Hmm… I thought superheating referred to heating water over 100º by pressurizing it, not by heating it at normal pressure without allowing bubbles to form.
Because technically the steam is dissolved in the water above its saturation point, right? If the gas were (say) CO2 instead of steam, wouldn’t “supersaturated” be the correct term?
It would only be able to heat the tea to above 100C if that point of zero nucleation remained undisturbed, and the tea held directly within it; in other words, it’s not possible.
To be clear, the liquid water flashes into steam as soon as it contacts the leaves, so technically it isn’t the supersaturated water itself heating the tea over 100º. But the steam it produces is above 100º, and that’s what heats the tea.
Water is much more likely to get supersaturated in a microwave, because water heats up in the middle of the container where there are no nucleation points. And supersaturated water heats the tea leaves above 100ºC, which can affect the flavor.
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