About trees & olive oil
Initially, soap was made only in households, not in small or large industries. It was used to cover domestic needs and for cleaning purposes. They used olive oil and cooking oil residues, adding water, potash and salt as set out below: 4 'okkas' of water, 4 'okkas' of oil and one 'okka' of potash (1 'okka' is 1,283 grams).
In the first soap manufacturing industries, large heated boilers and a mixture of oil and soda solution were used. Then, the boiler contents were emptied into the dryer and the liquid mass was poured onto wooden floors or crates in order to cool and take a solid form. At the end, they cut, stamped and packed the bars of soap.
Olive-kernel oil production and olive oil refineries.
In the 1870's, the production of olive-kernel oil begun, i.e. oil that comes from olive kernels. Olive-kernel oil was used in soap manufacturing, olive waste production and olive-oil refineries. This is where soap paste comes from, which is used in the production of cheap soap.