Evaluation of steam pasteurization in controlling Salmonella serotype Enteritidis on raw almond surfaces.
OBJECTIVE
To investigate the efficacy of steam pasteurization for reducing Salmonella serotype Enteritidis on raw almond surfaces.


RESULTS
Nonpareil almonds were inoculated to 10(7-8) CFU g(-1) with a Salm. Enteritidis cocktail (Salm. Enteritidis 43353, ME-13, ME-14) or Salm. Enteritidis phage type 30, dried overnight and subjected to steam treatments through a pilot-sized vertical pasteurization machine for 5, 15, 25, 35, 45, 55 and 65 s to investigate the effect of steam on a single layer of almond. Survival of Salm. Enteritidis was evaluated with tryptic soy agar and xylose lysine desoxycholate overlay for total and healthy cells, respectively. No significant differences (P > 0.05) in reduction were observed between the Salm. Enteritidis cocktail and Salm. Enteritidis PT 30 inoculum. Reduction of Salm. Enteritidis increased as a function of treatment time, with 25 s being sufficient to achieve a 5-log reduction. Discolouration and visible formation of wrinkles were observed following steam pasteurization of more than 35 s.


CONCLUSIONS
Steam pasteurization of 25 s is sufficient to achieve a 5-log reduction of Salm. Enteritidis inoculated on raw almonds without visual quality degradation.


CONCLUSIONS
Steam pasteurization is an effective alternative to reduce or prevent Salm. Enteritidis contamination on raw almonds.
Chang
S-S
SS
School of Food Science, Washington State University, Pullman, WA 99164-6376, USA.
Han
A R
AR
Reyes-De-Corcuera
J I
JI
Powers
J R
JR
Kang
D-H
DH
D001434:Bacteriophage Typing; D005506:Food Contamination / Q000517:prevention & control; D005511:Food Handling / Q000379:methods*; D005516:Food Microbiology; D027861:Prunus / Q000382:microbiology; D012477:Salmonella enteritidis / Q000254:growth & development*; D013227:Steam
D013227:Steam