The easiest answer is yes and no. It depends on what you are making the candles out of, as well as how you are introducing the flavor to the candle wax. In crucial moments that’s exactly what we do. We introduce a chemical component into another substance that causes it to change its fundamental properties or behavior somehow.
If you’re using a food flavoring oil, it is best to add it to the melted wax before you pour it into the candle mold. If you add the oil after the candle has been poured, the fragrance may not distribute evenly. You can also mix some of the flavor oil with beeswax or paraffin to help it distribute through the wax better.
Also, you can add other ingredients to improve the distribution of your flavor oil such as vybar or stearic acid. You’ll probably want to experiment with different quantities before adding too much to your candle. Too much could prevent it from solidifying properly and/or leave soot on your glass. You may find that you don’t need to add any at all, which is what would happen when adding something like chocolate.
To see if the food flavoring oil has been distributed evenly, use a blacklight to check for soot on the glass… If there are no spots glowing under the black light, then your candle should be fine.
When making candles out of soy or paraffin wax, using a natural flavoring oil is not recommended. If you want to experiment with this, get an inexpensive pillar candle and melt it down. Drip some flavored oil into the melted wax to see if it will distribute through the mixture. If it does then add your melted wax to a container of cooled, cleaned melted soy wax. Unfortunately, if your candle doesn’t distribute the flavor oil throughout the wax, you will have to make a whole new batch of pillar candles and start from scratch.
In addition to adding food flavoring oils to melted candle wax, they can also be used by mixing them with skin-safe cosmetic glitters. Then sprinkle the glitter on top of the candle as it is cooling. The glitter will stick to the surface and give off a pop of color as well as a nice smell.