If you’re at all familiar with the specialty coffee industry, chances are you’ve come across many a Hario product. Hario has a broad range of items, ranging from kettles and hand grinders to pour over drippers, teapots, syphons, and servers, with many of these products featuring Hario’s famous heatproof borosilicate glass.
If you were to go and get a glass of water, the glass that you drink from is more than likely to be formed out of silicon dioxide, sodium oxide, and calcium oxide – or, silica, soda, and lime. If you dropped that glass on the ground, it would most likely shatter, and if you dropped it into a very hot sink of water, it might even crack from the change of temperature. Borosilicate glass does not have these characteristics, which makes it a perfect material for glass products in the coffee industry.
Borosilicate glass has an added ingredient called boric acid, which makes up 5% of the glass mixture. What this essentially does, is it creates a glass product that has an extremely high resistance to heat and severe temperature changes. It also creates glass that has an extremely high resistance to chemicals, meaning that the glass will not corrode if it comes into contact with harsh chemicals. For this reason, borosilicate glass is commonly used for cookware, LED lights, scientific lab equipment and even the storage of nuclear waste.
HOW IS IT MADE?
Hario’s heatproof borosilicate glass goes through the following process of manufacturing:
SO WHY USE IT IN THE COFFEE INDUSTRY?
Unlike regular glass, borosilicate glass does not expand with changing temperatures, it is not affected by acid or alkali, and most importantly, it does not transfer odours or colours. This means that the flavour of coffee is not compromised. This is due to the melting process of the glass, where once the glass is melted, the surface is smooth and non-porous, with no gaps into which dirt, odour, air, and liquid can enter.
Hario glassware can be used both in the microwave and the dishwasher (unless hand-painted), due to its high melting point of 288°C, and it is more likely to snap or break into large chunks rather than shatter, making it a safer option to clean up if it does get dropped.
When you choose to buy Hario products, you’re choosing to support an environmentally-friendly company. Hario makes their products from 100% raw and natural materials, and uses electricity instead of fuel for their melting process, eliminating the need for chimneys to release dust and smoke into the atmosphere.