Making the perfect pot of tea isn’t easy. In fact, the task requires such focus and skill that Douglas Adams decided it should be one deserving of a space-computer’s attention. In further fact, the International Standardization Organization even awards an ISO 3103 standard to he who can brew the perfect cup – one it has defined to painful precision as a series of 10 steps (for a larger variant of pot).
The first step is a requirement: that the pot should be glazed earthenware. When a receptacle fashioned out of clay is fired to about 1,000-1,150 degrees Celsius, in a process generally referred to as bisque-firing, it retains its porosity and makes it unsuitable to hold fluids. The watertight quality is imparted to it by applying a patina of powdered glass to the pot’s surface and firing it to between 950-1,050 degrees Celsius, a technique called glazing.
When producing pottery that is eventually going to be used to hold liquids, potters ensure that the bisque-firing temperature is higher than the glaze-temperature. If the glazing temperature is increased, then gases trapped in the pores of the pot begin to expand even as the powdered glass begins to fuse and become a liquid. Just before it solidifies into a hard shell, however, the expanding gases cause it to bloat. This distorts the overall appearance as well as ruins the functional purpose of the glaze.
There’s another problem before we get to make the tea itself. The substrate – or the material on which glazing is performed, in this case the pot – shouldn’t melt during glazing for any reasons (or, like in most cases, the presence of impurities like large grains). This means it’s advantageous if the glass powder melts and becomes a shell as fast as it can, and to make this happen, a ceramic flux is mixed with it. Lead silicate is the most commonly used flux material. During the heating in the kiln, it promotes the quick formation of a small amount of glass that holds neighbouring crystalline formations in the molecular lattice together.
Just one last thing. Apart from holding the water, water will also have to be boiled in the pot. As the water heats up, gas trapped in the water also heats up, and must be released. Yes, the lid is on loose, but the imprisoned hot air must annex into bubbles first, rise up, and escape as part of the steam. If the insides of the pot are smooth, then bubble-formation is not encouraged because no appreciable turbulence is introduced into the system. Without turbulence, there is no entropy – or chaos – infused to promote bubbling. As a result, the boiled water exists in the superheated state, and when it is poured, there’s a good chance it will fall back to the heated state by violently burping out the heat and splashing out. So, keep the insides rough.
OK, we can make tea now… if all this time we’ve ensured that the pot weighs anything between 190 and 210 grams and can hold anywhere between 302 and 318 millilitres of water. You have? Good for you. Now, carefully measure out between 1.96 and 2.04 grams of tea, and add as many such quanta per 100 millilitres of water you’re going to pour into the pot. Next, carefully pour freshly boiling water in but only up to 4-6 millimetres of the brim. Anymore and you risk losing the prestigious 3103 standard. And if you haven’t noticed yet, the tricky part is to figure out how much water the pot currently holds (so you can go back in time and get the grams-of-tea bit right).
Let the water cool for 20 seconds before the 6-minute long brewing process commences. During brewing, a naturally-occurring class of compounds with a large and complex chemical composition is extracted from the tea: the phenols. A phenol is any molecule that possesses a hydroxyl ion (OH-), and lends its name to alcohol for the same reason. A type of phenol called flavonoids, and a sub-type of flavonoids called catechins, is found in sizeable amounts in crushed tea leaves and is retained through the entire processing period. These flavonoids are anti-oxidants (oxygen-liberating), and present suggestive anti-allergic, anti-microbial and anti-inflammatory behaviours, too.
Once these flavonoids are dissolved in the water, the brewing is said to be done and the tea is ready for the drinking. If you like milk in your tea, however, there are a couple more steps. First, transfer the tea to a larger glazed earthenware bowl (because the ISO thinks you might not figure out that pouring the milk makes the tea overflow in the smaller bowl). This second bowl must weigh between 180 and 220 grams and have a volume of 380 millilitres. Once the tea has been transferred, add 5 millilitres of milk at a temperature of 65-80 degrees Celsius. If milk any colder or warmer is added, an important thermal equilibrium becomes distorted.
The equilibrium is significant for two reasons. The first reason has to do with the fact that when consuming a hot liquid, the chance of making a “vulgar” slurping sound increases while sipping if the liquid is hotter (again, to do with bubble formation). This means that the resulting solution of milk and tea must be sufficiently cool as to not present any opportunities for an uptight gentleman to make farting noises from his lips. At the same time, the solution should also be warm enough for the two liquids to mix uniformly. This precariously fine balance of temperatures is established by keeping the milk between 65 and 80 degrees Celsius.
Now, you may drink the tea while basking in the glory of your having beaten a computer designed to fly spaceships at the ends of universes along with the assistance the computer derived from an infinitely smart but neurotically depressed robot.
Tea is an elixir whose experience begins in fires and ends in the soul. Even brushing its valuable health benefits aside: the precision that brewing a great pot of tea demands can only be a measure of its improbable finesse and fragilely supported assortment of flavour, warmth, sensation, energy, and satisfaction. And where precision is concerned, you can always count on the nerd.
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