Maruhachi Seichajo's bōcha latte page says that Kenjō Kaga Bōcha may be replaced, in the same quantity, by the company's dark-roast BOTTO! (深炒り焙茶BOTTO!). An instruction to swap only the tea inside a fixed recipe is unusual, and looks like exactly the way to let a difference in roast depth show itself.
The list folds into three
The list folds into three: the tea side (weight of leaf, volume of water, temperature of water, time), the milk side (volume and temperature), and the sweetness. On a day given over to comparing roast levels, everything except the kind of tea stays where it was.
Why the same-quantity swap is not a comparison
The reason the same-quantity swap is not a comparison lies at the receiving end. In the company's own categories, Kenjō Kaga Bōcha sits under “Kaga bōcha (roasted stem tea)” and the dark-roast BOTTO! under “hojicha (roasted leaf tea)”. What has changed is not only the depth of the roast: the part of the plant and the way it is put together differ too. These are two different products.
“Light roast” and “dark roast” are each shop's own words
“Light roast” and “dark roast” printed on a packet are each shop's own words as well. The Japan Tea Central Association's labelling standard settles 17 names, hojicha among them, and roast-level names are not on that list. None of the documents consulted here gives a reference temperature for roast level, either (chapter 6). Buy two packets from two shops and, somewhere along the way, what is being compared stops being clear.
Make it twice under the same conditions, and record both
So the experiments here begin by setting out the conditions. Make it twice under the same conditions, and record both times. One run cannot separate a difference between teas from the variation of the day. On a day when even one condition refuses to hold, it is more useful later to abandon the comparison and call the cup a cup for the record. There are no records yet. What can be written here is the design of the comparison. Results will go to the association's members as records first, as they are completed, and be added to this chapter afterwards.