Frequently Asked Questions about Coffee

Espresso Coffee

Why does my coffee taste bitter, astringent or harsh?

Your coffee is probably over-extracted. Try making your grind coarser and reducing your shot time. Your yield might also be too long so try stopping your shot earlier. We are looking for sweetness, balance and an even extraction. Dirty espresso machines can also taint the flavour of your coffee so make sure to clean it regularly.

Why does my coffee taste weak, salty or sour?

Your coffee is probably under-extracted. Try making your grind finer and increasing your shot time. Try to keep a brew ratio of 1:2 for a more balanced flavour in your coffee. Channelling could also be a cause so keep refining your technique and make sure you are evenly distributing your coffee.

I am generally not happy with how my coffee is tasting

Try a different coffee that is fresh and locally roasted. Use coffee between 7-30 days after roasting and avoid a best-before date as that can be ambiguous. It could also be your grinder. The grinder is just as important as your coffee machine and getting a good quality one will significantly improve your coffee quality.

What is distribution and does it matter?

Distribution is the process of evening out your ground coffee before tamping and pulling a shot of espresso. Even distribution is a key step in achieving balanced and well-extracted espresso coffee. Uneven distribution along with gaps and cracks in your espresso puck will result in a channelled shot, giving you a watery and bitter-tasting coffee.

Are distribution tools worth it?

Brewing well-balanced and tasty espresso is certainly achievable with good technique, delicious coffee, a good grinder, and an espresso machine without the need for additional tools. Distribution tools like the Nucleus Coffee Distributor (NCD) and the WDT tool will help make your espresso-making process easier but are not essential to making good coffee.

How do I get nice crema in my espresso?

Crema in espresso is mostly Carbon Dioxide trapped in very fine and small bubbles. Ensuring you have distributed and tamped evenly using freshly roasted coffee will result in a nice healthy-looking crema. Lighter roasted coffee will often produce a lighter-coloured and thinner crema, but this does not indicate a lower quality coffee or a poorly extracted shot.

How much do I fill my filter basket?

It is best to stick fairly close to the recommended basket size you are using. Eg. if you are using an 18g basket, use an 18g dose ±1g. Due to limited space, over-filling your basket will result in a harder time locking in your portafilter without disturbing the coffee puck. Underfilling your basket is not as big a problem, but will result in a messier puck after extraction and a higher risk of channelling.

Why do my shot times keep changing?

There are numerous variables that can affect shot times. Assuming your espresso preparation technique is consistent, the cause for a lot of variation in shot times often comes down to fluctuations in temperature, humidity, and the coffee you are using. In most cafes, the most common reason shot times fluctuate is grinder temperature. As a cafe goes through busier and quieter periods throughout the day, the burrs in the grinder heat up and cool down as well, resulting in changes to the particle sizes of the coffee coming out of that grinder. This is why it is important to make small changes to your grind setting throughout the day to stay as close to your target shot time as possible.

 
Tamping an espresso coffee
 
 

Milk and Latte Art

Why is my milk bubbly?

You probably added air into your milk too late in the steaming process.

Make sure you add your froth as early as possible and leave plenty of time to texturise/spin your milk. Alternatively, your steam wand position and height could be incorrect. You want to make sure any bubbles you created are being pulled down into your milk while texturising.

Why is my milk screeching/squealing?

This is a clear sign that your milk is too flat and insufficient air has been added. Positioning your milk jug so the tip of your steam wand is only just under the surface of your milk will help ensure you’re adding air and creating froth nice and early, preventing the screeching sound is the first step in creating creamy and silky frothed milk.

Why are my coffees not pouring well?

Your milk and froth have probably separated. Keep swirling your milk after you finish steaming and make sure it is mixed together from top to bottom. Sometimes pouring the milk into a bigger jug will give you more headspace to swirl and re-integrate your milk and froth before you pour it.

Does milk quality matter?

Absolutely, higher quality milk comes from using specific breeds of a cow (eg. Friesian & Jersey), farming and processing methods (eg. cow diet, organic farming, soil management, biodynamic farming, pasteurisation, homogenised vs non-homogenised, inclusion/exclusion of additives), and seasonality. The best milks have a good balance between proteins, vitamins, and fat content. This results in creamier, sweeter, and almost custard-like milk that pairs very well with good coffee. Some of our favourite Australian producers are Riverina Fresh and Schulz Organic Dairy

Why does my milk seem to bubble up before pouring during certain times of the year?

