To make cold brew coffee, steep coarse-ground coffee in cold or room-temperature water for 12-24 hours (16 hours is the sweet spot), then strain out the grounds and refrigerate. The result is a smooth, naturally sweet, low-acid coffee concentrate that you can drink over ice, dilute with water or milk, or use as a base for iced coffee drinks. It is one of the simplest coffee brewing methods that exists , all you need is ground coffee, water, a container and patience.
Cold brew is not iced coffee. Iced coffee is hot-brewed coffee poured over ice , it has the acidity and bitterness of a hot brew, just chilled. Cold brew is never heated , the cold water extracts different compounds from the coffee, producing a fundamentally different flavour profile: smoother, sweeter, less acidic and more mellow. If you have found iced coffee harsh or bitter, cold brew is the answer.
We do not sell cold brew as a product, but we do roast some exceptional coffees that are purpose-built for cold brewing at home. This guide covers everything you need to make café-quality cold brew in your own kitchen , including which beans to use, ratios for concentrate and ready-to-drink, and tips for getting the best results.
What Is Cold Brew Coffee?
Cold brew is coffee brewed with cold or room-temperature water over an extended period , typically 12 to 24 hours. The long steep time compensates for the low temperature: hot water extracts flavour compounds from coffee in minutes, but cold water takes hours to achieve equivalent extraction.
The key difference is which compounds are extracted. Hot water readily dissolves the acids and bitter compounds that give hot coffee its sharp, bright character. Cold water extracts these compounds much more slowly, meaning a cold-steeped coffee has significantly less perceived acidity and bitterness. The sugars, chocolates and smooth, rounded flavour compounds are extracted effectively in cold water , giving cold brew its characteristic mellow sweetness.
Cold Brew vs Iced Coffee
| Cold Brew | Iced Coffee | |
|---|---|---|
| Water temperature | Cold / room temperature | Hot, then cooled |
| Brew time | 12-24 hours | 2-5 minutes |
| Acidity | Low , smooth and mellow | Normal , same as hot coffee |
| Bitterness | Very low | Normal to high (ice dilution can help) |
| Caffeine | Higher (concentrate: 150-200mg/250ml) | Standard (80-100mg/250ml) |
| Flavour | Smooth, sweet, chocolate, caramel | Bright, acidic, can taste diluted |
| Shelf life | Up to 2 weeks refrigerated | Best consumed immediately |
Equipment Needed
Cold brew requires almost no specialised equipment:
- A large container , a mason jar, a French press, a large jug or a purpose-built cold brew maker. Anything that can hold coffee and water and be covered.
- Coarse-ground coffee , the same grind you would use for a cafetiere (sea salt texture). Whole bean is ideal , grind just before steeping.
- Cold or room-temperature water , filtered water produces a cleaner taste.
- A strainer , a fine-mesh sieve, cheesecloth, a nut milk bag, or a French press plunger. You need to separate the grounds from the liquid after steeping.
- A storage container , a bottle or jar for the finished cold brew. Glass is preferable to plastic for storage.
Cold Brew Recipe: Step by Step
Concentrate Recipe (1:8 Ratio)
This produces a strong concentrate that you dilute before drinking , the standard method for most cold brew makers. The concentrate is versatile: dilute with water, milk, oat milk or tonic water for different drinks.
Step 1: Grind Your Coffee
Grind 100g of coffee to a coarse grind , the texture of coarse sea salt, similar to a cafetiere grind. If using pre-ground coffee, cafetiere grind is the correct size. Avoid anything finer than medium , fine grounds over-extract during the long steep and produce a bitter, gritty concentrate.
Step 2: Combine Coffee and Water
Place the ground coffee in your container and pour 800ml of cold or room-temperature water over it (100g coffee : 800ml water = 1:8 ratio). Stir gently to ensure all grounds are fully saturated , dry clumps on the surface will not extract properly.
Step 3: Cover and Steep
Cover the container and leave it at room temperature or in the fridge for 16 hours. Room temperature extraction is slightly faster and produces a slightly fuller body. Fridge extraction is slower and produces a cleaner, more delicate result. Both are excellent , experiment to find your preference.
