Microbial fermentation as a strategy for the abatement of peanut allergens

Although valued for their nutritional content and flavor, peanuts are ranked among the nine major food allergens in the United States, capable of inducing life-threatening reactions mediated by immunoglobulin E (IgE). Ara h 1, Ara h 2, Ara h 3, and Ara h 6 are recognized as major allergens due to the prevalence and structural stability of their epitopes, which make them resistant to digestion and processing. To address these challenges, processing treatments of different natures have been tested (e.g., physical, chemical, and biological) to reduce the allergenic content and create safer and more nutritious nuts. Allergen degradation studies discussed in this paper highlight the roles of endogenous peanut enzymes and microbial metabolites, as well as computational tools useful to model theoretical protein transformation under degradative treatments. Fermentation is emphasized for its multifactorial potential, combining the synthesis of bioactive metabolites by generally recognized as safe (GRAS) microbes with their proteolytic and redox activity to reduce allergenicity in peanuts while improving nutritional and sensory quality. Despite significant progress of these approaches, the development of a viable hypoallergenic peanut product remains elusive. Therefore, potential fermentation enhancers are discussed, including the addition of naturally extracted polyphenols that can alter the structure of peanut epitopes while increasing their proteolytic susceptibility. This review integrates structural insights, physical, chemical, and biological interventions, and computational approaches to provide a comprehensive perspective on peanut allergen reduction. By emphasizing epitope-targeted fermentation and synergistic treatments, we outline directions for developing safer peanut-based foods that balance efficacy, feasibility, and consumer acceptance.