Did you know that there are a host of benefits to brewing coffee using cold water versus hot? Is the PH for cold brew higher or lower? We'll cover this and much more in this article, and you may be surprised to learn that there are some prevalent myths to debunk.
Whether you're sweating in the blistering heat of summertime or shivering in the frigid chills of winter, hot and cold temperature aside, many people believe that coffee is always best when served cold year-round. The interesting thing is that most people still boil water, then pour it over coffee beans or at the very least use a drip machine first before adding ice. Wouldn't it be better to brew it all from a cooler state, to begin with? That's a pretty cool idea! In fact, more and more coffee aficionados swear by the cold-brewed coffee brewing method for their daily cup.
Heat Makes Coffee More Acidic
Of course, heat will accelerate the brewing process, but it does more than that. Heat makes coffee more acidic, right?
Conventional wisdom suggests that heat is the reason for acid extractions in your coffee. While oils, acids, and other molecules separate more easily from coffee beans between 195 to 205 degrees Fahrenheit, the acids appear to separate from the mash no matter the temperature.
But if your beans never reach that temperature range while brewing, those compounds won't extract, right? They may take longer to extract fully, but given long enough most of the compounds will absorb into your coffee. So then why is cold brew less acidic?
If you use alkaline or super-alkaline water to extract the coffee, the result will be less acidic, but otherwise expect similar acidity levels between cold and hot brew.
Our upset stomachs completely disagree though. Why would your stomach hurt more from hot brew over a cold brew? We believe, though tests need to be performed, that there are other compounds within coffee that react poorly in our stomachs, but that those compounds are missing from cold brew extractions.
The short answer is that we don't exactly know why, but we at the Cold Brew Hub prefer brewing without a kettle because we feel the results that cold brews offer are better than traditional methods. We also avoid the coffee shop whenever we can because brewing coffee is not that difficult.
What is Cold Brew?
Cold brewing is sometimes called Toddy brewing because Todd Simpson claimed that he tasted his first cold-brew coffee in 1964 when in Peru and brought back the process to the USA. While it’s hard to say who the first to come up with the concept, the truth is, if something is put in water and the item is water-soluble, it will infuse its flavor into the water.
Water-soluble means that it mixes with water efficiently. You can age whiskey in sherry wood, and it will take on the flavor. You can add berries to your vodka, and it will take on the flavor. Coffee works similarly.
If you put coffee grounds in water for 12 or more hours, you’ve got coffee. In a sense, all it means to cold brew is to put something in the water and let it steep for a while.
WHAT ARE THE CHARACTERISTICS OF COLD BREW COFFEE?
Cold brew coffee has some interesting characteristics that set it apart from regular coffee. We'll break it down based on the three most important factors you care about.
- Caffeine Content
- Flavor Profile
One of the most prevalent ideas is that cold brew coffee is more caffeinated. According to Starbucks' nutritional facts suggests that their standard cold brew coffee averages at about 12.5-13mg of caffeine per oz of coffee depending on the roast.
Does Cold Brew Coffee Have Less Caffeine?
According to this chart, the biggest caffeine driver is in the way it is roasted. Medium roasts tend to have more caffeine content than dark roasts for cold brew.
"In both samples, the cold brew coffee was found to have the higher concentration of caffeine."
For the most part, the entire coffee product menu at Starbucks has relatively the same range of caffeine content with a couple of exceptions. Nitro Cold Brew has a lot of caffeine and it should be no surprise that espresso leads the pack in caffeine content.
So depending on how you plan to enjoy your morning brew, consider that unless you are including Nitro or espresso, you are getting around the same caffeine content. Some proponents of cold brew coffee suggest that cold brew has higher caffeine content. Why is this?
Well, the concentration of coffee plays the largest part. Generally, you'll use more coffee to water ratio in a cold brew over a hot brew. Because you are using more beans, the strength will increase in a cold brew. So why does this not show in the Starbucks lineup?
Starbucks adds in ice and other additives to their beverages which will essentially water down the result. This would explain why the Nitro cold brew is so densely packed with caffeine over their iced variations.
