Title: Influence of pH, temperature and storage condition on survival and growth of Salmonella Enteritidis in membrane processed liquid egg white Authors
Submitted to: International Food Technology Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: February 9, 2012
Publication Date: June 25, 2012
Citation: Mukhopadhyay, S., Phillips, J.G., Ukuku, D.O. 2012. Influence of pH, temperature and storage condition on survival and growth of Salmonella Enteritidis in membrane processed liquid egg white [abstract]. International Food Technology Meeting Abstracts. IFT Annual Meeting. June 25-28, 2012, Las Vegas, NV. 1:1. Technical Abstract: Study was conducted to establish the effects of variations in liquid egg pH and membrane processing temperature on the removal and growth of Salmonella Enteritidis in liquid egg white (LEW) filtered by microfiltration (MF) process. Storage condition variations influence on growth of Salmonella in the membrane separated LEW was also examined. Pretreated and pH adjusted (pH 6, 7, 8, and 9) unpasteurized LEW from local egg breaking plant was inoculated with a five strain composite of Salmonella enterica serovar Enteritidis at a level of approximately 1.00E+07 colony-forming units (CFU)/mL and microfiltered using a ceramic membrane with a nominal pore size of 1.4 micron, at an optimum crossflow velocity of 6 m/s, at either 25C or deg 40C followed by storage at 4C or 10C. Variations in membrane processing temperature, LEW pH, or storage condition affected Salmonella Enteritidis population in membrane separated LEW significantly (p less than 0.05). Temperature had greater influence on Salmonella spp. reduction compared to pH. Maximum reduction of Salmonella and background microflora in LEW by MF was observed at 40C and pH 8 and 9. However, LEW pH had significantly greater influence on permeate flow than temperature. Average permeate flux increased by about 180 percent when pH of LEW was adjusted from 8 to 6 at 25C whereas the mean flux increased by only about 18 percent as temperature increased to 40C from 25C at pH 6. Irrespective of MF process condition, Salmonella populations in filtered LEW remained quite stable at a level of 0.01 – 0.55 log10 CFU/mL, at 4C storage and although Salmonella population was slightly higher at 10C storage, no major outgrowth was observed. There is a need for effective marketable technology alternative to thermal intervention to control Salmonella in liquid eggs. The results from this investigation would be highly beneficial for liquid processing industries.