- 1). Make single-use batches. This may not be practical for all products, but if you make something like a hair mask that is used only every week or two, it is best to make it fresh on the day you plan to use it.
- 2). Keep it in the refrigerator. This will keep most ingredients fresh for a week.
- 3). Keep water out of the container. Make sure your hands are completely clean and dry before dipping into a container to avoid contamination.
- 4). Store mixtures in dark, opaque containers to keep out sunlight, which will reduce their shelf life.
- 5). Use antioxidants as a natural preservative. One option is to use 0.15 to 0.5 percent rosemary oil extract in the formula.
- 6). Add 0.5 to 1 percent grapefruit seed extract, which is a natural anti-microbial.
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