Halal food is food that is permissible for Muslims to consume as outlined in several verses in the Quran. Muslims around the world accept the Quran to be the book of perfect direction and bearing for humankind and believe the Quran to be the last disclosure of God. In Islam, all foods and beverages are halal except for those that were explicitly forbidden in the Quran as listed below:
Alcohol and other intoxicants such as narcotics
Dead animals that were not slaughtered (Al-Maitah)
Meat that were slaughtered for idols
All carnivores with teeth such as lions and tigers
All winged creatures which have claws, for example, birds of prey, hawks, vultures, falcons and so on
Domesticated donkeys, mice, scorpions, snakes, frogs
Any animal that has died (except fish and sea creatures) before being slaughtered in the Islamic manner
Eating or drinking the milk of the animal which feeds on filth
In order for the food or drink to be halal, it must also fulfill the following parameters:
It does not contain anything which is haram in shariah law (as outlined above)
It was not prepared, processed or contaminated with anything haram
It was not prepared, processed, transported or stored using any facility that is contaminated by anything haram.
It does not contain najis (unclean) material according to shariah law
It must be safe for human consumption, non-poisonous, non-intoxicating or non-hazardous to health.
It must not be prepared, processed or manufactured using equipment that were contaminated with najis or haram foods according to shariah law
The meat(s) must be slaughtered as per Islamic rites
Further reading: What makes Meat Halal?