Stearin, also known as stearic acid, opens up a whole range of new possibilities in candle making. In this article, you will discover, or rediscover, the countless benefits of vegetable stearic acid. Ready, steady, light!
What is stearin? Definition and history
Stearin is a fatty acid that was once derived from animal fat; today, stearic acid comes from palm or coconut oil.
It has a long track record and has been widely used as an ingredient in candles, soaps, cosmetics and more.
Stearic acid has been an important ingredient in candle making since the Middle Ages, when it was derived from animal fat. It was first used as a substitute for tallow during the Industrial Revolution, thanks to a discovery by the chemist Michel-Eugène Chevreul in the 19th century. Its use became widespread after the Second World War because of its high melting point.
It is an additive that can save you from a whole host of problems by making your wax more opaque and harder, or by increasing your candle's burn time.
Stearic acid vs palm wax
Stearin (or stearic acid) and palm wax are both solid at room temperature and are used as ingredients in a range of products, such as cosmetics, food and candles. There are, however, a few key differences between the two.
Stearin is derived from vegetable oil, usually palm or sunflower oil. It is a white, creamy product used as an emulsifier to help blend the ingredients in cosmetics and food products.
Palm wax, on the other hand, is made from palm oil, usually obtained by hot-pressing palm oil seeds. It is solid at room temperature and is often used in cosmetics to add texture and stability.
In practice, stearin is used for its emulsifying properties, whereas palm wax is used for its texturising and stabilising properties. These are important factors to bear in mind when choosing your ingredients.
RSPO certification and vegetable stearin
More recent research has led to an RSPO-certified natural alternative, a guarantee of sustainable production that is beneficial economically, environmentally and socially. Stearin can now be made from plants rather than animal fats, eliminating its negative impact on the environment and on consumer health. So there is currently no health risk or contraindication to using stearin, and it has no effect on how the candle burns. Not bad, right?
What does vegetable stearic acid do in a candle?
Stearin is a wax additive used in candles to help them burn more evenly and with high thermal stability. Stearin has a melting point of 62°C. One of its distinctive features is that its softening point and melting point are almost identical (by comparison, there is a 15°C gap between the two for paraffin).
A candle made from a blend of paraffin and stearin will burn longer than a pure paraffin candle.
In short, stearin:
- Increases a candle's burn time.
- Takes colour very well and makes colours more intense.
- Makes wax more opaque.
- Lets you make moulded candles (100% stearin).
- Helps you make scented wax melts (100% stearin) with a really strong scent throw.
- Improves scent throw (at 5 to 10%) when blended with soy wax.
- Makes the candle harder, which prevents small cracks.
At a higher dose, you can make the wax opaque, and if you push it much further, the surface may start to crystallise.
Video tutorial: sand wax for candles and wax melts
Using vegetable stearin as your main wax
Stearin has some interesting properties: you can create a “crystal” effect (provided you use a larger wick) with lower proportions than recommended and, conversely, achieve much more intense colours with higher proportions.
Stearin can also be used as a wax on its own, without any additives, whether for container candles, moulded candles or even sand wax melts.
But be careful! We recommend using only polycarbonate or glass moulds with stearin.
