Peanut processing method may reduce risks for allergic consumers

Researchers have investigated the use of enzymatic treatment to reduce peanut allergens in peanut kernels, using the two major peanut allergens Ara h 1 and Ara h 2 as markers to measure the effectiveness of the process. While no consistent results were obtained for raw peanut kernels, the results are promising for roasted peanut kernels.

In the roasted kernels, enzyme treatment increased protein solubility so the proteins could be extracted more effectively. Results showed that under optimal conditions, enzymatic treatment with alpha-chymotrypsin or trypsin enzymes for 1 to 3 hours was able to effectively reduce the allergenicity of Ara h 1 and Ara h 2 in roasted peanut kernels by up to 100%. Blanching of kernels enhanced the effectiveness of enzyme treatment in roasted peanuts but not in raw peanuts.

According to the researchers, the optimum treatment conditions for roasted peanut kernels was 5 minutes of blanching prior to incubation of peanut kernels in 0.12 per cent enzyme for 3 hours. At the end of such treatment, there was no detectable presence of Ara h 1 and Ara h 2 in soluble peanut protein extracts using ELISA methods.

If this method can be shown to reduce the actual allergen potential of roasted peanuts in human subjects, it may represent an opportunity to treat peanuts post-harvest to reduce the risks of cross-contact with peanut allergens throughout the supply chain.

Reference: Yu et al. 2011. Food Chemistry. doi: 10.1016/j.foodchem.2011.01.074