We’re adding a few experts to our roster of writers – true guns of coffee, wine and craft beer. We kick off things with barista, cafe owner and coffee trainer Darren Silverman as he answers the top 10 most frequently asked questions he is most often asked about good coffee.
My wife Jackie and I run Black Velvet Coffee in Melbourne where we source, roast and make coffee, but we also conduct training sessions for people who want to make the best coffee they can.
Many of those who come to the courses, from budding baristas to home aficionados, share a dual purpose: not only do they want to make good, fresh coffee they want an understanding of an industry that can now seem filled with scientists and jargon rather than baristas.
Before my life at Black Velvet I spent three years working for a large coffee company and became their training specialist. The world of coffee is an endlessly fascinating journey of learning, yet while sharing the knowledge I’ve so far brewed I’m often asked the same relevant questions.
Below are the top 10 coffee questions and their answers.
1. What exactly is an espresso?
An espresso, not expresso, is the term used for a single shot of coffee. Espresso is made when hot water is forced, under pressure, through coffee to extract its oils. While this is some people’s preferred way of drinking coffee, baristas also use a shot of espresso to make standard milk-based coffee.
An espresso should be between 25-30ml and take around 30 seconds to extract: if it is poured too fast it is ‘under extracted’ and leaves a sour taste on the sides of your tongue; if it takes too long to pour it is ‘over extracted’ and burnt, leaving you with a bitter taste.
2. What’s the difference between a latte and a flat white?
Not a lot. Twenty years ago people were drinking cappuccinos and flat whites until the latte became the new ‘in thing’. It was served in a glass with a small head of foam. Then ordering was based on personal preference: did you want your coffee in a cup or a glass?
But is there really a difference between lattes and flat whites? Maybe there is a little less foam on a flat white. Maybe. In a takeaway cup there is little, if any, difference. In cafés any difference will come from the respective volumes of the cup or glass: a latte glass is usually around 220ml while in many cafés a flat white is served in a slightly bigger or slightly smaller cup (between 170-240ml).
With an espresso shot being the same, the coffee to milk ratio is therefore different: the flat white can appear a little weaker or stronger than the latte depending on the size of the cup.
3. Does it matter which milk I use?
Some milks enhance the flavour of your coffee, others detract from it. For best results always try and use milk that contains around 3.5gm of fat per 100ml. Varieties of milk that claim the same great taste with less fat (often) have sugar added and sometimes even milk powder. Either way, both negatively affect the taste of your coffee. Good cafés consider their milk choice as important as their coffee.
4. Why should coffee not be served too hot?
Ideally the milk for your coffee should be steamed to 65-70 degrees – I know this sounds a little technical but there is a reason for it.
When milk exceeds 70 degrees it rapidly begins to break down. If it gets hotter or is boiled it loses its texture and begins to sour. This affects the flavour of your coffee.
It makes no difference at all if you take time to drink your coffee. The chemical change in the milk has still occurred and it will, even though cooled, have little texture and taste sour.
5. What is the difference between a Blend and Single Origin coffee?
A blend combines two, three and sometimes four coffees from different origins around the world. They are blended to balance the flavours for all parts of the palate. A blend is used for all standard coffees and designed so the flavour stays true even after milk is added.
Single origin coffee is sourced from just one geographical region of a country and is usually consumed black to enjoy the individual characteristics of coffee from a particular area.
6. Why is freshly roasted coffee better than pre-packaged coffee?
Most people wouldn’t buy meat, milk, fruit and vegetables, or bread unless they’re fresh. Some coffee is fresh, some coffee isn’t.
Coffee is at its absolute best between 7-14 days and no longer than 3-4 weeks after roasting. Reputable coffee roasters always write the roast date on the bag. If the bag has a ‘best before’ or ‘use-by date’ rather than a ‘roast date’ it’s because whoever packaged the coffee would rather you didn’t know when it was roasted. Coffee is a natural product. It grows on a tree and has a shelf life.
7. Does vacuum-sealed equal fresh?
Immediately after roasting coffee emits carbon dioxide and the de-gassing process takes up to 10 days to complete. It can be argued that it is only possible for the vacuum-sealed packet to hold its seal after the de-gassing process is virtually complete. During this time the coffee has already begun to go stale.
8. How long does fresh coffee last?
Raw coffee, if stored in an ambient temperature with little or no humidity, can last for up to a year before its quality changes.
Roasted coffee has a much shorter life and is at its best up to four weeks after roasting: air, light and heat reduce its aromatic qualities. Roasted coffee is also porous and takes on the aromas and flavours it is exposed to. People sometimes claim their coffee has taken on a strange flavour while stored in the fridge next to fresh foods.
9. Fridge or cupboard: How do I best store my coffee?
The temperature of your storage area will have a dramatic effect on the shelf life of your coffee: the warmer the temperature, the shorter the shelf life.
Cooler temperatures are okay although I’ve consistently found the extracted flavours to be better if my coffee is stored at room temperature. There is nothing wrong with keeping your coffee in the fridge but try to remove it so it can reach room temperature before use.
I think it is best to keep roasted coffee in an airtight containeraway from natural light: in a dark cupboard works best for me.
10. What else can I do to taste the true flavours in my coffee?
Since the shelf life of your coffee will reduce much faster after it has been ground, if possible grind your coffee as you use it. If you buy pre-ground coffee try buying smaller quantities.
If you have any further questions, hit us up in the comments section below. Otherwise, pay Darren a visit at:
Black Velvet Espresso
136 Exhibition Street, Melbourne 3000