It’s August. Now begins the scramble for the beach and other summer favorites before autumn’s chill rolls in. Although it’s available all year round, our cold brew’s popularity peaks during the warmer months. People show interest in learning how to make this delicious beverage, but the hours the process consumes sound daunting. There’s a solution to that. Good cold brew can be made in 90 minutes, but this finding didn’t come easy. There was plenty of trial and error until we got it right. Here’s the explanation of the C-Bru Greenstreet is known for!
Different coffees are used for cold brew at Greenstreet. We either use single origin, or a 50/50 blend of two different single origins. The Ethiopian Kochere has been a great choice. Tom started cold brewing about three years ago. The first way consisted of mixing coffee grinds on a very coarse grind with water. He used a five gallon bucket, about five gallons of water, and five pounds of coffee. Cold brew brewing equipment can be made out of pretty much any kitchen appliance that can be used for the coffee and water to steep, and as a filter. Tom initially used a cheese cloth held by a rubber band around the rim of the bucket. That method was a nuisance because there were times in which the end fell off. He decided to buy a toddy from toddycafe.com, but has evolved into using different containers but the toddy filters.
Over time, Tom has become familiar with the different tastes that each coffee (single origin or blend) can produce via this method. He realized the Rooster Roast was too tart (or bright in coffee lingo) as a cold brew, so he gravitated towards African and Indonesian coffees. Soon after, he made batches at different steeping times, and temperatures to narrow down the recipes with the best flavor. After a while, with the help of his friend Derrick Smith, he realized that only a handful of hours were necessary. Ninety minutes turned out to do the trick. It yielded an extraction of about 95%, and much less oxygenation which kills the cold brew taste. The combination of experience and science helped Tom confidently proceed with the Ninety Minute Method.
Tom’s friend Derrick Smith, a Drexel University Fellow Graduate Researcher perfected the secret behind the ninety minute cold brew. Every day, he brewed a small batch at work. He took note of different tastes and variables until his batches were consistent. Why did he do this? He did it for fun. Here are some of his conclusions.
1. Grain size didn’t affect the taste, but brew timing and ease of pressing did. Keep in mind, larger grains are easier to press, but they elongate brew times
2. Warm water speeds up the process
3. Room temperature water ( with grinds the size of typical ground coffee at 3 cups per gallon) causes little to no noticeable change in taste after 90 minutes
4. Cold water that has sat in the fridge overnight (2 cups of grinds per gallon) results in a tea-like drink
Here are a handful observations from his “large batches”:
He usually used 3 cups of coffee per gallon; that amount seemed to be over double the strength of regular coffee. He didn’t notice a substantial difference in taste strength between 4 and 5 cups per gallon in an overnight brew at room temperature. Approximately 4 cups per gallon was close to the saturation limit of the water. That strength was too much for him; the amount of caffeine in a 16oz cup gave him a headache. This is coming from a guy who drinks a 32oz cup of regular coffee with no problem! Lastly, a tuna can filter (with multiple holes) worked about twice as efficiently as a flat filter.
There you go! Stop in at 1101 Spruce for a cup or bottle to go. Feeling adventurous? Try making it at home. Just don’t wait until it’s too cold for a cold brew. If you do, hear is some good news: Cold Brew is never hot brewed, you can heat cold brew to have unique coffee experience that may shatter your perception of coffee. Tom would love to hear your cold brew stories or answer any questions you have about the fine elixir. Email Tom @ firstname.lastname@example.org.