Typically, the bubbles in beer are created during the boiling process, which requires a great deal of heat and water. To make the process a bit less energy-intensive, the world’s largest beer brewing company, AB Inbev, has created a new low-carbon method for adding bubbles to beer. The technique involves heating the brew to just below the boiling point, then pumping in CO2 or nitrogen to create gas bubbles. By doing this, the company expects to reduce its CO2 emissions by 5 percent.