Autoclaved Peanuts Reduce IgE Binding, Improve Tolerability, With Casey Cohen, PhD

Heat- and pressure-based food processing is not new to allergy research, but new data suggest it may meaningfully alter peanut allergenicity in ways that traditional cooking cannot. In a recent interview with HCPLive, Casey Cohen, PhD, of McGill University, discussed findings from a study demonstrating that autoclaving peanuts, a process combining high temperature, pressure, and moisture, substantially reduces immunoglobulin E (IgE) binding and improves oral tolerability in individuals with a peanut allergy.

“The way people eat peanuts is often roasted peanuts if they're eating peanut butter or just roasted peanuts,” Cohen said. “Or sometimes they boil peanuts in different places of the world, often in Asia. Autoclaving is rather untraditional…the process of autoclaving is used for sterilization. What we found is that it's actually changing the proteins in a different way. It's not just using heat, but the presence of water is changing them differently. It’s actually taking these proteins, breaking them down, not completely, but enough, where we have a lot of fragments, and we think that that is what is introducing different forms of peanut proteins to the immune system. That is not happening with say, boiled or roasted peanut.”

The study evaluated how autoclaving peanuts at 130°C and 2.4 atmospheres for 30 minutes alters peanut proteins compared with raw or roasted preparations. Using mass spectrometry-based proteomics, the investigators showed that autoclaving extensively fragments major peanut allergens, including Ara h 1 and Ara h 2, and completely degrades Ara h 8. These molecular changes translated into a 74% reduction in peanut-specific IgE binding in sera from highly allergic patients compared with raw peanuts.

Clinically, the effects were notable. In skin prick testing of 41 peanut-allergic participants, autoclaved peanut extract produced significantly smaller wheal sizes than standard commercial extract (median 5 mm vs 10 mm; P <.001). Although responses were heterogeneous, patients with the greatest wheal size reductions tended to have lower IgE levels to peanut (P <.05) and allergen components Ara h 1 (P <.05), Ara h 2 (P <.01), and Ara h 8 (P <.05), suggesting a potential role for autoclaved extracts in phenotyping peanut allergy risk. However, Cohen said this remains exploratory.

All 10 peanut-allergic participants undergoing an oral food challenge (OFC) tolerated the maximum cumulative dose of autoclaved peanut (444 mg), equivalent to ≥ 1 whole peanut, with only mild to moderate symptoms. In contrast, all participants reacted to blanched peanuts at much lower doses (median 9 mg), often requiring treatment, including epinephrine.

Cohen cautioned clinicians against extrapolating these findings directly to patient practice. Autoclaved peanuts are not ready for home use, nor should patients attempt self-experimentation. It is uncertain whether any patient with a food allergy can tolerate autoclaved peanuts.

“What is more interesting, we believe, is that we can actually use this autoclave peanut as a starting substrate for immunotherapy,” Cohen said. “Right now, a lot of people who are allergic to peanuts severely will have to start with incredibly small amounts of peanuts. It's… smaller than my pinky nail. In that case, it's hard to be consistent. We get a lot of variability, and the peanut proteins themselves are a lot more rigid and [a] lot more likely to induce a more dangerous reaction. By autoclaving the peanuts, we think it'll give us more leeway. We can start at a higher dose of autoclaving peanuts, especially if there's no dangerous symptoms coming with it, and then we can work our way up to maybe, eventually, transfer over to the regular, traditional peanut.”

Cohen has no reported disclosures.

References

Cohen CG, Toscano-Rivero D, Ahmed EA, et al. Autoclaved Peanuts Exhibit Reduced Immunoglobulin E Binding and Improved Oral Tolerability. Allergy. Published online January 6, 2026. doi:10.1111/all.70208