What causes an allergic reaction to certain types of natural on processed foods such as peanuts?

Along with peanuts and shellfish, tree nuts are one of the food allergens most often linked to anaphylaxis — a serious, rapid-onset allergic reaction that may be ... to determine the presence ofallergen-specific immunoglobulin E, an antibody that binds to allergens and triggers the release of chemicals that cause symptoms. 
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Usually they are affected by a certain PROTEIN in a food or ingredient, such as peanuts and/or shellfish.

Glucose, also called grape sugar, blood sugar or corn sugar, is among the simplest and one of the primary naturally occurring sugars. produced naturally by plants as the primary photosynthesis product, it is heavily used by living beings as a main energy source and is necessary for cellular respiration. chemically, it is a monosaccharide carbohydrate and serves as a building block for complex sugars like starch.