This can be a confusing and challenging topic for many and has even caused arguments among friends of mine.
Iced coffee has been a staple in coffee houses in Europe and particularly the States for the last 100 years or so. Cold brew, however, has only started gaining popularity in Western Europe and the States in the last 20 years or so, and only dramatically in the last 10 years. Is it just another name for Iced Coffee? Why do certain coffee drinkers swear by it? We are obviously fans of Cold Brew on this site, but we concede that there can be a time and place for both drinks. Today we are going to examine both beverages, highlight the differences as well as the different advantages and disadvantages of both.
What Is the Difference Between Iced Coffee and Cold Brew?
As most of you probably know, cold brew is a tasty beverage that is brewed completely cold, as the name suggests. There is no time in a Cold brew coffee’s life when it needs to be heated.
Cold brewing has actually been a method of brewing coffee for hundreds of years. It was originally practiced in Japan. It then spread throughout Asia and different methods of cold brewing were developed using brewing practices introduced to Asia by the Dutch.
Iced Coffee, on the other hand, is coffee that is brewed hot and then cooled down using ice, water, cream, ice cream or simply by putting it in the fridge.
Cooling down coffee in this way is also not a new practice, and was an obvious progression for coffee drinking, as hot drinks are not nearly as appealing in the summer and everyone wants their brew to be cold and refreshing when the weather is hotter.
Iced coffee enjoys huge popularity among the general public, to the extent that coffee chains such as Starbucks are associated with their iced coffees more than with their hot coffee.
Iced coffee is normally served sweetened and can almost be described as a desert, depending on how it is prepared.
Coffee and heat
The question is: why did our ancestors start heating coffee in the first place? Isn’t it strange that brewing coffee beans hot has been the standard way of brewing coffee?
Well, the answer is simple. Heat is energy, and when we add heat to coffee it multiples everything about the brewing process. More energy equals more chemical reaction. This is very useful for coffee, as it means we can brew in minutes as opposed to hours or days.
The brewing time isn’t the only thing that is affected by adding heat to coffee beans. Every part of the brewing process is multiplied, including extraction, so much more of everything is extracted from the coffee bean. This means acid, oil and even caffeine. A hot coffee, and by extension an iced coffee, will contain more acidic and oily properties than a cold brew.
This also means, contrary to popular belief, that, per ounce, hot brewed coffee has more caffeine content than coffee cold brewed. However, a standard cup of cold brew normally has more caffeine in it than a cup of iced coffee. I’ll explain why this is a little later on in the article.
Is Cold Brew Better than Iced Coffee?
From the previous paragraph it sounds like heating coffee is the far superior method for brewing coffee. Why bother cold brewing at all? It takes much longer after all.
Well, it really comes down to two things – oxidation and dilution.
Heat also has another effect on coffee beans. Apart from speeding up and magnifying the whole brewing process, heat also serves to make coffee a lot more volatile. Once coffee is heated, it is then immediately prone to oxidation.
What Is Oxidation?
Oxidation is the same thing that happens to the half of the banana you put in the fridge that goes brown unless you cover it with plastic wrap. It is also the reason that metal gathers rust over time. Oxidation is basically a chemical reaction that happens when certain substances are exposed to air.
What does this mean for coffee?
Coffee is prone to oxidation throughout the whole brewing process, as soon as it is heated. This means that coffee beans that are roasted are prone to oxidation and need to be stored in airtight containers or bags.
The same goes for the brewing process. When hot water is added to the ground coffee, the coffee starts to go stale when it comes in contact with the air. Have you noticed that coffee goes bitter if you don’t drink it straight away? Think of a cold espresso. This is oxidation and is a big reason why iced coffee isn’t an optimum beverage.
Iced Coffee and Sugar
If fresh, hot coffee is used straight away to make iced coffee, the quality is still going to degrade and it is still going to taste bitter. Indeed, many coffee places will use espresso shots that have been sitting by the machine for some time, as they figure it is going to be cooled anyway, so what’s the difference?
The net result of this is that we need to sweeten iced coffee for it to be nice. Hence, the culture of drinking iced coffee with lots of sugar etc. We all know that this isn’t ideal for health. A standard, plain Frappuccino from Starbucks contains almost 70 grams of sugar!
Oxidation and Cold Brew
Miraculously, when coffee is cold brewed it is not prone to oxidation and is much more stable. It doesn’t degrade when it comes into contact with the air and is therefore much more naturally sweet. It is not necessary to sweeten cold brew in order to make it palatable.
The other reason that cold brewing is superior to hot brewing and then cooling the coffee is dilution. Due to the fact that we need to add things such as ice or cold milk to hot coffee in order to cool it down and make it iced coffee, we are by default diluting the coffee recipe.
Dilution means that we are never going to have a truly balanced tasting iced coffee and is another reason that we need to sweeten iced coffee in order for it to taste nice.
Advantages of Iced Coffee and Cold Brew
In the last section, I was raining a little hard on Iced Coffee’s parade. I have had many a creamy, delicious iced coffee in my time after all.
Iced coffee has several advantages over cold brew. Firstly, it is much quicker to prepare. Taking into account brewing and preparation time, most iced coffees won’t take longer than 5 minutes to prepare. Cold brew, on the other hand, needs at least 12 hours to brew, and ideally longer. This takes planning and is not always practical for a busy person or indeed a busy coffee shop.
Also, as I mentioned, iced coffee will have more of the traditional coffee tastes that we are familiar with, such as brightness and acidity. This is an advantage for some people who are expecting a traditional coffee taste profile.
We touched on the main advantage of cold brew in the previous section. Namely, it is a more balanced, better extracted, more naturally sweet tasting drink. We don’t need to add ingredients or doctor a cold brew. It can be taken as you would drink your regular joe ie. with a bit of cream and sugar if that is your taste, or else black and straight up.
The other great thing about cold brew is that is incredibly easy and inexpensive to do. It doesn’t require any machinery (such as an espresso machine) or barista technique. Ground coffee is literally left to sit in room temperature or cold water for at least 12 hours, then filtered and served.
Tasting notes of cold Brew
Compared to the brighter, more acidic profile of iced coffee, cold brew will have a smoother, more chocolatey taste. The lack of acid is kinder on sensitive stomachs. It will also damage and stain your teeth less.
Caffeine Content – Iced Coffee vs Cold Brew
Although hot coffee has more caffeine than cold brewed coffee per weight, cold brew generally contains more caffeine than iced coffee.
As I already pointed out, iced coffee is diluted by the other ingredients added, so the caffeine content is also going to be diluted.
On the other hand, cold brew is generally brewed as a caffeine concentrate, with a high coffee to water ratio. This is due to the long brewing process. It would be entirely impractical to brew cold brew coffee by the cup. Therefore, it is brewed as a concentrate and water or milk is added before drinking.
In theory, this has the same effect as cold ingredients do on iced coffee. In reality, however, the caffeine concentrate is extremely potent and is generally diluted less than iced coffee is.
Normally, an espresso machine will be set up for hot brewing and the occasional shot will be used for an iced coffee. This means that the recipe is dialled in for hot coffees, and adding the iced coffee ingredients throws the recipe out of balance. The cold brew recipe, however, is calculated to be extra strong and then diluted, so that the end product is a balanced drink.
Different drinks for different occasions
This all comes around to what I pointed out at the start – iced coffee and cold brew are two totally different drinks that are appropriate for different people in different scenarios. Enjoy each one independently and do your best not to compare them, tricky as that might be!