Wa `alaykum As-Salamu wa Rahmatullahi wa Barakatuh.
In the Name of Allah, Most Gracious, Most Merciful.
All praise and thanks are due to Allah, and peace and blessings be upon His Messenger.
In this fatwa:
1- Islam permits Muslims to eat what is good and lawful, and orders them to avoid what is bad and harmful.
2- The items which carry the letter “E” and a string of numbers are additives.
3- Additives are more than 350 compounds, and could be preservatives, coloring, flavorings, sweeteners, etc.
4- Any foods or drinks that contain any of these ingredients remain halal and permissible for the Muslim’s consumption.
In response to the question you raised, the European Council for Fatwa and Research issued the following Fatwa:
The items which carry the letter “E” and a string of numbers are additives. Additives are more than 350 compounds, and could be preservatives, coloring, flavorings, sweeteners, etc.
These are divided into four groups according to their origin:
First: compounds of artificial chemical origin
Second: compounds of vegetal origin
Third: compounds of animal origin
Fourth: compounds dissolved in alcohol
The ruling on all these compounds is that they do not affect the status of these foods being halal, due to the following:
The first and second groups are halal because they originate from a permissible origin and no harm comes from using these items.
The third group is also halal because the animal origin does not remain the same during the process of manufacturing.
It is transformed radically from its original form to a new clean and pure form through a process called chemical transformation.
This transformation also affects the legal ruling on such ingredients. Therefore, if the original form was unclean or haram, the chemical transformation changed it to another ingredient that requires a new ruling.
For instance, if alcohol changed and was transformed to vinegar, then it does not remain haram but carries a new ruling according to the nature of the new product, which is halal.
As for the fourth group, these items are usually colorings and are normally used in extremely small quantities that dissolves in the final product form, which deems it an excused matter.
Therefore, any foods or drinks that contain any of these ingredients remain halal and permissible for the Muslim’s consumption.
We must also remember that our religion is a religion of ease and that we have been forbidden from making matters inconvenient and hard.
Moreover, searching and investigating into such matters is not what Allah or His Messenger (peace and blessings be upon him) ordered us to do.
Allah Almighty knows best.
Excerpted, with slight modifications, from: http://www.ecfr.org