The flavour of milk from most dairy farms changes throughout the year due to seasonal changes. This primarily comes down to changes in the cows’ diet during big shifts in temperature during a change of season. This is why during certain periods of the year shifts in protein and fat content can cause bubbles to form even after a jug of milk was textured perfectly. It is safe to drink, however, if it is a common occurrence, it could be worth having a conversation with your milk supplier.

Why do bubbles form in my latte if left for a while?

These bubbles are created by the release of carbon dioxide from the coffee. A lot of carbon dioxide is generated during the roasting process, as coffee ages it slowly releases carbon dioxide into the air, this is called degassing. This is why you will often see more bubbles form when using fresher coffee. The same can happen when using lighter-roasted coffee, which has more acidity. This acidity can react slightly with the milk and cause small bubbles to appear in the crema.

Do I need to treat plant-based milk differently?

How a milk froths and heats up will change depending on what milk and brand you are using. Keeping your technique consistent is important, however, varying how much air you are adding to your milk and the temperature you are heating it to according to the type of milk will help give you better results. Generally speaking, most plant-based milks perform better at slightly lower temperatures (55°C) but in a cafe it is better to keep milk temperatures consistent.

How do I prevent soy milk from curdling?

Coffee with higher acidity (or lightly roasted coffee) will cause the soy milk to curdle. Pouring the milk into your espresso faster and more vigorously will help reduce this, however, the easiest way to minimise curdling will be to use a darker roasted coffee. Some soy milk brands also perform better than others with coffee.

 
 

Filter Coffee

What is filter coffee?

This covers most methods of brewing that do not involve an espresso machine. This commonly uses significantly more water resulting in a lower brew ratio. Common examples are Pour Overs, Aeropress, French press, and batch brew.

What is the difference between coffee roasted for filter vs espresso?

Coffee for espresso is often roasted darker to create more body and to reduce the acidity often present in lighter roasts, making for a more balanced cup of espresso. Coffee for filter is often roasted lighter to highlight the natural characteristics of the coffee, roasting lighter also helps reduce the bitterness and dryness that can come with more developed roasts. This bitterness is often more pronounced when brewing filter coffee due to the longer extraction times compared to espresso. That being said, there are no real rules with using dark or light roasted coffee for either brew method and a lot of it comes down to personal preference, with some roasters opting for ‘omni’ roast profiles, blurring the lines between coffees roasted for filter and espresso.

What are the different kinds of filter brewing?

There are two main methods of brewing filter coffee, percolated/drip and immersion. Percolated coffee is where water is dripped or poured over ground coffee, often involving paper filters. Common examples are Pour Overs (Hario V60, Kalita Wave, Kono drippers, Chemex, etc) and batch brew (Moccamaster, Fetco, Marco, etc). Immersion coffee is where ground coffee is completely immersed in water and steeped until the desired extraction is achieved. Common examples are French Press, Aeropress, Syphon, and Cupping.

Why are Pour Overs more expensive in cafes?

Compared to espresso, Pour Overs can be a fairly time-consuming method of brewing in a cafe resulting in a higher cost. The price of a Pour Over is also heavily dependent on the coffee being used, with most cafes opting to showcase higher quality and more expensive coffees using this brew method.

What do I need for a filter coffee setup at home?

Putting together a great filter coffee setup at home is often much cheaper than buying an espresso machine. Brewing kits are often quite reasonably priced, including most Pour Over kits, Aeropress kits, French Press, or even some smaller batch brewers. A gooseneck kettle is also an important part of a good Pour Over setup - electric temperature control kettles are very popular with Bonavita, Brewista, Timemore, and Fellow being the most popular brands for kettles. Finally, a good grinder is essential for brewing well-extracted, balanced filter coffee. There are some great budget options in the hand grinder range with our favourite being the Timemore C3. There are also some great options in the domestic filter grinder market as well, including the Fellow Ode and Option-O Lagom Mini.

 
 

General Coffee Knowledge

How is coffee grown?

Coffee beans are the seeds of coffee cherries grown on trees. Factors such as soil content, temperature, protection from sun exposure, rainfall, and altitude all contribute to the quality and flavour of the coffee.

How is coffee processed?

A large amount of work must be done to remove the fruit of the coffee cherry and dry the seed to prepare for shipping and roasting. There are three main processing methods:

Dry/Natural Process - This involves drying coffee cherries whole in the sun before removing the seed using mechanical methods.

