Some scholars see that the addition of a small quantity of forbidden foodstuff that went through chemical changes so as not to exist on their own acquiring new description, will not affect food permissibility.

Food Containing Small Quantities of Forbidden Products

Similar Questions 

· Eating food that contains small quantities of what is forbidden to eat.
   · Food that includes a small quantity of forbidden foodstuff.

The Issue

Some types of food contain some forbidden foodstuff, such as extracts from the flesh of swine. Most of these are enzymes that help to preserve the food, but still they are extracted from the bones or fat of pigs. Are such foods permissible to eat? 

Ruling

If these substances are small in quantity and they get changed through chemical reaction so as not to exist on their own, acquiring a new description or name, then their status changes and that will not affect the permissibility of the food or drink. This is the view of the late Shaikh Muhammad ibn Uthaymeen and a number of contemporary scholars.[1]

Evidence

1. The Prophet’s companions used to eat cheese made by the Zoroastrians who used rennet taken from animals they had slaughtered. It is well known that their slaughtered animals are forbidden for Muslims to eat. However, using such rennet did not affect the taste or smell of the cheese, but was only used to make cheese. 

2. A rule that is implemented by scholars is that when an impurity goes through transformation, its status changes. Examples include wine that becomes vinegar, an impurity that catches fire and is reduced to ashes, or an impure animal such as a dog or a pig falling into a salt facility and becoming a part of the salt product. In all such cases, the substance is changed and its name is also changed. As such, its status is changed, because the status depends on the reason that gives it such status. When the reason does not apply, the status changes.  

Sources

· Fatawa al-Aqaliyyat al-Muslimah, by a group of scholars.
   · Abdullah Ben Bayyah, Sina[at al-Fatwa wa Fiqh al-Aqaliyyat.