When making water-based products for skin application it is important they are neither too acidic nor too alkali, to avoid irritation.  Therefore, the pH needs to be adjusted to a skin compatible level (generally accepted as 5.5) at the end of your products creation.  The crafting phase of our development is when we test the pH level using pH strips.

To test, place one strip into your product to moisten then wipe away any residual product from the paper.  Failing to wipe away a white product such as cream will make viewing any colour changes on the pH strip extremely challenging.  Take careful note of the colour match that indicates what the pH level of your product is.

Your pH may be 5.3 - 5.8 which will mean that your product is within an acceptable range with no adjustments needed. However, if it is outside these parameters an adjustment will need to be made.

To do this you will require one of two solutions depending on your findings.  If you intend on making a few products or even a few batches of the same product, having pH adjusting solutions made up and ready to go are very helpful

If your product is above 5.8 this means it is too alkaline and you will need to add an acid solution to bring the pH back to where it needs to be.  An outline of how to make this solution is listed below.

If your product is below 5.3 this means it is too acidic and you will need to add an alkali solution to bring the pH back to where it needs to be.  An outline of how to make this solution is listed below.

Creating Your Acidic Solution

This is a 50% acidic solution which you can use to bring down the pH of a product over 5.8.
Weigh 20gm demineralized water into a small saucepan.
Add 20gm citric acid.
Heat gently while stirring until dissolved.
Cool to room temperature.
Transfer to a plastic dripper bottle using a small funnel.

Creating Your Alkali Solution

This is a 30% alkali solution which you can use to bring the pH up of a product under 5.3.
Weigh 28gm demineralized water into a small bowl.
White wearing gloves and goggles add 12gm caustic soda and stir gently until dissolved.  This product will heat up by chemical reaction.
Cool to room temperature.
Transfer to a plastic dripper bottle using a small funnel.

Once you have your solutions made up add a drop of the correct adjusting liquid to your product and stir well.  Take a fresh strip and test the pH again (do not use the same strip as the colours will not change to reflect your adjustment). Make further adjustments in line with your findings until you achieve the correct pH level.

If you overshoot whilst correcting, use the other solution to adjust your product back to where you need it to be.

pH is only measurable in products that contain water.  Products such as balms and oils cannot have their pH assessed.