Washed Process - This involves removing the fruit from coffee cherries with water and mechanical methods before drying the coffee seeds in the sun.

Honey Process - Also known as semi-washed or pulped natural. This involves removing the pulp and skin of the fruit of the coffee cherry but leaving the inner layer known as the mucilage intact before drying. This is somewhere between the natural and washed processing methods. No actual honey is involved.

What is fermentation and how does it affect coffee?

Fermentation is a metabolic chemical process where microbes break down substances -mostly sugar- into alcohol or acid. Controlling and experimenting with fermentation is one of the latest trends in coffee processing.

This is quite a polarising process, some enthusiasts enjoy the interesting flavours achieved through fermenting coffee while some prefer more ’traditional’ processing methods, often criticising heavily processed coffee for tasting somewhat ‘artificial’. When executed well, fermentation can help accentuate the sweeter and fruitier notes in a coffee. However over-fermented coffee will often lead to losses in desirable natural characteristics of the coffee and results in a ‘chemical’ flavour in the cup.

How is green coffee bought and sold?

Unfortunately, the global trade of coffee has had a long history and association with colonialism and exploitation, with a lot of these practices still persisting to this day. The best specialty coffee businesses aim for more transparency and fairness in how their coffee is sourced, with a direct-trade relationship between roaster and producer becoming increasingly popular to create a situation mutually beneficial for both parties. Most specialty roasters tend to source their coffee from green coffee merchants who ideally buy directly from producers, but quite often buy from other merchants usually based in the countries of origin.

There are also a number of certification systems such as Fairtrade attempting to regulate coffee quality, sustainability, and fairness with mixed levels of success. James Hoffmann has an excellent video on YouTube exploring the complexities of coffee certifications. Most specialty coffee businesses tend to pay little attention to certification with the exception of organic coffee, with companies like Dukes Coffee Roasters committing to only sourcing organic coffee in an effort to utilise more environmentally sustainable farming practices. More information on this can be found on their website.

How does roasting affect coffee?

Simply put, roasting coffee is applying heat to raw green coffee seeds to produce flavour and aroma when beans are ground and brewed with water. Coffee roasting is a complex process involving a range of chemical reactions but is often characterised into three main categories: light, medium, and dark. In specialty coffee, we often work with light to medium roast profiles to highlight the natural characteristics of coffee.

Generally speaking, the lighter a coffee is roasted the more acidity is retained. The darker you roast the more the sugars in the coffee are caramelised, we also see increased Maillard reactions leading to more perceived sweetness and bitterness. With even darker roasts, we see more carbonisation and the breakdown of more organic compounds resulting in loss of sweetness and aroma, and an increase in bitterness and dryness. Personal preference plays a large role in how people like their coffee roasted with pros and cons associated with each roasting style.

What is that animal poo coffee and is it good?

We get asked this question a lot! Probably from a mix of pop culture and the sheer absurdity of it. Unfortunately, this style of coffee - more commonly known as Kopi Luwak is a terrible and unethical way to drink coffee. What started off as a cultural and traditional way of drinking coffee in Indonesia has now become a commoditised product. For starters, there is no way an animal (most often a Civet cat) that eats, digests and expels the coffee will do a better job than hard-working farmers producing high-quality coffee. So there is no way to justify that price and claim it produces a good coffee. On top of that, people are now exploiting these animals and cage-farming them to sell their coffee at a higher price. Our opinion… don’t do it!

 
tasting coffee
 

Specialty Coffee Industry

How much do baristas get paid?

Pay rate varies depending on age, level of experience, and the individual cafe. Most businesses start with the industry award rate. For the best and most up-to-date information, please refer to the Fair Work website.

Why is coffee getting more expensive?

The main driver of increasing coffee prices are the effects climate change are having on growing coffee and the rising cost of global transport logistics. Producing high-quality specialty coffee is not an easy or cheap process, with painstaking attention to detail being paid at the farm, processing facilities, storage and transport, roaster, and cafe.

How difficult is it to start and run a coffee business?

Between how saturated the cafe market is in Melbourne and all the challenges that come with running a business, operating a cafe can be very challenging. A strong and realistic understanding of how the industry works, a hands-on approach to day-to-day operation, and a strong focus on good customer service are just a small number of aspects essential to operating a successful cafe.

 

For definitions on common terms used in the coffee industry, please refer to our glossary.