In face of the soil pollution that has changed the taste of vegetables and fruits and may cause cancer, the two engineers found by trial and error that vinegar "extracted from the residues of tree pruning" is a possible solution.
"So my colleague and I decided to produce wood vinegar to help eliminate such problems," Afifi said.
The production, however, was initially hampered by the lack of a special device banned by Israel from entering Gaza. Israel has been blockading Gaza since Hamas violently seized control of the the Palestinian coastal enclave in the summer of 2007.
Despite the odds, the two engineers found a way to make the device with simple tools available, which consists of two iron barrels, one used for decomposition and the other for distillation.
They have also simplified the production procedures by burning the wood to make it decompose into smoke and steam which pass through an iron tube into the other barrel linked to a small tube for distillation, according to Afifi.
"During the production process, we should check the salinity, temperature, and acidity of the produced vinegar through a measuring device, to ensure the validity and feasibility of its use," Ahmed told Xinhua.
"After that, we can filter the distilled vinegar to extract the exhaust and impurities for pure vinegar suitable for fertilizing agricultural land," the engineer added.
Adham al-Basiouny, spokesman of the Gaza agricultural ministry, praised the engineers' wood vinegar research as a useful initiative to help local farmers address their harvest problems, because "the high level of salinity along with soil pollution is one of the major hazards to agricultural crops in the Gaza Strip."
"The product has proven effective, which may lead the ministry to allow the farmers to use it for high-quality agricultural crops free from the problems that harm human health," Basiouny said.