You may find that your handy reliable jar of shea butter has become gritty or grainy and wonder why has this happened? Has this shea gone bad? Is it still good to use?
The quick short answer is the shea has not gone bad, it is still good and it's still good to use. Here's why it happens.
Shea butter and other plant and dairy-based butters are able to stay solid as long as the surrounding temperature is not too warm or hot. These butters have a melting point or melting temperature where the butter will melt and become a liquid oil. Once it's become a liquid oil, it needs to be cooled down to re-solidify, preferably rapidly for best results.
Shea butter has a melting point between 89 and 100 degrees. Shea butter itself is made up of fatty acids that have their own separate melting points. These fatty acids are:
|Fatty Acid||Composition of Shea Butter||Melting Point|
|oleic acid||40-60%||55 - 57°F|
|stearic acid||20-50%||156 - 157°F|
About 85 to 90% of the fatty acid composition is stearic and oleic acids. The relative proportion of these two fatty acids affects shea butter consistency. The stearic acid gives it a solid consistency, while the oleic acid influences how soft or hard the shea butter is, depending on ambient temperature.
When shea butter melts, it becomes oil. It then needs to be chilled or refrigerated to allow it to become solid again. If it sets at room temperature instead, it can become crystallize or grainy. This occurs as the fatty acids with lower melting points solidify faster than those with higher melting points. So gradually cooling the shea butter will result in the fatty acids reconstituting slower or not at all, which is how grains and crystals form.
To remedy this, use a refrigerator or other cool/cold environment. Rapidly cooling the butter helps the fatty acids cool more uniformally and reconstitute faster to become a smooth butter.
Once solid again, try to keep shea butter in a cool place for storage. As a solid butter, shea butter stays solid at room temperature, so it's ok if it's not always refrigerated. However if the room temperature is above 80-85 degrees, then it's too warm.
Also to note, the shea butter is perfectly fine and usable in its grainy and gritty state. You don't have to worry about whether it's starting to turn or go bad. It can be used normally. I personally keep a jar of vanilla whipped shea butter in my car for all seasons. In the winter time, it stays solid and cool to the touch when I apply it. In the summer, depending on how warm or hot it's been, it might be a jar of oil or a jar of grainy shea. I use it either way because I love the scent and I love not being ashy!