Starbucks likes to fill a cup with ice first and then add in the cold brew and sweeteners after, but they don't do this for their Nitros. This may make you wonder what sorts of beans Starbucks uses for their coffee since the caffeine levels remain consistent otherwise.
So does cold brew coffee have less caffeine than regular coffee? Yes, you'll reduce caffeine when you add in ice, but not really if you drink it straight up as a concentrate.
If you have ever tried a coffee brewed with cold water, one of the first things you would notice is how much flavor it has. You may notice fruity, nutty, chocolatey, or even floral notes with a cold-brewed coffee that you would miss out on with a hot brew.
Cold brewing itself is not lower in acid, but other flavors within the coffee are detectable. You'll catch the subtle undertones of fruit, nuts, and chocolate.
While you can use any beans you desire, many coffee shops prefer single-origin coffee beans for cold brewing, especially those that come from South America and Latin America. While you may want to find a coffee bean and use nothing else, you should experiment with other varieties and origins to get an idea of what you’ve been missing.
You'll experience a more balanced flavor, with the added sweetness that you cannot match any other way. You may discover your new favorite drink! Once you know what you like, you can say "goodbye" to the coffee shop and "hello" to brewing delicious cold brew at home.
While the brewing process can change the way the coffee tastes, you’re likely used to the burnt flavor that comes with it. When you remove that, you'll taste the coffee's actual flavor.
Let's discuss one of the reasons why.
The Tannic Tango
Hot brew coffee usually tastes more bitter when compared to cold-brewed varieties due to a compounds known as tannins. What are tannins?
Similar to tea, when you add hot water to coffee beans, the heat extracts the caffeine molecules, antioxidants, oils, and other compounds known as tannins. Tannins are natural substances most prevalent in the skins of fruits which when brewed become present in beer, wine, fruit juices, nuts, smoked food, herbs and spices.
Have you ever tasted a red wine and your mouth just wants to pucker up? The cause of this phenomenon is due to tannins. How does this work?
Well, tannins are naturally bitter and your tongue and the proteins attached to it react. When you mix tannins with the proteins on your tongue, the reaction causes a sort of tannic dance in your mouth. It makes certain beverages like wine and coffee an "acquired taste."
While drinking coffee, you might equate the taste sensation to a light grittiness, and no I am not referring to what happens when you accidentally drink a stray coffee ground. Tannins add a flavor texture in hot brew versus a smooth texture in cold-brewed beverages that do not contain as many tannins.
How water causes tannic compounds to bind with water molecules, so they are ever-present in hot coffee. While they may also appear in cold-brewed drinks, less of these tannins appear because it may take longer for those tannins to extract. That is to say, if you steep your coffee grounds in cold water for longer than 24 hours, you may notice an increased bitterness and acidity to your brew.
Tannins are acidic after all. Speaking of cold brew acidity, let's cover that right quick.
If you suffer from acid reflux but love coffee, you may have heard that cold brew coffee is less acidic than hot coffee. Some brewers claim that cold-brew coffee is bland, but they are likely using the wrong coffee beans, or they let the brewed coffee sit out too long and oxidize.
We already covered that there are sweeter flavors when you steep coffee grounds in cold water, now let's talk about the acidic contents in cold brew coffee.
Cold Brew Coffee Acidity
According to a Toddy self-funded study, cold brew coffee is 67% less acidic than regular hot coffee. What's more, some coffee lovers prefer the less-bitter taste of most cold brews because it is a change of pace from the traditional regular hot-brewed varieties.
These findings may not actually be true, however. According to this study and other supporting studies, the chlorogenic acid contents, which affecting resulting PH levels were comparable in all tests and variations of hot versus cold brew methods.
Coffee drinkers love that cold water steeping locks in the flavor without hurting their stomach. Did you know you can drink cold brew coffee for up to 2 weeks after brewing it, if you store it in the fridge? Talk about benefits! These benefits, however seem to have nothing to do with acidity.
