The waste oil produced in the pastry making process can be used as soap. The practice is as follows:
Raw materials: waste oil from home (residual oil after cooking in the kitchen), caustic soda, soap base and water. The price of caustic soda and soap base are very cheap. The price of caustic soda is a bag (about 111g) in 5 yuan, and it is even cheaper if it is wholesale. It costs two or three yuan a bag and can be bought in shopping malls or online. They usually collect waste oil from street fried food stalls.
Tools: a heatable pan, a weighing pan, and molds for making various soaps.
1. filter the waste oil. There are impurities in waste oil. Use gauze or activated carbon to filter out most impurities. If there are many impurities, the color of the handmade soap will be ugly, which will also affect the feel of use.
2. Prepare all kinds of raw materials. Measure 35g caustic soda, 251ml filtered waste oil and 115ml water. This ratio is specially calculated, and if it is higher or lower than this ratio, it is not easy to manufacture successfully.
3. heat the waste oil and add water to caustic soda to stir. Put the soap base and the filtered waste oil into a pan for heating. Since the melting point of the soap base is about 51℃, once the soap base is dissolved, it will be fine. Take out the oil and put it into a container. While heating the waste oil, add the weighed caustic soda into water and stir. Because caustic soda will produce a high temperature close to 91℃ when it meets water, and it will give off heat and smell, you must wear gloves when making it and be in a ventilated state.
4. Mix and stir. Cool the diluted caustic soda liquid to about 51℃, slowly pour it into a container containing waste oil and stir it clockwise. "Just like beating eggs, stir for 15 minutes."
5. pour into the mold for curing. Pour the stirred semi-finished product into the mold, then put it in a ventilated place for curing, and it can be used in a few days. If you want to make soap more beautiful, you can add some pigments or spices.