Whether you’re a seasoned home barista, or a casual coffee drinker, you’ve likely heard of cold brew. The popular alternative to hot brewed coffee, known for its lower acidity and smoother taste. But what exactly is immersion cold brew, and how does it differ from other cold brew coffee methods?
This article will dive into the heart of immersion cold brewing, exploring its equipment and process and what distinguishes it from comparable techniques. We’ll also reveal its benefits and factors for the perfect batch.
Once you’ve mastered this coffee-making method, you should be all set to dazzle your friends with your newfound knowledge. So, grab your favorite brew and join our electrifying, caffeine-charged adventure.
What Is Immersion Cold Brew?
Immersion cold brewing is a coffee-making method that involves steeping coffee grounds in cold water for an extended period, typically 10 to 24 hours. This process extracts soluble solids in coffee, (flavors), resulting in a smooth, less acidic, and highly concentrated coffee beverage you can serve over ice or mix with milk.
You are probably asking why do we prepend immersion to the name? Well, because this is just one way of preparing cold brew. There are a few other ways to prepare this caffeinated beverage, each with pros and cons. Let’s dive in, and you’ll be an expert in no time.
Coffee is a solution made by dissolving soluble solids in water, giving it flavor and aroma. The rate of dissolution is the speed at which these solids dissolve in the water.
With hot brew, we speed up the dissolution, similarly to how sugar dissolves faster in boiling water than in cold water. Read more here about the Chemistry and Physics behind Cold Brew Coffee.
Because this method is very simple, there are a lot of ways we can prepare it, and people improvise equipment out of common cooking utensils found in the kitchen, including pots and jars.
Most commonly, the equipment used includes:
- French press: A French press is versatile enough to make immersion cold-brew coffee. To use a French press for cold brewing, begin with coarsely grinding your coffee beans, add them to the French press, and pour hot water over the grounds. Next, stir gently to ensure even distribution, then press the plunger down to force water through the coffee grounds into the pot.
- Toddy system is a specialized brewing device consisting of a brewing container with a reusable filter, a decanting carafe, and a rubber stopper. To use the Toddy system, place the stopper and damp filter at the bottom of the brewing container, add coarsely ground coffee and cold water in alternating layers, and let it steep for at least 12 hours. After steeping, remove the rubber stopper, allowing the cold brew concentrate to flow into the carafe.
- Mason jars: Mason jars are a simple, sustainable, affordable option for immersion cold brewing. Begin by adding ground coffee to the jar, pour cold water over the grounds, and stir gently to ensure all grounds are saturated. After which, seal the jar and leave it at room temperature for roughly 12 hours. Finally, strain the coffee through a fine mesh sieve, cheese cloth, or a coffee filter to separate the grounds from the concentrate.
- Any other cold brew system that uses steeping as the extraction method. Toddy is one of the most popular ones, and the oldest on the market. However, the market is more competitive today, and we have an article on the subject here: Best Immersion Cold Brew Coffee Makers Compared. The list includes Oxo, Filtron, Takeya, and Toddy.
We think that our method of making cold brew with a mason jar and a disposable filter bag is the best. It is easy, convenient and cheap.
Primary factors that influence immersion cold brew quality:
- Coffee-to-water ratio: The proportion of coffee grounds to water is crucial for achieving the desired taste and concentration. The typical ratio is 1:4 (1 part coffee to 4 parts water).
- Grind size: A coarse grind is recommended for immersion cold brew, as it allows for slower extraction and prevents over-extraction.
- Brewing time: The steeping duration affects the flavor and strength of the cold brew coffee. While 12 to 24 hours is the standard range, feel free to experiment with shorter or longer steeping times to achieve the desired taste.
- Water quality: Clean water with essential mineral content is key to good-quality cold brew coffee. So, avoid using distilled water.
Immersion Cold Brew vs. Other Popular Cold Brew Methods
In this section, we’ll compare immersion cold brewing with other cold brew methods, discussing the key differences in the brewing process, flavor extraction, and convenience.
Overview of popular cold brew methods
- Japanese-style slow drip: This technique entails gradually dripping cold water onto a bed of coffee grounds, allowing the flavors to be gently extracted and collected in a chamber below. The process takes 6 to 24 hours, depending on the dripping rate.
- Vacuum cold brew: It utilizes negative air pressure to force water through coffee grounds. Using a vacuum cold brewer, you can enjoy your coffee in a time range as short as 30 seconds to as long as 10 minutes.
