Patients will be recruited from the pool of patients referred to the investigators center for evaluation of food allergy. For each tree-nut (walnut, pecan, cashew, pistachio, hazelnut or almond) evaluated, 30 patients (ages 4-45 years old), with allergy to at least one tree-nut will be recruited from the database pool referred to above. Skin prick tests (SPT) and BAT will be performed for all suspected allergens. Sera will be taken and sent to ThermoFisher for IgE and IgG4 binding analysis to purified components. Open OFCs will be performed for each tree-nut, unless clinically contraindicated. The results of the OFC will form the basis to determine the sensitivity and specificity of the component testing. Similarly, 40 patients with suspected sesame allergy will be administered SPT and component analysis for sesame, with correlations to OFC.