Performance Evaluation of a Jug r 2-Targeted Real-Time PCR Assay in Processed and Commercial Food Matrices: Implications for Allergen Risk Management
Applied Food Biotechnology,
Vol. 13 No 1 (2026),
7 décembre 2025
,
Page 1-13 (e21)
https://doi.org/10.22037/afb.v13i1.52730
Résumé
The reliable detection of walnut allergen contamination in processed foods is challenging due to matrix complexity and DNA degradation caused by thermal processing. In this study, the operational performance of a TaqMan-based duplex real-time PCR assay targeting an ultra-short region of Jug r 2 was evaluated for its applicability in complex food matrices and heat-treated samples. The assay incorporated an internal amplification control to monitor DNA extraction efficiency and PCR inhibition. The assay successfully detected walnut DNA across all spiked formulations (cookies, soup, ketchup, and cocoa). The observed matrix-dependent Ct shifts remained within acceptable limits, reflecting moderate inhibitory effects, with the highest delay observed in the soup matrix (+4.52 cycles). Thermal processing, especially autoclaving, (121°C, 20 min), induced significant DNA fragmentation, resulting in an average Ct shift of +4.78 cycles; however, the Jug r 2 target remained consistently detectable across all replicates due to the robust 88-bp short amplicon architecture. The successful detection of walnut DNA in commercial food products further validated the practical applicability of this assay for routine allergen surveillance in real food samples. Overall, this optimized duplex platform demonstrated high robustness, matrix tolerance, and commercial feasibility for the detection of walnut-derived material in processed foods, offering a practical tool for allergen monitoring, label verification, and food safety management.
- Juglans regia
- Walnut allergen
- Real-Time PCR
- Processed foods
- Food safety
Comment citer
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