- Agitation cold brewing: This method expedites cold brewing while producing a rich, smooth coffee concentrate with lower acidity. It relies on the movement of the coffee grounds, typically achieved by stirring or shaking the coffee-water mixture.
Key differences: Brewing process, flavor extraction, and convenience
Immersion cold brew involves steeping coffee grounds in cold water for an extended period, usually 12-24 hours.
In contrast, the Japanese-style slow drip relies on a controlled dripping rate and the brew time is between 3 and 6 hours.
Vacuum cold brew uses pressure changes that lowers the boiling temperature to the room temperature.
Lastly, agitation cold brew utilizes physical agitation to accelerate extraction. The agitation could in the form of spinning the slurry in the brew chamber, or vibrating the slurry with a high frequency wave, which in turn agitates the molecule in the slurry to speed up dissolution.
When done right, immersion cold brewing extracts a full-bodied, robust flavor. All origin notes are muted because of the high extraction rate. Floral and citrusy notes are less dominant because coffee is stronger.
Vacuum cold brew can taste quite differently, depending on the filter, brew time, and grind size. It is my favorite brewing method because it’s so versatile. When extracted longer to get a cold brew concentrate, it delivers a stronger coffee, and extracts much more coffee oils than immersion cold brew. This makes vacuum cold brew the espresso equivalent.
Japanese-style slow drip produces a brighter, aromatic flavor. You will be able to distinguish origin notes for those who enjoy single origin coffees. Slow drip is the equivalent of the pour-over, and immersion is the equivalent of the French press, if you want an analogy with the hot coffee world.
The agitation method has a muddier body, and over extracts a little, compared to other methods. When I brewed coffee using the agitation method, I needed to use a paper filter to strain some of the muddiness.
Immersion cold brew is the most straightforward and accessible method, requiring only a container, coffee grounds, water, and a filter.
The Japanese-style slow drip and vacuum cold brew methods demand specialized equipment and precise control. There is some baby sitting involved, when you need to adjust the dripping rate over the course of a batch.
Agitation cold brew might be a quicker alternative, but it often requires more hands-on involvement. The biggest problem with agitation methods, is that the flavor profile is different. With many agitation devices we get over extracted coffee at the same TDS. In order to avoid over-extraction, many manufacturers adjust the recipe to make a weaker cup, which is equally underwhelming, if not more.
Vacuum is the most convenient method, but vacuum cold brew coffee makers are not cheap, and they are complex appliances that can break, compare to the low tech of a mason jar and a bag for immersion cold brew.
Distinct Qualities of Immersion Cold Brew
Immersion cold brew is known for its rich, full-bodied flavor, resulting from the extended contact between the coffee grounds and water. This method captures nuanced flavors, making it ideal for those who appreciate a more intense coffee experience.
However, the extended brewing time (up to 24 hours) may not be optimal for those seeking a quick coffee fix. For reduced brewing times, vacuum cold brew, or agitation cold brewing will be perfect.
Additionally, immersion cold brew may yield a less clean and more muddied flavor profile compared to the Japanese-style slow drip method.
Why Is Immersion Cold Brew So Popular?
The coffee industry has witnessed a surge in the popularity of immersion cold brew. This phenomenon can be attributed to various benefits:
Cost-Effective and Simple Brewing Method
One of the primary reasons immersion cold brewing has garnered a loyal following is that it requires minimal investment in equipment and supplies. Its simplicity makes it accessible to coffee enthusiasts at every skill level.
Minimal equipment requirement means you can easily and affordably prepare your brew at home or in the office.
From home brewing to specialty coffee shops, immersion cold brew is the easiest and the most cost effective method.
Smoother and Less Acidic Taste Profile
Immersion cold brewing offers a smoother, less acidic flavor than other brewing methods, such as Kyoto-style slow drip. The reduced acidity also allows unique flavors and nuances of different coffee beans to shine, making for a mellower tasting experience.
Long Shelf Life
Like any other cold brew, you can store it in the refrigerator for several days, up to two weeks, without any flavor loss.
We covered immersion cold brewing, explaining its advantages and disadvantages. We compared it against other cold brewing techniques, and hopefully you have now a better understanding of it, beyond the obvious convenience.
While immersion cold brew is the easiest to grasp and it’s a great starting point, we encourage you to explore and experiment with other methods. You can unlock the true potential of your favorite coffee beans and uncover a multitude of flavors.