Cold brew coffee is more popular than ever, with the sector valued at $1.38 billion USD in 2024 and expected to rise to $1.69 billion USD this year. This has been driven by a number of different factors, including the growing quality of cold brew, its prominence as a healthy, sugar-free alternative to energy drinks, and the rise of specialty coffee more widely. Unlike hot brewed coffee, cold brew is more popular in warmer weather, making it more appealing during periods when coffee would traditionally not be. But how long can cold brew coffee last?
Cold brew coffee has a limited shelf life before it becomes dangerous due to its lower acidic activity and the temperature at which it is produced. Therefore, for roasters and coffee shops, it’s important to answer one key question: how long can cold brew coffee last before it becomes a health risk?
To learn more, I attended the Hardtank webinar “How to Prepare Cold Brew Safely: Minimising Microbial Activity” and heard from Krzysztof Barabosz, co-founder of Hard Beans, and Damian Marshall, Product Development Specialist at Urnex. Read on for their insight into the key question of how long can cold brew coffee last and what you can do to address these concerns.
How long can cold brew coffee last?
So, how long can cold brew coffee last? When stored at room temperature in industry-standard kegs, cold brew lasts less than 24 hours before it becomes dangerous.
This was proven in a study undertaken by Hard Beans with the Institute of Biotechnology of the University of Opole, Poland. Keeping various kegs of cold brew at temperatures from 5ºC to 25ºC, all had developed bacteria such as Escherichia coli (E coli) within 24 hours.
In the kegs kept at 25ºC, Krzysztof noted a significant presence of yeast. “This was quite interesting, because coffee doesn’t contain yeast,” he says. “When we assessed the yeast, it came from the palm of [people’s] hands.”
How long can cold brew coffee last as its storage temperature increases, though? In the same study, cold brew stored at 25ºC took less than one day to exceed the European Union’s safety regulations for microbial activity. By the second day of the test, the same was true for kegs stored at 20ºC and 15ºC.
Evidently, cold brew coffee is highly sensitive – more so than traditionally brewed hot coffee. “Cold brew is made without hot water, so there’s nothing to disinfect any kind of microbes in your coffee or equipment,” says Maciej Duszak, co-founder and Head of Sales at Hardbeans.
Cold brew generally has a higher pH than hot coffee, meaning it’s less acidic – and thus, microbes can survive for longer. This means you need to store it at lower temperatures – otherwise, its level of microbial activity becomes unsafe. How long can cold brew coffee last in these conditions, though? Cold brew stored in the correct sealed containers at or below 5ºC can remain safe for up to one week.
How long can cold brew coffee last and what happens if it isn’t stored properly?
Since cold brew coffee is such a sensitive product, storing it properly is essential if you want to serve it safely.
“As a rule, unpasteurised cold brew must be stored below 5ºC,” says Krzysztof. “You need to have a huge, cold storage room where you keep the temperature very low.”
The safety concerns if these conditions aren’t met are particularly important. For example, the mould Penicillium crustosum was found in Hard Beans’ study in cold brew stored above 5ºC. Not only does this spoil the coffee, but it also results in health risks: including tremors, vomiting, and nausea.
Equally, coffee shops, bakeries, or hotels serving cold brew risk breaching local food safety regulations with inadequate storage.
How long can cold brew coffee last in these settings? “After brewing [and storing] at room temperature for one day, the amount of colony-forming units (CFU/ml) was above the European regulation threshold,” Krzysztof says. “That means that, as a coffee shop owner or barista, you need to discard it.”
Since cold brew coffee has a pH of around 4.6, it is classified as “mildly acidic” by both European and American food safety bodies. To adhere to their regulations, cold brew can only spend a maximum of two hours in temperatures above 5ºC.
“In many cases, it’s exposed at the front of a coffee shop,” Krzysztof adds. “It’s quite difficult to keep the equipment clean in these conditions, [and risky] to drink those beverages later on in the day.”
On a logistical level, coffee shops also need dedicated space to store cold brew and its equipment. As a general rule, a coffee shop requires between 10 and 15 square metres of storage space in its backroom.
Of course, it’s unrealistic to expect businesses to reserve all of this space for cold brew storage. However, even low-volume cold brew businesses will require at least one refrigerator running below 5ºC, limiting the remaining space for other coffee and key equipment.
How to extend cold brew shelf life and avoid wastage
While cold brew can only last for up to one week under 5ºC, its volatile nature means that most coffee shops choose to brew it ad hoc – usually preparing cold brew overnight, traditionally with an immersion brewer.
However, traditional cold brew methods require up to 24 hours to reach the desired level of total dissolved solids (TDS). This is both time-consuming and leaves businesses in a precarious position when it comes to demand.
Due to its extended steeping time, if you sell out of cold brew, you can’t have any more ready for that day. Similarly, if you don’t sell all of that day’s batch, you will need to throw the remainder away due to the safety concerns that come with storing it for extended periods. In either case, businesses serving cold brew will lose either money or sales.
To store cold brew for closer to the one-week threshold, Krzysztof advises sterilised bottles kept below 5ºC. “I recommend you use stainless steel or glass,” he says. “If you use plastic, be sure it’s BPA-free or other food-grade plastic.”
Equally, you’ll need to regularly and thoroughly clean your cold brew equipment to remove any microbial contamination. This can’t be taken lightly, and requires extremely specific products are used to clean equipment.
“On a daily basis, you need to use an alkaline cleaner,” says Damian. “Dose it as appropriate on the instructions, but also do a little bit of manual labour. Use a brush to get rid of coffee oils inside buckets or kegs.
“You could make the most fantastic cold brew product, but if you’re not cleaning, over time these oils will build up. Then, you’ve wasted all of your time making a fantastic product.”
Self-cleaning cold brew equipment, such as the Baby Hardtank, provides a solution to both food safety concerns and cold brew yields. It uses recirculation technology to speed up cold brew production by constantly agitating the grounds. This means you can produce a batch of five litres in 45 minutes, preparing cold brew with a much shorter lead time based on customer demand – a sudden spell of warm weather, for instance.
By reducing the time it takes to prepare cold brew, products like the Baby Hardtank give businesses more flexibility, allowing them to minimise wasted coffee and counteract any possible food safety issues. At this point, a question like how long can cold brew coffee last won’t be as big a concern.
Cold brew should be bold, smooth, and safe. With Hardtank’s smart cold brew technology, you can brew with confidence, cut waste, and keep your customers happy: check out the Baby Hardtank here or get in touch with the team to get a custom quote.
FAQ
How long can cold brew coffee last?
At room temperature, cold brew coffee lasts less than 24 hours, which increases to one week when stored under 5ºC.
How long can cold brew coffee last at room temperature if I drink it the same day?
Cold brew coffee at room temperature is only good if it’s within 2 hours of brewing. After that, microbial risks increase dramatically.
How do I know if my cold brew has gone bad?
Signs include a sour smell, off taste, visible mold, or cloudiness. When in doubt, toss it out.
How long can cold brew coffee last in a container?
In a sterilized glass or stainless steel container, or BPA-free plastic, cold brew coffee can last for a short period of time – less than one week.
How long can cold brew coffee last if it is pasteurized?
If you’re mass-producing or bottling, pasteurization helps extend the shelf life of cold brew much further and ensure safety.
How long can cold brew coffee last if it is frozen?
Freezing is a great way to preserve cold brew for a few weeks, but always use airtight containers.
