Does vinegar or salt used in processing forbidden items such as pork or wine change their impurity so that they are acceptable? Is processed cheese from unslaughtered animals legal?
Praise be to Allah, the Lord of the Worlds; and blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions.
Alcohol, pork and all other impurities, if their nature and reality are changed completely to another thing and if no trace of them is found, most of the scholars believe that their rule becomes the rule of the thing to which they have been changed.
To add more light on this issue we say the following: scholars differ about whether the impure things become converted and changed completely into pure new things. The Shafiites and Hambalis believe that the rule concerning these things does not change and they remain impure. But these two schools give one exception to this ruling, alcohol. They say that alcohol if it is transformed into vinegar, becomes pure because alcohol is impure only if it causes drunkness; otherwise it is pure. But other impure things are impure in themselves (their nature), so their impurity does not change. The evidence for this is the Hadith, which forbids eating the meat or drinking the milk of the animal that eats impurities.
The Hanafis and Malikites, from their most common view, believe that the impure things that convert into pure ones become pure, as it is impossible to clean these impurities from the things themselves. They say that when the Sharia describes something as impure, it means the thing in its initial form and state. If the same thing gets transformed to a different thing so, its rule is the rule of the new thing not the old one.
The reality of anything changes if any of the components of that thing changes, let alone if all its components are changed. For example, if the corpse a dog or a pig decomposes and dissolves in a salina, the salt to which it changes is no longer the flesh and bones which are forbidden. This is the opinion of Ibn Taymiyah and his disciple Ibn Al-Qayyim. So, we believe that anything that melts down and changes completely from its initial state or form into a completely different thing, this last thing is lawful, as this is the opinion of the majority of the scholars.
As for pure things to which an impure component (from a dead animal or a pork ….) is added, they become impure too.
The rule is that any liquid or fluid, which gets in touch with an impure thing, becomes impure too except the pure water. Abu Huraira narrated that the Prophet was asked about a mouse which fell in some ghee and he said: "If the ghee is stagnant take the mouse and what is around it and throw them but if the ghee is liquid do not approach it". (Reported by Imams Ahmad,Abudawood and Nasai)
Allah knows best.
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