An in-depth review of the current scientific knowledge on food allergens testing, covering the major methodologies and techniques used to detect food allergens. Food allergens are a series of agents, mainly proteins, which cause various unpleasant and sometimes clinical symptoms in humans through consumption of foods. Perhaps surprisingly, there are no treatments against food allergies which have been found to be 100% effective. The scope for individual difference in terms of how a person reacts to a given allergen is massive, making it incredibly difficult and complex to try and medicate against allergies.