Salaam,Is it halal to eat food that was cooked in oil that could have come into contact with oil that has been used to fry non-halal chicken? The restaurant says that 'this can occur during the filtration process for the oil' and that 'every effort is made during oil filtration to keep the oils separate but we cannot guarantee that cross contamination will not occur.' They also explained that they cook food in 'seperate vats that share the same inlet for oil, which goes through a mesh filter as it passes through the filter box. These vats use the same filter box and, as a result, there may be a very small degree of oil to oil contamination. During the filtering process, it's not possible to completely remove all traces of oil in the equipment. It's therefore possible that tiny traces of the vegetable oil used to cook the chicken products may come into contact with the vegetable oil used to cook the fish products.'JazakAllahKhair
All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
As long as there is no firm certainty that this oil has become impure, then the basic principle is that it is pure and that it is permissible to use it.
There is no need for these whispers and delusions. It is enough to act according to the principle, which is purity, unless the opposite is made certain. If there is certainty that something of these dead things has fallen into the oil, then the scholars differed about its ruling. The view chosen by Shaykh Ibn Taymiyyah which we see that it is more lenient to you, is that it is not judged to be impure unless it is changed by the impurity; accordingly, as long as the oil is not changed by impurity, then you may use it and there is no harm on you.
Allah Knows best.
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