PULSED ELECTRIC FIELD TREATMENT OF LIQUID WHOLE EGG INOCULATED WITH SALMONELLA ENTERITIDIS

Abstract

The effects of pulsed electric fields (PEF) on the inactivation of Salmonella Enteritidis inoculated into liquid whole egg (LWE) and on the physical properties and the shelf‐life of LWE were studied. PEF processing conditions were 1.2 mL/s flow rate, 200 pps frequency, 2.12 μs pulse duration, 25 kV/cm electric field strength, and 250 μs total treatment time. The PEF processing caused up to 1 log10 cfu/mL reduction in S. Enteritidis population in LWE. The PEF‐treated samples were subjected to heat at 55C for 3.5 min to inactivate the remaining bacteria without denaturing the LWE. The combination of PEF and heat treatments led to a 4.3 log10 cfu/mL reduction in S. Enteritidis population (P < 0.05) and caused no significant change in viscosity, electrical conductivity, color, pH, and Brix, relative to control samples (P > 0.05). The PEF+55C treated LWE samples presented significantly longer shelf‐life at 4C compared with the control and heat treated samples (P < 0.05).

Inactivation of Lactobacillus brevis in Liquid Egg White by Radio-Frequency Flash Heating

“…The survival rate of L. brevis (E. coli) reached four orders of magnitude at 60℃ (69℃). PEF treatment alone showed a 1.0 log reduction of Salmonella in liquid egg white, but a 4.3 log reduction of Salmonella was achieved by combined PEF thermal treatment at 55℃ (Hermawan et al, 2004). The estimated electric field and current density of RF-FH were 450 V/cm and 3.0 A/cm 2 , respectively.…”

Recent Advances in the Application of Non Thermal Methods for the Prevention of Salmonella in Foods

“…Application of PEF (25kV/cm, 250 μs in pulses of 2.12 μs) followed by heat treatment at 55 °C for 3.5 min increased the inactivation of Salmonella Enteritidis inoculated into liquid whole egg from 1 logs to 4.3 logs (Hermawan et al, 2004). The combination treatment had no effect on the color, pH, viscosity and brix of the treated samples and had a longer shelf life in comparison to heat treated samples.…”

Study of short-wave ultraviolet treatments (UV-C) as a non-thermal preservation process for liquid egg products

“…In the United States it is estimated that 2.3 million shell eggs or 1 out of every 20,000 eggs may be contaminated with the pathogen, Salmonella enteritidis Hendrickx, 2006;Lai et al, 2010). Therefore, heat pasteurizations may alter the foaming and emulsifying properties, and therefore degrade the quality and functional properties (both technological and nutritive) of egg products (Gongora-Nieto et al, 2003;Hermawan et al, 2004). In particular, after the typical pasteurization conditions, the egg albumen appears cloudier, more viscous, and requires longer whipping times (Li-Chan et al, 1995;Hou et al, 1996;.…”

“…Moreover, the process parameters are to be designed for the desired level of thermal treatment with minimum damage to the lipoprotein ingredients of the LEPs (Gut et al, 2005). Since thermal treatment has the potential to degrade the nutritive quality and functional properties of egg products, negative effects of high temperature, as denaturation of protein structure should be eliminated (Gongora-Nieto et al, 2003;Hermawan et al, 2004). Two main parameters of LEPs are fundamental for thermal pasteurization processes:…”