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Soapnut Liquid Preservatives - Soapnuts
Soapnuts can be used to make a liquid cleaner as seen in the recipe HERE. This liquid cleaner will naturally ferment in a very short time if not treated with a preservative.
Soapnut liquid concentrate (or soapnut 'juice', if you like) has approximately a 2 week shelf life on the kitchen bench, or at least a month in the refrigerator.
The addition of an antibacterial oil, such as eucalyptus oil, will extend the shelf life further still.
We have also had great success with citric acid (available easily from supermarkets, or at our Online Store), just use 1 teaspoon per litre. Dissolve the citric acid crystals into 2 tablespoons of hot water, then stir into the strained soapnut liquid.
We have recently started using potassium sorbate as a preservative, and have found this to be even better than citric acid, and more economical.