Many people have food allergies and sensitivities that cause them to have any number of reactions to certain foods and/or food ingredients. Food processing can sometimes make foods more or less allergenic.

The allergens in foods are typically proteins that are stable to heat processing. Because of this, heat-processed forms of allergenic foods often retain their allergic potential. This means that normal cooking techniques won’t impact the allergic potential for most foods. The only exception to this rule is pollen-related allergens found in fresh fruits and vegetables involved in oral allergic reactions. Pollen-related allergens are usually destroyed by heat processing, although the amount of heat processing has not been well documented in most cases.

Other processing techniques have not been thoroughly investigated for their effects on the allergic potential of the resulting products. Fermentation usually fails to eliminate allergens; a good example would be fermented soy foods. Fermented soy products often have a reduced allergen potential, but some allergenic activity is retained.

Ironically, a lot of processing may help. If the protein fraction is removed during processing, the resulting product or ingredient might be safe for consumption because the allergen has been removed. The classic example is the processing of edible oils from peanuts and soybeans. Clinical challenge trials in peanut- and soybean-allergenic individuals have documented that highly refined peanut and soybean oils are safe for individuals with allergies to the source material.

Food allergies and sensitivities definitely change how, what and where a person eats. Processing can play a role in helping to alleviate some of this allergic burden, but it will always be a wise move to avoid foods – even those that are processed – if severe reactions are possible.