Dry-cured ham thickness is a limiting factor for its sanitization by E-beam treatment

Abstract

This work aimed to optimize the E-beam treatment of whole-boned dry-cured hams to reach the food safety objective for Listeria monocytogenes. According to the zero-tolerance criteria in the USA and China, 2.39 decimal reductions are required. Boned hams were grouped by their thickness in clusters A (≤ 7 cm) and B (> 7 cm). All of them were contaminated with Listeria innocua as a surrogate of the pathogen. The inoculum (approx. 107 cells) was placed in the space before occupied by the bone. Then, bilateral treatments at 1 and 2 kGy were applied to A and B clusters, respectively. Listerial load reductions higher than 2.39 log colony forming units (CFU) were observed in the innermost part of the pieces. The absorbed doses by the treated hams were < 3 kGy, avoiding the radiation over-exposure that could compromise their sensory quality. Therefore, taking into account the thickness of whole-bone ham pieces could optimize the sanitization effect of the E-beam treatment