Spray emulsions are quite popular in summer because although they have the same lipid phase content they feel much lighter on the skin.
The emulsifier is sucrose stearate which you can use both in cold or hot process. Since we are using amigum as the gum/emulsion stabilizer, we heat the water phase around 30 C for 30 minutes or so. You can proceed immediately and emulsify the oil phase in the water phase as the water phase is still warm or you can wait a while till the water phase reaches RT and then proceed with the emulsification.
These are some of our previous spray formulations with sucrose stearate:
|Peach kernel oil
|Prickly pear seed oil
|Liquid vit C
|to adjust the pH
1- Blend phase A in the main beaker
2- Add sucrose stearate to phase A and blend at RT for about 30 minutes. The emulsifier will swell in the water phase and build a gel.
3- Heat phase A+B to 35 C and disperse and hydrate the amigum at this temperature for 30-45 minutes
4- Blend the oil phase in another beaker
5- After the gum hydration is over you can either immediately emulsify the oil in the water phase or stop heating and wait for the temperature to reach RT. Homogenize the oil phase in the water phase. Usually cold process needs more shear compared to a hot process.
6- Stir for at least half an hour.
7- Prepare a 10% dilution and measure the pH. It was 6,15 in our case. Since our preservative system is independent of the pH we can add it at this point.
8- Add the preservative and the essential oil.
9-Add lactic acid to reduce the pH.
10- Prepare another 10% dilution and remeasure the pH. In our case it was 5,39
11- Take your stability and micro kit samples and fill the rest in a suitable spray bottle.
You can watch the video here
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