With regards to the idea of measuring resistance through water.
I started wondering if resistance could be applied as a measure of the brewiness of an infusion.
And in style with the "I can do science me" segment of "Brainiac", I will cut to the answer straight away: Nope! Is not doable.
Morning after analysis:
Did the resistance rise there for a few minutes? While the brew was cooling down and the resistance was dropping (as predicted), all of a sudden (at 2:52 youtube time) the R starts to rise again! From 184 kOhm to 275 kOhm (at 4:20). There was a small reduction of fluid (when I sipped a bit of tea out) and therefor a reduction of contact area between electrodes and tea, but that did not seem to have a significant long term effect.
Would further research in a more controlled environment be warranted? 8-)
I was thinking that the temperature would be more significant than the selenity of the water from the tea, just because hotter water molecules are more excited and will transmit better.
I noticed that as well when testing the coffee machine. I got 1-2 VAC when the machine was warming up, but when hot water started to come out, and back into the reservoir (because I had the door open) the voltage went up to around 20VAC.
Might be a cheaper way to measure water temperature. Ah, but then there’s the question of how pure the water is. What impurities are in there. Etc. Etc. Etc.
Would you consider a new experiment? I think what we need is not a resistance measurement, but a colorimeter measurement.
I have a nifty RGB LED. We shine variuos colours of light through the tea to figiure out what colour it is. Calibration is performed by leaving the tea in the water until it’s the perfect colour.
Hmmm. The difficult bit is that the section of the brewing vessel to which the sensor is attached might not infuse at the same rate as the rest of the beverage, so it would need to be in a state of agitation. Some tea nuts don’t like their tea stirred during the brewing process.
I might be a tea semi-nutter. I do not stir my tea while brewing either. Outside the lab as well. But I will not drain the tea from the leaves and drink it straight from the glas as shown. Without a straw.
I also believe the colour of tea to be the worst kind of indication for taste. And indeed, the color of black tea stays near the leaves without stirring.
So far I have these two retries in mind:
add a temperature sensor and compensate the dropping resistance against the known effects of dropping temperature
investigate further on the “sudden” rise in resistance halfway through the process, this could be tea related.
We need a baseline experiment for just plain hot tap water cooling down in either case.
Re-boiled water It might be worthwhile measuring the amount of dissolved oxygen in teh water. I know tea-nuts who would never dream of using reboiled water because the oxygen boiled out of it changes the flavour.
There’s also the issue of different types/colors of tea.
I’m an herbal nut, so my tea can go from dark cranberry, to neon orange, to light green. It depends on what I’m brewing. So we would need to tell the proc what kind of tea we are brewing.
Different types of tea shouldn’t be a problem as the machine would employ a robot arm to select from a stored range of teas based on the user’s choice. So each tea could have a preset. Bonus points for the arm.
And that site should make their brewing howto machine readable too!
And and and and the sugar preference of the user could be automated using an rfid chip implanted in Zanthess and her household. Or better: through a glycemia measuring thingey… Just remove the bandaid for a sec and press against the robot.
