Cold brew coffee has become very popular in the coffee industry. It serves a beneficial purpose in your daily coffee consumption routine, providing a refreshing and sweet taste. Additionally, it can be equally or even more convenient than using a coffee pod machine.
COLD BREW VS. COLD BREW CONCENTRATE:
Cold brew concentrate refers to cold brew that is prepared using a significantly higher amount of coffee compared to water. Typically, traditional drip coffee has a ratio of 1 part coffee to 16 to 20 parts water, known as its “strength.” On the other hand, cold brew concentrate is commonly made using a ratio ranging from 1:4 to 1:8. It is essentially a concentrated form of coffee beverage, being considerably stronger and containing a higher caffeine content compared to an equal volume of drip coffee liquid.
#1 | HOW IS COLD BREW MADE?
To make cold brew, combine coffee grounds (typically coarse) with cold or room temperature water and let it sit for 8 to 24 hours. The result is the best cold brew.
Cold brew coffee is typically prepared by immersing coffee in water and allowing it to steep for several hours at a cold or room temperature. The gradual and cool brewing process imparts a distinct flavor profile to cold brew, setting it apart from the traditional method of brewing hot coffee using the same type of beans. This unique taste often includes hints of gentle chocolate and subtle, less acidic fruit flavors. To verify this, we conducted our own investigation and documented our results in our blog post entitled “Cold Brew Taste Test: 5 Coffees, Hot vs. Cold”.
Cold brewing, sometimes referred to as brewing at ambient temperature, replaces temperature with time in order to achieve extraction. The duration of cold brewing varies between 8 and 24 hours, depending on different sources and the desired flavor of the cold brew.
In the process of making cold brew coffee, it is common to create a concentrate that is later thinned out or adjusted to taste. While pour-over and most drip coffees have a brewing ratio of approximately 1 part coffee to 16 parts water (for example, 20 grams of ground coffee brewed with 320 mL of water), cold brewing typically involves using less coffee and offers a variety of options to cater to different preferences.
MORE ABOUT COLD BREW RATIOS:When brewing cold brew coffee, a common ratio is 1:8 or 1:9. For example, 50 grams of ground coffee to 450 milliliters of water. Some brewing ratios are even stronger and offer a more concentrated flavor. However, other cold brew recipes have ratios that are closer to hot coffee, such as 1:11 or 1:12. These recipes are specifically for making ready-to-drink cold coffee without the need for dilution. By using a 1:12 ratio, the coffee will have a higher caffeine content by volume. This is where a myth about cold brew may originate, which will be discussed later. |
#2 | COLD BREW VS. ICED COFFEE
In the past, the majority of iced coffee was simply regular brewed drip coffee or espresso with ice added to it. It was not unusual to see a barista or restaurant staff member take coffee from the batch brew, put ice in it, and call it “Iced Coffee,” which may still be the case.
The innovation of “flash chill” or “flash brew” coffee has gained popularity more recently as a method to improve the quality of iced coffee. These methods involve two steps.
- reduce the ratio of water to coffee to account for the added ice that would otherwise dilute the coffee, and
- cool down the hot-brewed coffee immediately by brewing directly into the ice-filled vessel.
Cold brew is prepared by steeping for longer periods of time, in contrast to iced coffee that is brewed with hot water to extract extra layers of flavors and other natural coffee compounds that may not be fully extracted in cold brew.
#3 | WHY DRINK COLD BREW?
- Forgiving brewing process
- Highly convenient
- Less acidic
- All the health and energy benefits of hot coffee
- Great way to use older coffee beans
When you go into more detail, cold brewing is an forgiving method for using coffee beans that are not fresh, and it’s simple to prepare a large amount ahead of time. As a result, it produces a convenient and invigorating beverage for hectic mornings.
Why do folks who drink cold brew often talk about its mild and low acidity? Cold brew coffee is known for being less acidic compared to hot brewed coffee made from the same beans. It’s renowned for its mellow and smooth flavor, not only pleasing to the taste buds but also gentle on the stomach. But what is the reason behind this?
When it comes to science, heat plays a significant role in the extraction process*. Cold brewing, on the other hand, retains certain acids that are effortlessly extracted by hot coffee. As a result, the end result is not only a flavorful, smooth, and mellow coffee, but also one that remains fresh in taste even after several days.
Hot and Cold Brew Coffee Are Chemically Different
There are distinct differences in the taste of coffee when it is cold brewed compared to when it is hot brewed, and these differences go beyond just the temperature. If you have ever tried cooling down a hot coffee and compared it to a cold brew, you may have noticed this contrast in flavor. This raises the question of whether there are chemical disparities between hot brewed and cold brewed coffee. The researchers at Thomas Jefferson University believe that not much scientific exploration has been conducted on this topic, partly because cold brew has gained popularity more recently. Nonetheless, they have been working towards unraveling this mystery and, specifically, they recently focused on investigating the impact of various roasts on the outcomes.
The researchers conducted a study comparing acidity levels, antioxidants, and caffeine levels in cold and hot brewed coffee. They examined a variety of roasts, ranging from light to dark. Surprisingly, while caffeine is commonly associated with coffee consumption, this study discovered minimal variations in caffeine levels across roast or temperature, except for slightly higher levels in hot coffee compared to cold brew and in light roasts compared to dark roasts. On the other hand, the most significant disparities were found in antioxidants and acidity.
According to Niny Z. Rao, the principal investigator of the project and in the announcement of the results made through the American Chemical Society, hot brewing extracts more antioxidants from the grind compared to cold brew, and this disparity becomes more pronounced with an increase in the degree of roasting. To put it differently, regardless of the roast, hot brewed coffee appeared to maintain a consistent level of antioxidant activity, whereas cold brew coffee exhibited slightly lower antioxidant activity for light roasts, which further decreased as the roast became darker. Consequently, in theory, Rao suggests that a hot brewed dark roast coffee might be healthier than a cold brewed dark roast coffee.
According to the findings, cold brew coffees, regardless of the roast temperature, possessed slightly lower acidity when compared to hot brew coffees. The total titratable acidity (TA) of all coffees decreased as the roasting temperature increased. Moreover, as the roasting temperature increased, there was a slight rise in the differences of TA between cold and hot brew coffees, suggesting that the extraction processes are influenced by the roasting procedure.
For consumers, who are not experts in chemistry, what does all of this information imply? Summarizing, Rao suggested, “I have always advised consumers to drink the coffee they enjoy. However, if you want to create a coffee beverage with antioxidants or consider acidity, you should consider the roast level. Opt for a darker roast if you prefer a low-acid drink. It is important to note, though, that the difference in antioxidant content between hot- and cold-brew coffee is much greater for a darker roast.”
In order to ensure fair comparison, the researchers used medium grinds for both hot and cold brewing in their study, despite the fact that cold brew is typically made with coarse grinds. It would be intriguing to observe how these drinks compare when prepared using less scientific and more traditional methods.
Nevertheless, the abstract of the study draws a clear conclusion by stating that the chemistry of the final coffee brew is greatly affected by the temperature at which the beans are roasted. Crafting cold brew coffee beverages should therefore take this factor into consideration. Additionally, it is worth noting that the taste of the coffee is also influenced by the roasting process, something that should not be disregarded despite its subjective nature. However, this remark is not intended to undermine the significance of scientific findings.