ISO 3103: The Standardized Method For Brewing Tea

ISO 3103 is the standardized method for brewing tea.

Do you think you know how to brew a cup of tea? Here's how you should brew one, according to the International Organization for Standardization (ISO).

To maintain consistent results, the following are recommendations given by the standard:

• The pot should be white porcelain or glazed earthenware and have a partly serrated edge. It should have a lid that fits loosely inside the pot.
• If a large pot is used, it should hold a maximum of 310 ml (±8 ml) and must weigh 200 g (±10 g).
• If a small pot is used, it should hold a maximum of 150 ml (±4 ml) and must weigh 118 g (±10 g).
• 2 grams of tea (measured to ±2% accuracy) per 100 ml boiling water is placed into the pot.
• Freshly boiling water is poured into the pot to within 4-6 mm of the brim.
• The water should be similar to the drinking water where the tea will be consumed
• Brewing time is six minutes.
• The brewed tea is then poured into a white porcelain or glazed earthenware bowl.
• If a large bowl is used, it must have a capacity of 380 ml and weigh 200 g (±20 g)
• If a small bowl is used, it must have a capacity of 200 ml and weigh 105 g (±20 g)
• If the test involves milk, then it can be added before or after pouring the infused tea.
• Milk added after the pouring of tea is best tasted when the liquid is between 65 - 80 °C.
• 5 ml of milk for the large bowl, or 2.5 ml for the small bowl, is used.