A review of food allergies, and new ways to identify them in food

Food allergy is an overreaction of the immune system to certain foods or substances that usually are safe and the production of IgE antibodies is quite evident. This is usually caused by allergic reactions to food proteins that are specific immunological responces. A number of specific clinical syndromes that occur as a result of a food allergy include anaphylactic shock, Asthma and atopic dermatitis associated with food allergies. Food ingredients that stimulate the immunological and cause allergic reactions, are traceble. The detection of allergens in food products can be very difficult. Reactions determined by double-blind placebo controlled food challenges (DBPCFC) range between less than 1 mg and more than 1 g of allergenic protein in 1 Kg/food depending on the food concerned and the sensitivity of selected allergic individuals. Today the major existing techniques, DNA-based identification of parts or components of the fusion protein allergens that each has advantages, disadvantages and different applications. Immunochemical diagnosis usually involves protein-based methods and ELISA is the most famous of this. On the other hand, in DNA-based methods, duplicating a particular piece of DNA is done by use of the heat resistant polymerase and two primers.