Make sure all utensils, containers, and pots are fully clean. I like to run what I can through the dishwasher to help kill of any bacteria. You can also clean utensils with rubbing alcohol to help clean and dry them.
Weigh out the water or aqueous phase ingredients. You should use distilled water to prevent adding any unwanted pathogens or minerals. You can substitute floral waters or other distillates for the distilled water.
Heat the water (or aqueous phase ingredients) to around 70º-75ºC/160º-170ºF. We are heating the water so that it will be around the same temperature as the oil(s) so that the emulsification process can take place correctly.
While the water is heating, begin weighing out your oil(s) and wax. I find that the best way of doing this is to tare the scale with a small double boiler pot on the scale, add the oil(s) to the pot until you reach the required weight, and then tare again before adding other oils or the emulsifying wax.
Just this week I made a batch of sweet almond oil lotion, and a lotion made with mostly coconut oil and a touch of hemp seed oil. I assumed that the coconut oil lotion would be a bit thicker, especially now that it is still cold outside, but both lotions were pretty similar in texture. Use your oil(s) of choice. Soon I'll write a post about some of the qualities of certain oils so you can better choose oils that will best serve your skin type.
Heat the oil and wax over a double boiler, stirring until the wax has completely dissolved. You are aiming to get the oil to around 70º-75ºC/160º-170ºF, but the exact temperature isn't super important.
Some people advocate using a "heat and hold" method, where you heat both the oil phase and aqueous phase ingredients separately, and hold them at around 70º-75ºC/160º-170ºF each for around 20 minutes, before bringing them together. Some say it helps with the emulsification process. Others say it helps ensure killing off all possible pathogens. I personally don't use the "heat and hold" method myself, and until now haven't had any problems with lotions separating or going bad more quickly. This is a topic that would warrant a full post, but I don't want to go into it right now, so I'll leave you with this post with some arguments against it. If you are having problems with lotions separating after several weeks, it is something that you could try.
Add the hot water to the hot oil mixture and whisk the ingredients together. As the mixture cools, the liquid will get thicker and more opaque. If you are having issues with the emulsification process, it could be a problem with either the water or the oil(s) having cooled too much. This can be remedied by heating the mixture over a double boiler and whisking until the mixture is well emulsified.
Allow the mixture to cool slightly.
Meanwhile, as it cools, you can test the pH of your mixture. Leucidal allows for a wide pH range of 3-8, but Rokonsol works as a natural, mild preservative only when the pH is below 5.5. Your lotion will very likely be slightly higher than that.
Add a few drops of lactic acid, if needed for your preservative, and test the pH again. For Rokonsol, once it is lower than 5, you are ready to continue. With Leucidal it is likely that you won't need to add any acid.
Once the mixture has cooled and thickened, you can add in the preservative and any delicate, heat sensitive ingredients like essential oils.
Mix together all ingredients, and pour the mixture into the final containers. I like to use "airless" containers or silicone tubes because they allow you to dispense the lotion without putting your fingers into a container and contaminating the lotion.
Wait until the lotion is fully cooled to room temperature before capping. This is just a precaution to keep condensation from forming inside the container and floating on top of the lotion to prevent mold from forming. In any case, it's a good idea to shake the containers well once capped to ensure any humidity from possible condensation is incorporated into the rest of the lotion.
Enjoy your lotion.
Natural preservatives like Rokonsol and Leucidal give the final product a shelf life of around 3 months. I make lotion in small batches so that I use it up before then. It's a good idea to date your containers so that you know when you should toss the remaining lotion and make a new batch. (Once you get the hang of it, you can easily make a new batch in less than half an hour, so this isn't really an issue!)
Recipe printed from Oh, The Things We'll Make! Blog. https://thethingswellmake.com/make-simple-basic-homemade-lotion-customize-skin-type/