Tea is one of the world’s most beloved beverages, not least because of its natural caffeine content. But how do caffeine levels differ across tea types? And how do scientists measure caffeine in your cup?

Here’s an approximate caffeine ranking for popular teas per 240ml (8 oz) serving:

• Black Tea: 40-70 mg, robust caffeine punch

• Pu-erh Tea: 30-70 mg, depending on fermentation and aging

• Oolong Tea: 30-50 mg, a balanced moderate caffeine level

• Green Tea: 20-45 mg, lighter but still energizing

• White Tea: 15-30 mg, mild caffeine suitable for sensitive drinkers

• Herbal Teas: Generally 0 mg caffeine, as these are not true teas

The caffeine content is affected by factors such as leaf maturity, oxidation levels, and infusion parameters. For example, longer steeping times and higher water temperatures release more caffeine.

Methods to detect caffeine in tea

1. High Performance Liquid Chromatography (HPLC):
   This method is widely used because it precisely separates caffeine from other compounds and quantifies its concentration. The sample is first extracted, then injected into the HPLC machine, where it passes through a column and is detected by a sensor.

2. Gas Chromatography-Mass Spectrometry (GC-MS):
   GC-MS is useful for identifying caffeine and other chemical components in complex mixtures but requires volatile sample preparation.

3. Spectrophotometry:
   Less specific, this method relies on measuring absorbance of caffeine at certain light wavelengths.

Our team at TeaTeapot often refers to lab-tested caffeine data when curating teas to help customers make informed choices. Explore our range of teas at TeaTeapot’s collection tailored to different caffeine needs.

Whether you want an energizing morning boost or a gentle afternoon lift, understanding caffeine content and testing methods helps you enjoy tea safely and deliciously.