Preservation of sliced cooked ham at 25, 30 and 37 °C under moderated pressure (hyperbaric storage) and comparison with refrigerated storage

Abstract

The feasibility of hyperbaric storage (HS) to substitute refrigeration as a lower energetic cost alternative to refrigeration, for sliced cooked ham preservation was assessed by using temperatures and pressures ranging 25–37°C and 25–150MPa for 4 and 8h.At microbiological level, storage at 25°C, 30°C, and 37°C, showed no effect on microbial growth at 25MPa reaching levels similar to atmospheric pressure storage, around 5logCFU/g for both total aerobic mesophiles (TAM) and lactic acid bacteria (LAB). Nevertheless, the storage at 50MPa and 30°C resulted in microbial growth inhibition, resulting in TAM and LAB counts similar to refrigeration, of about 3.8logCFU/g for both the microorganisms. Additionally, the increase of the storage pressure to 100–150MPa resulted in microbial inactivation, leading to microbial loads of almost 1logCFU/g lower than refrigeration. In general, hyperbaric stored sliced cooked ham showed physicochemical parameters similar to the refrigerated samples.In conclusion, these results show that HS at uncontrolled (naturally variable room temperature conditions at 25–37°C) is a promising alternative to refrigeration for cooked ham preservation. To this new preservation technology, no energetic costs are associated throughout storage, compared to refrigeration, needing only energy to generate the pressure and decompress, since no energy is required to maintain the pressure.