- 12 hours: lighter body, slightly under-extracted, clean
- 16 hours: the sweet spot , full body, smooth sweetness, balanced
- 20 hours: maximum body, starting to develop slight bitterness
- 24 hours: very full extraction , can be over-extracted depending on grind and beans
Step 4: Strain
After steeping, strain the coffee to remove all grounds. For the cleanest result, strain twice , once through a coarse sieve to remove the bulk of the grounds, then through a fine-mesh sieve, cheesecloth or paper coffee filter to remove fines and sediment. If using a French press, simply press the plunger down and pour.
Step 5: Store
Transfer the concentrate to a clean glass bottle or jar. Store in the fridge. Cold brew concentrate keeps for up to 2 weeks refrigerated , one of the biggest practical advantages over hot-brewed coffee, which should be consumed within hours.
Step 6: Dilute and Serve
The 1:8 concentrate is too strong to drink neat (for most people). Dilute 1:1 with cold water for a standard iced coffee strength, or 1:2 for a lighter drink. Add ice, milk, oat milk, tonic water or flavoured syrups to taste. The concentrate is also excellent in cocktails , espresso martinis and coffee Old Fashioneds made with cold brew concentrate are outstanding.
Ready-to-Drink Recipe (1:15 Ratio)
If you prefer not to dilute, use a 1:15 ratio instead: 50g of coarse-ground coffee to 750ml of cold water. Steep for 16-20 hours, strain, and drink as-is over ice. No dilution needed. This produces a drink that is ready to go straight from the fridge.
The Hot Bloom Method
This is an advanced technique that combines a brief hot-water bloom with cold steeping for a more complex cold brew. The hot bloom extracts aromatic compounds that cold water alone cannot access, while the cold steep provides the smooth, low-acid body.
- Use your standard cold brew recipe (100g coffee, 1:8 ratio).
- Instead of cold water, start by pouring 200ml of hot water (93°C) over the grounds. Wait 45 seconds , this blooms the coffee and releases trapped CO2 and volatile aromatics.
- After 45 seconds, add the remaining 600ml of cold or room-temperature water.
- Stir, cover, and steep for 12-14 hours (the hot bloom accelerates early extraction, so you need slightly less total time).
- Strain and store as normal.
The result is a cold brew with noticeably more aroma and complexity than the all-cold method , the chocolate, fruit and floral notes that would otherwise be lost to cold extraction are partially captured by the bloom. Worth trying if you find standard cold brew too one-dimensional.
Best Coffee Beans for Cold Brew
Cold brew's smooth, low-acid character pairs best with coffees that have rich body, chocolate and caramel notes, and a bold, full flavour that can stand up to ice and dilution. Medium and dark roasts are the classic choice , their roast-developed sweetness and body translate beautifully into cold brew. Light roasts can work but will produce a more tea-like, delicate result that some drinkers find underwhelming when served cold.
Our top picks for cold brew:
- Indonesian Burni Telong , a bold dark roast with earthy depth, dark spice and a heavy body. The quintessential cold brew bean , its low acidity and rich character are amplified by cold extraction. The result is intensely smooth and deeply flavourful.
- Dolce Vita , our Italian-style dark roast blend with dark chocolate, toasted almond and a full, syrupy body. Cold brew concentrate made with Dolce Vita is excellent neat over ice or with a splash of oat milk.
- Blazing Trails , our boldest, darkest blend. Smoky, intense, with a deep, lingering finish. Makes a powerful cold brew concentrate that holds its character even when diluted 1:2 or mixed into cocktails.
- Brazilian Santa Hedwirges , a natural-processed medium roast with dark chocolate, hazelnut and caramel. Produces a wonderfully sweet, nutty cold brew with a velvety texture. An excellent all-round choice.
For cold brew, we recommend buying whole bean and grinding fresh just before steeping. A coarse grind , the same setting you would use for a cafetiere , is correct. Browse our dark roast range and medium roast range for more cold brew-friendly options.
Storage and Shelf Life
Cold brew concentrate keeps for up to 2 weeks in the fridge in a sealed container. This is one of its biggest practical advantages , you can make a large batch on Sunday and drink it all week.
Ready-to-drink (1:15 ratio) cold brew is best consumed within 7-10 days. Once diluted, it degrades faster than concentrate.
Signs your cold brew has gone off: sour or funky smell, visible mould, or a sharp, vinegary taste. When in doubt, discard and brew fresh , at the cost of a few pounds of coffee and 16 hours of waiting, it is not worth drinking questionable cold brew.
Store in glass rather than plastic , glass is non-reactive and does not absorb flavours. Keep the container sealed to prevent the cold brew absorbing fridge odours.
