Hot Days, Cold Brew

Wednesday, 21 August, 2019

Although cold brew has been floating around cafés for a number of years now, the caffeine kick has officially hit the mainstream consciousness as it moves beyond cafes and on to supermarket shelves. 

And the options to get your fix are endless. You can buy it at your local coffee shop, you can find it stocked in many supermarkets (and still more to come in the near future!) or you can brew it at home. And actually, all the options are pretty easy to accomplish. There are of course expert cold brewers at your favourite coffee peddler who have the technique down pat, but you need not be intimidated to try this at home.

As long as you start with good quality beans, use a good ratio of coffee to water (we’ve got a recipe option for you!) and come prepared with a dollop of patience, you’re unlikely to have trouble getting a great cold brew coffee as a result. 

The extended extraction time required to brew this style of coffee means you’re essentially making a coffee concentrate. During the cold-brew process, time replaces heat. Todd Simpson, a chemical engineering graduate of Cornell, who developed the Toddy® Cold Brew System, discovered that high temperature facilitates the release of certain flavour elements. The temperature means that the acidity and bitterness normally associated with coffee are not given the opportunity to appear and sweetness and smooth mouthfeel are enhanced.

The main difference between Cold Brew and Iced Coffee is in the process (which also accounts for the differences in taste). Cold Brew coffee is steeped in cool water at room temperature for at least 12 hours (usually more), before the coarse grounds are filtered out. Without the heat, it takes a long time to extract maximum flavour. Cold Brew coffee tends to be much less bitter than regular coffee because heat is what releases the acidity of the coffee bean oils. The result is a much smoother coffee concentrate that can be mixed with milk or water. 

Iced Coffee is brewed like regular coffee (usually extra strong) and then cooled by pouring over ice. Simple really! At some establishments, you might run the risk of being served this morning’s stale coffee over ice, but the way it’s supposed to be served is immediately over ice after brewing. It’s typically sweetened and may be served with a pinch of cream or milk, and the result is a light, refreshing drink with all the natural aromas of your regular hot coffee.

Because the brewing process for both beverages is so different, the flavours are as well. The brewing temperature impacts the extraction of acids, sugars and oils from the bean, and ultimately, the final cup. Cold Brew is much smoother and milder in flavour than regular coffee – it tastes sweeter and less acidic. This is because less flavour is extracted at a lower temperature.

If mild and sweet are not what you want from your coffee, Iced Coffee preserves all the natural aromas of regular coffee, with a crisp acidity and rich flavour profile. When done right, Iced Coffee retains the intense flavours and complexity of the bean, delivering all the goodness of your regular cup of coffee – just chilled.

A roasted coffee bean contains many compounds that are extracted during the brewing process. Some of those compounds, including certain oils and fatty acids, are soluble only at a high temperature. During the cold brew process, coffee beans are never exposed to high temperature (this only occurs after a rich liquid coffee concentrate has been produced).

Deceptively simple, cold water brewing extracts the delicious flavour compounds (and some of the caffeine) from coffee beans, but leaves behind myriad bitter oils and biting fatty acids, including undesirable elements such as ketones, esters and amides. These are the same bitter acids and fatty oils that surface to the top of your hot cup of coffee, and give hot-brewed coffee that familiar 'bite' (thus the reason that some 8 out of 10 people attempt to soften the acidic taste by adding milk or milk to their coffee).

There are a number of nifty gadgets on the market that make the messiest part of the brewing business, the filtering, much easier. In fact, the Toddy Cold Brewer has been on the market for over 50 years and they’ve got a no-fail filtering system, plus it comes with an awesome airtight carafe for storage. The Hario cold brew bottle is a simple immersive device, you pour the water through the coffee in the filter and that keeps the coffee separate from the water, but still in the water so you don’t even need to worry about filtering at the end, pretty ingenious.

Sales of cold brew coffee at both cafe and in the retail sector have absolutely skyrocketed in the United States over the last couple of years. Allen Leibowitz, a partner in Momentum Coffee in the US, puts it eloquently when he states why its moment has arrived: "I think cold brew finally clicked for a number of reasons. One is the broad spread of specialty coffee. Quality coffee has gone mass market. Take a look at any of the mass market retailers and grocers. It (specialty coffee) is also part of every day conversation, so a 'new' type of coffee cold brew may be more accepted now as people look to broaden their coffee palate."

And South Africa is sure to follow suit soon. The SA summer has been waiting too long for delicious cold brew coffees available everywhere and not just at the best coffee spots.

Now, the real skill comes in during mass production. The Ready To Drink (RTD) market is just waiting to be tapped and the front runners in South Africa are up to the challenge. So who do you need to look out for on the shelves? Some of the cool cats leading the charge are Sea Dog Coffee and Potion Coffee. 

In the next few weeks we'll be exploring both the RTD market and the fun ways you can use cold brew over the coming summer months. 

First up, try our recipe to make your own Cold Brew at Home!

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