$24 million - Self Heating Lattes
It took a California company named OnTech seven years and $24 million to create the self-heating cans, which are activated by pushing a plastic button on the bottom. Water flows into a sealed inner cone filled with quicklime, which is mostly calcium oxide. A chemical reaction heats the coffee to a pleasant 145 degrees in six to eight minutes, the amount of time it might take to order, pay for and receive a latte from a barista.
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