Common Cold Brew Mistakes
1. Grinding Too Fine
Fine grounds over-extract during the long steep, producing a bitter, harsh, over-saturated cold brew. They also make straining difficult , you will end up with a gritty, silty drink. Use a coarse grind, always.
2. Steeping Too Long
Beyond 20-24 hours, over-extraction becomes increasingly likely. The cold brew will start to develop bitterness and astringency that defeats the purpose of the method. 16 hours is the sweet spot for most beans.
3. Using Stale Coffee
Cold brew amplifies whatever is in the bean , good or bad. Stale, flat coffee produces stale, flat cold brew. Use freshly roasted coffee (within 4 weeks of roast date) for the best results.
4. Not Straining Thoroughly
A single pass through a coarse sieve leaves fine sediment that makes the cold brew silty and gritty. Double-strain , coarse sieve first, then fine mesh or paper filter , for a clean, smooth result.
5. Drinking Concentrate Neat
The 1:8 concentrate is extremely strong. It is designed to be diluted. Drinking it neat can cause stomach discomfort and an excessive caffeine hit (200mg+ per glass). Dilute at least 1:1 with water or milk.
Frequently Asked Questions
How long does cold brew take to make?
Cold brew takes 12-24 hours of steeping time, with 16 hours being the recommended sweet spot. The active preparation time is only 5-10 minutes , grinding the coffee, combining it with water, and straining after steeping. It is an overnight process: prepare it in the evening, strain in the morning, and drink it all week.
What is the best ratio for cold brew coffee?
For concentrate (dilute before drinking): use a 1:8 ratio . 100g of coarse-ground coffee to 800ml of cold water. Dilute 1:1 with water, milk or oat milk before serving. For ready-to-drink (no dilution needed): use a 1:15 ratio . 50g of coffee to 750ml of water. The concentrate method is more versatile and produces a longer-lasting batch.
Is cold brew the same as iced coffee?
No. Cold brew is brewed with cold water over 12-24 hours and is never heated. Iced coffee is hot-brewed coffee that is cooled and served over ice. They taste fundamentally different , cold brew is smooth, sweet and low-acid, while iced coffee retains the acidity and bitterness of hot coffee. Cold brew also keeps for up to 2 weeks refrigerated, while iced coffee should be consumed immediately.
How long does cold brew last in the fridge?
Cold brew concentrate keeps for up to 2 weeks in a sealed glass container in the fridge. Ready-to-drink (diluted) cold brew is best consumed within 7-10 days. Store in glass rather than plastic, keep the container sealed, and discard if you notice a sour smell, off taste or visible mould.
Does cold brew have more caffeine than regular coffee?
Cold brew concentrate typically has more caffeine than a standard cup of hot coffee , approximately 150-200mg per 250ml versus 80-100mg. This is because of the high coffee-to-water ratio (1:8 for concentrate versus 1:15 for filter). When diluted 1:1 to drinking strength, cold brew caffeine content is roughly comparable to filter coffee. If you are caffeine-sensitive, dilute your cold brew more generously.
What is the best grind for cold brew?
Use a coarse grind , the same texture as cafetiere grind, roughly like coarse sea salt. Coarse grounds extract slowly over the long steep without over-extracting, producing a smooth, sweet cold brew. Fine grounds will over-extract during 12-24 hours of steeping, resulting in a bitter, harsh, gritty concentrate. If buying pre-ground, choose "cafetiere grind" or "coarse grind."
Can I make cold brew with any coffee?
Yes , any coffee can be cold brewed. However, medium and dark roasts produce the best results because their chocolatey, caramelly, full-bodied character is amplified by cold extraction. Light roasts produce a more delicate, tea-like cold brew that some people enjoy but others find underwhelming. For the richest, smoothest cold brew, we recommend our Indonesian Burni Telong, Dolce Vita or Blazing Trails blends.
Best Beans for Cold Brew
Cold brew rewards bold, rich coffees with body and sweetness. Our top recommendations are the Indonesian Burni Telong (earthy, bold, smooth), Dolce Vita (dark chocolate, almond), Blazing Trails (our boldest blend) and Brazilian Santa Hedwirges (chocolate, hazelnut, caramel).
Buy whole bean and grind fresh for the best results. Browse our dark roast and medium roast ranges for more cold brew-friendly options. All coffees are flame-roasted in small batches in Glasgow, SCA-scored to speciality grade, and dispatched within days of roasting. Free delivery on orders over £25.
