Roasting coffee for different applications

There is a virtual "Valley of Death" - between the differing disciplines of roasting coffee beans for milk-based coffee brews versus the purist espresso.

In Australia, around 90% of espresso-based coffees - whether they are prepared in the cafe, home or an office coffee machine are for milk-based beverages.

The cappuccino/latte/flat white has dominated the fresh coffee bean landscape for many years and it's unlikely to reduce in popularity.

Milk-based espresso is the majority target to aim for mass appeal (and commercial success) with most Australian coffee roasters taking a simplistic approach to focus their blend development and roast profiles towards a basic, one-dimensional objective - make it taste good in milk.

Milk applies two dominant influences upon espresso coffee - the alkaline in the milk affects the PH balance of the beverage (softening acids) and a well-prepared, textured milk will also sweeten and in most cases will chocolat-ize (makes it more chocolate) the espresso coffee - in other words, textured milk (heated and stretched) will enhance the chocolate notes in many coffees and provide some sweetness to balance out any roughness in the espresso.

Most cafe style coffees in Australia are roasted with higher acid levels so that when milk is added it will balance, or "cut through". Cut through is an often misused term - sometimes it is flavor (so that the coffee does not taste so milky, other times it is referred to as acid, which is the more technically correct meaning).

Higher acid from cafe-style coffee beans can be unpleasant to the non-milk espresso drinker - cafe style coffee beans are typically roasted darker and this darker roast depth brings taints that are evident in the espresso cup.

Cafe style coffees may also have a baked attribute or experience sourness that is not very pleasant if the barista has not attempted to compensate via extraction methods of grind, dose and temperature.

Each night I have a list of up to 20 different single origin coffees to roast. I tend to start with the softer and more natural processes coffees and select a Brazil Cambara Yellow Bourbon Natural specialty grade bean.

How do I approach this Brazil natural coffee bean for the roast ?

I can take it right into the perfect medium zone to generate some intense caramel, chocolate, hazelnut notes for a perfect milk-based espresso, or do I run it light and short to retain all the fruits and complexity for a pure espresso delight...........therein lies the paradox - roast for the majority or roast for the bean's natural characteristics ?.

This thought runs through my mind 100+ times a week - do we showcase exceptional espresso or perfect milk-based with rich flavor.........it's a tough call.

Out there on the internet, there is an often repeated mantra - "if you perfect the espresso, the added milk will not materially change the dynamic and will only improve the cup".

But I disagree with this very simplistic urban myth (which has unfortunately grown long legs).

There are a few cafes in Melbourne who use this "perfect espresso" comment as their own marketing ploy - it is their way of trying to create a differentiated position in the cafe market.

In some cases, if I roast a coffee bean for perfect espresso, it can be lost in milk - lacking body, flavor, finish, etc.

Similarly, if I roast the coffee beans for milk, the espresso may be compromised by being either roasty if a bit dark, acidic if too light, baked or sour if under-developed - depending upon the bean and the roast profile.

Some coffee beans are able to bridge the milk and espresso Valley of Death, whereas other coffee beans will not - no matter how many different tweaks you may do to the roast profile or engineer the espresso shot as a barista.

As a sidebar, for 3 years I had been silently unhappy with espresso-only outcomes for some of our coffees.

Why ?

Because of the reasons I have noted above - we roast to satisfy the majority of our coffee lovers who add milk to their espresso and who may possess only limited barista skills or equipment - so our roasted coffee beans need to have rich flavor and a long, persistent finish without the coffee tasting like a strawberry milkshake filled with artificial sweeteners........

AND ...........

It can become extremely confusing if we were to offer a particular coffee in 2 different roast profile options - roasted for milk or roasted for espresso. You can guarantee someone will pick the wrong profile option and end up being disappointed.

Recently, some of the world's most respected coffee bean roasters have also confessed to having arrived at similar unhappy destinations - Tim Wendelboe and a few US specialty coffee roasters admitted similar feelings about their own espresso offerings.

It is ironic that I have also been going through similar reflections in regard to espresso extractions for some time.

Our performance in the coffee roasting competitions - RAS International May 2013 and the Golden Bean October 2013 - were a bit of a slap in the face.

OK, Bronze medals are not something to be ashamed about, but for both events we did not submit coffees that were representative of what have been typically generated each week from our roastery over the years for specialty cafes - custom roasted coffees that work exceptionally well as espresso.

I had a choice to make - enter our normal roast profiles for our everyday coffee bean products or the specialty custom roast profiles.

Just like the golfer who goes out during the week and scores a 4-under card, we know the performance of our coffees each week are better than our competition results.

During September and October 2013, we conducted a series of experiments in conjunction some of the specialty cafes we supply in Melbourne.

The objective of the exercise was to identify which of the 2 different coffee roasting plants we have installed in our Roastery are best suited to pure espresso coffee.

The exercise also gave us the opportunity to review our overall strategy to roasting profiles for espresso - the shape of the curve, rate of rise, final temp and duration.

What we discovered is that one roasting plant works better for espresso than the other.

The development of re-engineered espresso roast profiles results in different acid developments and we are carefully integrating these optimized profiles across some of our coffees to provide improved cup balance.

In late 2014, we purchased another roasting platform. The brief for that large capital outlay included a criteria for how espresso coffee tasted from the new platform.

During the 2nd half of 2015, we successfully installed the new platform and the results of espresso from the new platform exceeded our expectations.

Whilst espresso remains the minority, we can fully respect and appreciate the concept of perfecting this category due to it's vital importance for our on-going development and improvement.