Dr. Wani, deep fry oil generally retard bacterial growth. But leads to growth of Clostridium botulinum, which causes botulism, a potentially fatal food poisoning. So, dip fried oil is not helpful at all in soil. Anyway, it does not improve soil organic carbon.

Thanks Dr. Tarafdar.

If we ferment the oil aerobically with pseudomonas culture and then drench it. So every emulsified droplet contain culture, so very less chances to get available nutrient to grow contaminant. what will be the possibility to grow clostridium.?

What else can do with waste oil in farming??