Cold brew is exactly what it sounds like: Coffee that is brewed with cold water instead of hot water. To be clear, you cannot simply run cold water through coffee grounds and end up with a delicious cup of coffee. The heat of the water extracts the flavor from the coffee grounds and running cold water through at the same pace would make for a weak cup of coffee so the process must be adjusted.
But first, a little history
Like many things, the origins of cold brewed coffee is murky and uncertain. What we know with certainty is that Dutch traders of the south Pacific would travel with a concentrated extracted coffee and drink it cold. Some claim that they brewed it cold, but I have not found evidence to confirm or deny the claim.
The Dutch brought their room temperature coffee to Japan who already had practice in cold brewing techniques due to using the method for tea. The Japanese either originated the Kyoto-style or adopted it and renamed it. Either way, what we know now as the Kyoto-style cold brew is the tower pictured in this article.
Kyoto-style cold brew
Iced water is placed in the top vessel. There is a valve at the bottom of the vessel that allows one to control the rate of drip into the coffee grounds. As the water slowly makes it way through the grounds, it picks up the flavor and then finds its way into the bottom, collection vessel. This method is a very attractive approach and the tower is quite the conversation starter.
Batch brewing
Another, more efficient method is placing the water and coffee grounds in the same vessel and allowing them to interact for an extended period of time, usually in a refrigerated environment. Similar to steeping tea. At the end of the time, removing the grounds and you are left with a delicious batch of cold brew. This method is more effective at brewing larger quantities.
Time not heat
Both methods take time. Eight to sixteen hours to be exact. You cannot simply pour cold water over coffee and expect a delicious beverage. Because you do not have the advantage of heat to extract the coffee flavor, you use time to achieve the same result, but do not expect the same flavor only colder.
Cold brew coffee is a much different drink and as long as you enjoy a cold coffee-flavored beverage it is better. Cooling a hot-brewed coffee will not taste as good as cold brew in part because the heat continues to work on the coffee even when it is removed from the grounds. Room temp hot-brewed coffee tastes stale. Cold brew has a delicious, full-bodied flavor that is less acidic and a bit more caffeinated.
Difference between iced coffee and cold brew
Iced coffee is a hot-brewed coffee poured over ice. The ice melts, of course. The result is a watered-down version of the coffee. Because the cold brew begins as a cold drink, even when it is served with ice it is not diluted. And you have the added advantage of the cold brew process which, as stated earlier results in a more complex and (some might say) more delicious beverage.
Sound interesting?
Come on by and have taste. If you are uncertain, we will happily give you a sample.