Cold brew is steeped in cold water for 12 to 24 hours and is smoother and less acidic, while iced coffee is hot-brewed coffee that is chilled.
Cold brew
- Coarse grounds steeped in cold water 12 to 24 hours.
- Smoother, less acidic and sweeter.
- Often brewed as a concentrate.
Iced coffee
- Hot brewed, then cooled or poured over ice.
- Brighter and more acidic, can dilute as the ice melts.
Caffeine
Cold brew concentrate can have more caffeine per ounce, but diluted servings are close to regular coffee.
Cost
Cold brew is usually pricier because of the time and coffee used.
Brewing method
Cold brew is made by steeping coarse ground coffee in cold or room temperature water for 12 to 24 hours, then filtering. Iced coffee is hot brewed coffee, often made stronger, and then cooled over ice.
Taste
Cold brew has lower perceived acidity and bitterness, a smoother and slightly sweet taste. Hot extraction brings out more acids and aromatic compounds, which gives iced coffee a brighter, more complex flavor.
Acidity
A study in the journal Scientific Reports (2018) found cold brew and hot brew had similar pH values of about 4.85 to 5.13, but hot brews had more acidic compounds that affect flavor.
Caffeine
Caffeine depends on the coffee to water ratio and the time. A typical 16 ounce cold brew concentrate diluted can contain about 150 to 250 milligrams, and some coffee shop cold brews have more than iced coffee. A 16 ounce iced coffee typically contains about 165 milligrams.
Concentrate
Cold brew is often made as a concentrate with a 1:4 to 1:8 coffee to water ratio, then diluted with water or milk.
Storage
Cold brew can be kept refrigerated for 7 to 14 days, while hot coffee left to cool loses flavor within a day.
Cost
Cold brew uses more coffee grounds per serving and takes longer, so it costs more in cafes, often 1 to 2 dollars more than iced coffee.
Making at home
- Use 1 cup coarse ground coffee for 4 cups water.
- Steep 12 to 18 hours in the fridge.
- Strain through a fine mesh or paper filter.
Japanese iced coffee
This method brews hot coffee directly onto ice to lock in aromas.
Health note
The FDA says up to 400 milligrams of caffeine a day is safe for most healthy adults.
Brewing method and chemistry
Cold brew is made by steeping coarse ground coffee in cool or room temperature water for 12 to 24 hours, then filtering, which gives a smooth, low bitterness concentrate. Iced coffee is regular coffee brewed hot, usually at about 195 to 205 F, then cooled and poured over ice, which can dilute and taste more acidic or bitter. Japanese style iced coffee brews hot coffee directly over ice to lock in aroma. A 2018 study in Scientific Reports found the pH of cold and hot brews was similar, but cold brew had lower titratable acidity in some cases, which may explain its smoother taste.
Caffeine, storage and cost
Caffeine depends on the ratio of coffee to water and the dilution. Cold brew concentrate is often 1 part coffee to 4 to 8 parts water, and diluted servings may contain 100 to 200 mg per 12 ounces, which is comparable to or higher than hot coffee at about 95 mg per 8 ounces. Cold brew keeps in the fridge for about 7 to 10 days, while iced coffee is best the same day. Cold brew at coffee shops often costs more because of the longer brewing time and more coffee used. To make it at home, use a jar, coarse grounds and a filter.
Based on data from the journal Scientific Reports and the USDA FoodData Central