If you've ever had gas-station coffee in the morning and wondered why it tastes so bad, it's likely because the pot has sat there on the warmer for a while. This isn't the case with cold brew, however. Day-old cold-brew coffee doesn't taste stale like traditional day-old hot-brewed coffee.
Now you are saving a lot time in the morning too!
What is the PH of Cold Brew Coffee?
According to the study we referenced before, the PH is comparable between cold and hot brews coming in at about 5.5. The human body has a natural PH of 7.5+ depending on the alkalinity of foods and beverages the individual consumes. If you use a more alkaline water source for your ice, your coffee may have a higher PH.
Are you still convinced that cold brewed coffee is less acidic?
The bitter flavor comes from what we covered before with tannins. Since tannins are less present in cold brew coffee, the resulting cup of coffee will have less bitterness. I hope we've dispelled a myth here.
How to Make Coffee Less Acidic
Freeze some high-alkaline water into ice cubes and add them to your coffee or use high PH alkaline water to make your coffee less acidic.
Do you remember the first time you tasted coffee as a kid or teenager? You always imagined the robustness of flavor based on the strong smell, but it never lived up to the smells, did it?
Cold brewing can close the smell-to-taste gap and taste is in the chemistry. We covered before if you expose your coffee grounds to heat, the grounds release oils that don’t dissolve at the low temperature. Those oils packed full of bitter compounds that give your beverage its famously acidic taste.
Therefore, it is safe to say that cold brew bitterness is lower because the water used to extract isn’t hot. You use cool or room-temperature water, which prevents those oils from being released from the beans as quickly.
Plus, the heat shock of hot-brewed coffee prevents you from tasting all the subtle differences within the coffee flavor. The bitterness might not matter much for hot coffee, but if you pour it over ice, you don’t get all the flavors associated with cold-brew. That is one major difference of cold brew coffee vs. iced coffee.
That’s the primary reason people add sugar and milk; the true flavor (which is naturally sweet) is removed, and you need to re-flavor the coffee. That also adds a lot of calories to an otherwise low-calorie beverage.
Cold-brew coffee might be a healthier alternative to regular hot-brew coffee as long as you don't add in sweeteners. The acidity is the same, so it may not help your heartburn and acid reflux, but the burnt flavor is gone.
Coffee's change in taste primarily comes from a change in temperature while brewing it, but since you don’t have any brewing after you heat up a cup of cold brew, the original flavor is locked. Once you finish the brewing process and put it in the refrigerator, the taste remains the same, allowing you to drink day-old cold-brew coffee without it tasting stale.
Easy Cold Brew French Press Recipe
There are many benefits to brewing your coffee the cold way, but it does take longer to brew. If you plan to have some cold brew tomorrow, you may want to wake up earlier today and make it.
A simple French press and a coarse grinder are all you really need. Still, there are better alternatives to a French press for cold brew, like these. Of course, you don’t need a lot of specialty equipment, but you can save a lot of time in the brewing process if you use the right tools for the job.
- If you are going to use a French press, however, make sure you use fresh beans and grind only the amount you require.
- It is better to use a coarse grind from a hand-crank or slow conical burr grinder for the best results.
- Put the coffee in your French press, and pour water slowly over the beans evenly.
- Let it sit for 12-16 hours at room temperature or in the fridge for no more than 24 hours.
- Pour the desired amount into your coffee mug and drink it up!
Tips for a Better Cup
- Make sure you strain and filter the finer sediment from the press.
- Dilute with water or ice cubes the coffee is too strong.
- Freeze the leftover cold brew into ice cubes for another day.
- Choose an airtight cold brew coffee maker to prevent food smells from steeping into the batch.
So is cold-brewed coffee less acidic than hot? Even though tons of marketers claim that it is, science suggests that cold brewed coffee's acidity levels are comparable to hot coffee. If you are a person with a sensitive stomach, heartburn or acid reflux, then you may have fewer issues with cold-brew versus regular coffee, but it won't be because of the acid content.
We know this topic is controversial, because most of the internet makes wild health claims, and the study that Toddy self-published could also just be fanciful marketing that has duped us all. If you have any scientific resources that support Toddy's claims, please discuss below!