour is to blend coffees from several different regions in order to minimize the differences among them.

The big challenge with a blend is to try to create a coffee that maintains an all-year-round consistency without losing all of the unique origin flavours. In order to achieve this, a lot of roasters will roast their blends darker (medium or dark roast) in an attempt to be able to achieve a more uniform and consistent taste. The main disadvantage of roasting darker is that you can lose the unique coffee origin flavours and develop more darker and bitter flavours in the coffee. Some people look for these flavours especially in stronger espresso roasts as bitterness is often wrongly associated with the strength of a coffee.

While consistency may be one of the factors considered when specialty and artisan roasters blend coffees, their main goal in blending is to create a specific flavour profile that they expect many customers will enjoy. This is where the artistry of coffee blending lies, in discovering and melding the unique qualities of two or more coffees to create a new coffee that is more than the sum of its parts.  It’s not possible to fully predict what the coffees will taste like when blended, but there are rules of thumb which roasters follow to help remove some of the guess work.

Most coffee roasters use no more than five coffees per blend, with each single origin bean making-up at least 8% of the final product.  Since a single espresso shot uses roughly 17g of coffee, this equates to only 100 beans.  So, if a coffee is much less than 8% of the blend, it really makes a negligible contribution to the coffee flavour.  Roasters choose to set a tone for the flavour of the blend by choosing a single origin which will act as a “base” bean for the coffee.  This normally constitutes between 30% to 40% of the blend.

The choice of base bean will determine where the balance of the coffee flavour lies between the three types of flavour notes:

  1. Low Notes: are the musky, chocolatey, nutty, earthy, caramel, or ashy type flavours detected on the front of the tongue.  Sweet low notes make for a smooth coffee and are popular in blends, referring to the presence of a caramelly flavour in the coffee.  To create a sweeter blend, roasters use coffees that take on browning flavours from the roasting process.  Roasters will use Brazilian, Mexican, or Peruvian single origin beans as a base to achieve sweet low notes.
  2. Middle Notes: or mid-palate, define the body of the coffee during the moment between the first sip and the swallow.  Blends that are dissatisfying during the mid-palate are often called “hollow”, or lacking in body.  To avoid this in a blend, roasters use a juicy bean with plenty of malic acid - think flavour notes of green apple, peach, or stone fruit.  For a blend with strong body, turn to origins such as Colombia, Guatemala, and Costa Rica as the base bean.
  3. High Notes: are the bright, acidic, floral, citrus, or cinnamon type flavors and aromas.  Some single origin coffees which are strong in these high notes can, by themselves, be overpowering.  But, they work very well in blends to give added complexity, through acidity and floral notes.  Kenyan or Ethiopian beans can be used as a base in blends to give strong high notes to the blend.

Most blends combine beans which have low, middle and high notes in order to offer the complexity and balance now valued by coffee drinkers.  But the specific ratio combinations vary significantly, depending on the flavour characteristics suited to the role of the blend.  For example, breakfast blends are often made up of a higher percentage of bright, acidic coffees.  While Italian Blends are made up of beans with earthy notes which hold up under a darker roast and which have hardly any brightness.  

Roasters tend to guard their blend recipes fiercely because their blends provide a point of difference from other coffee roasters.  When trying a coffee from a new roaster, we always recommend starting with its Signature Blend.  These blends normally represent the flavour philosophy of the roaster.  And this is certainly true for Spiller & Tait.  Our Signature Blend combines five single origin beans from around the world, which are medium roasted to achieve a coffee which is smooth, balanced and lacking in bitterness - flavour traits that we believe are valued by the majority of coffee drinkers in the UK.