Impact of High Hydrostatic Pressure Treatment on Microbial Communities in Chinese Water-Boiled Salted Duck

Abstract

The objective of this study was to determine the impact of high hydrostatic pressure (HHP) treatment on microbial communities in Chinese water-boiled salted duck (CWBSD) and the synergistic effect of HHP and mild heat treatment. In this work, the bacterial diversity was evaluated by using both a culture-dependent method and denaturing gradient gel electrophoresis. The total aerobic bacterial counts in pressure-treated samples were significantly lower than those in controls, which indicated that HHP could extend the shelf life of CWBSD. Weissella hellenica and Enterobacteriaceae, the predominant bacteria found in CWBSD, were not detected after HHP treatment. On the other hand, Staphylococcus spp. and Bacillus spp. became the predominant bacteria in HHP-treated samples. Moreover, the inhibitory effect was greater at 400 MPa than at 200 MPa combined with mild heat at 40°C. This study investigated the diversity of bacteria in HHP-treated CWBSD, and the information derived from this research may help to understand the bacterial ecology and develop effective HHP treatments to extend the shelf life of CWBSD.

Effect of High Hydrostatic Pressure Combined with Moderate Heat to Inactivate Pressure‐Resistant Bacteria in Water‐Boiled Salted Duck

“…For the inactivation of microorganism in WBSDM treated by HHP, Shen and others () studied the effect of HHP combined with heat on the shelf‐life and the total number of bacterial colonies. Feng and others () determined the impact of HHP treatment on microbial communities in WBSDM, and confirmed that B. cereus and S. warneri became the dominant bacteria in products after treatment. Therefore, in this study, temperature played an important role in pressure inactivation of pressure‐resistant bacteria in WBSDM.…”

“…WBSDM is a highly popular meat product in China, and there is a demand to develop methods to extend its shelf‐life without affecting its quality. Previous studies have shown that HPP treatment can be used to inactivate most microorganisms in WBSDM, except for B. cereus and S. warneri (Feng and others ). Therefore, the optimal treatment of the high pressure combined with moderate heat to inactivate the pressure‐resistant bacteria in WBSDM has been studied here, and any impact on meat quality attributes after the suitable treatment has been determined.…”

“…B. cereus and S. warneri described by Feng and others () were used in this study. Each strain was cultured in LB culture medium (LB, Land Bridge Company, China) at 37 °C for 20 h, until it reached the stationary phase.…”

“…However, different microorganisms may have different degrees of resistance to HHP treatments, due to a broad sensitivity range among different microbiological species (Considine and others ). Previous studies on HHP‐treated WBSDM (Feng and others ; Shen ) have shown that high hydrostatic pressure treatment can effectively be used as a postlethality process. It was found that Bacillus cereus and Staphylococcus warneri became the dominant bacteria in the products affecting the shelf‐life during storage after HHP treatment.…”