Forbidden to you (for food) are: dead meat, blood, the flesh of swine, and that on which hath been invoked the name of other than Allah. that which hath been killed by strangling, or by a violent blow, or by a headlong fall, or by being gored to death; that which hath been (partly) eaten by a wild animal; unless ye are able to slaughter it (in due form); that which is sacrificed on stone (altars); (forbidden) also is the division (of meat) by raffling with arrows: that is impiety. This day have those who reject faith given up all hope of your religion: yet fear them not but fear Me. This day have I perfected your religion for you, completed My favour upon you, and have chosen for you Islam as your religion. But if any is forced by hunger, with no inclination to transgression, Allah is indeed Oft-forgiving, Most Merciful. 

[Al-Maeda 5:3]


When you enter a restaurant, make sure they have a Halal certificate. The least you can do is ask the Management. Some restaurants who do not have a certificate, claim to be Halal. Their meat might be Halal but they may also serve Pork. I personally do not prefer eating at such places as their kitchen equipments used for Haram foods have high possibility of getting mixed with Halal foods which eventually make your dish Haram. I bet you do not want to take that risk. When you buy Chicken or Meat or any thing similar, mention you need it Halal. When you buy Packed food or drinks, look for the Halal sign. If not make sure its 100% vegetarian. Or check the Ingredients. Certain ingredients have codes. Most of the codes are Halal. You can make a note of the Haram ingredient codes alone and keep them handy. The rest are Halal.

Name: E120
Ingredient Name: Cochineal, Carminic acid, Carmines
Category: Colouring
Status: Haram
Description:
Colourant, made from crushed insects. This popular colorant is used to impart a deep red shade to fruit juices, gelatins, candies (e. g. red smarties), shampoos. When used as a food additive, the dye must be labelled on packaging labels. Sometimes carmine is labelled as E120. An unknown percentage of people have been found to have allergies to carmine. Natural carmine dye used in food and cosmetics is unacceptable for Muslims because the dye is extracted from insects.
Name: E111
Ingredient Name: Orange GGN
Category: Colouring
Status: Mushbooh
Description:
It is also known as alpha-naphthol orange. It is currently delisted in Europe and USA, as toxicological data shown it is harmful.
Name: E121
Ingredient Name: Orcein, Orchil
Category: Colouring
Status: Mushbooh
Description:
Orcein is a reddish-brown dye obtained from orcinol (a crystaline compound derived from the lichen) by the action of aqueous ammonia and air. Orchil is a purple/blue dye. They are banned throughout the EC.
Name: E125
Ingredient Name: Scarlet
Category: Colouring
Status: Mushbooh
Description:
A red azo dye used as a food dye. It usually comes as a disodium salt. It is permitted in fruit peels and maraschino cherries.
Name: E126
Ingredient Name: Ponceau 6R
Category: Colouring
Status: Mushbooh
Description:
Red coloured food dye. Very little is known about this dye.
Name: E130
Ingredient Name: Indanthrene blue RS
Category: Colouring
Status: Mushbooh
Description:
Indanthrene is a blue dye, the compounds and derivatives of which are used as vat dyestuffs.
Name: E152
Ingredient Name: Black 7984
Category: Colouring
Status: Mushbooh
Description:
A brown-to-black synthetic diazo dye. It usually comes as a tetrasodium salt. When used as a food dye, it has E number E152. It is also used in cosmetics. Its use is discontinued in USA and EU since 1984. It is currently delisted and not used anymore both in European Union and USA. It is also not permitted in Australia and Japan. It appears to cause allergic or intolerance reactions, particularly amongst those with an aspirin intolerance. It is a histamine liberator, and may worsen the symptoms of asthma. It is one of the colourants that the Hyperactive Children’s Support Group recommends be eliminated from the diet of children.
Name: E160a
Ingredient Name: Alpha-carotene, Beta-carotene, Gamma-carotene
Category: Coloring
Status: Depends
Description:
Orange or yellow plant pigments, found mainly in carrots, green leafed vegetables and tomatoes, which the human body converts into Vitamin A’ in the liver. Can be commercially manufactured in the laboratory but beta-carotene, with some alpha-carotene and gamma-carotene present, is normally extracted from carrots and other yellow or orange fruits and vegetables with hexane. Used in butter and soft margarines, coffee sponge cakes, milk products and soft drinks. Please be aware that some manufacturers use gelatine as a stabiliser. With the move away from porcine and bovine gelatine this is likely to be fish gelatine.
Name: Alcohol (alcohol beverages)
Status: Haram
Description:
All sorts of alcohol are strictly not permissible for consumption in Islam whether it is alot (e.g. beverages) or a bit (present in food for flavourings).
Name: Animal Tissue Extract
Status: Haram
Description:
We must consider it haram if no indication or label specifying it from a halal source (zabihah animal, fish)
Name: Alanine
Status: Mushbooh
Description:
A crystalline water-soluble non-essential amino acid. Any protein-containing food such as meat, poultry, fish, eggs or dairy products is rich in alanine.Some plants also contain alanine.It is important to determine the source of alanine.
Name: Aspartic Acid
Status: Mushbooh
Description:
DL & L Forms; As its name indicates, aspartic acid is the carboxylic acid analog of asparagine.Please consult the manufacturer for details.Until proven otherwise the ingrediant is mushbooh.
Name: Animal Fat
Status: Depends
Description:
Animal fats are fats obtained from animal sources, including:blubber, cod liver oil, lard (pork fat), tallow (beef fat), schmaltz(chicken fat).Lard is haram in any case.As for other sources of animal fat they must come from a zabihah animal.Fish oil is also halal.
Name: Animal Shortening
Status: Depends
Description:
Shortening is a type of fat that is solid at room temperature, and is used for making many baked foods. Animal shortening, such as lard, must be avoided.Shortening from zabihah animal is halal
Name: Artificial color
Status: Depends
Description:
It Adds colour to the food product.In its dry powder or granular form it is halal.However liquid colours have vegetable oil or glycerin added.Glycerin of plant source is halal.Some natural food colours are as follows: Caramel coloring is found in Coca-Cola and other cola products. It is made from caramelized sugar. Annatto is a reddish-orange dye made from the seed of a tropical tree. Chlorella is green, and derived from algae. Cochineal is a red dye derived from cochineal insects.
Name: Artificial Flavors
Status: Depends
Description:
Artificial Flavors are usually made from chemical and synthetic raw material. For Halal artificial flavor the synthetic raw material has to be Halal and solvent should not be alcohol.Artificial flavours made from haram raw material(e.g alcohol used as a solvent) is haram.
Name: Aspic Savoury
Status: Depends
Description:
savoury clear jelly prepared from a liquid stock made by simmering the bones of beef, veal, chicken, or fish. The aspic congeals when refrigerated by virtue of the natural gelatin that dissolves into the stock from the tendons; commercial sheet or powdered gelatin is sometimes added to ensure a stiff set. Aspic is used to coat and glaze foods such as cold meats and fish.Doubt arises where the jelly is prepared from the stock obtained from non-zabihah animal.