Vacuum steam treatment of soft wheat: Quality and reduction ofEscherichia coliO121 andSalmonellaEnteritidis PT30

Background and objectives Several foodborne outbreaks due to contaminated wheat flour have occurred, resulting in a need for a microbial reduction process. Thermal treatments utilizing high temperatures can compromise wheat end-use quality. Vacuum steam treatment (VST) is a promising method for reducing pathogens on wheat. This study determined the pathogen inactivation levels on soft red winter (SRW) wheat while maintaining flour functionality. Findings Soft red winter wheat samples underwent VST for 4 and 8 min at 65, 75, and 85 degrees C prior to milling. SRW flour was evaluated for end-product quality. Increasing VST temperatures negatively impacted bread quality due to protein denaturation. Cake and cookie quality parameters resulted in little to no significant (p < .05) difference with increasing VST temperatures. SRW wheat was also inoculated withEscherichia coliO121 andSalmonellaEnteritidis PT30. The treatments resulted in a maximum average microbial reduction of 5.09 +/- 0.50 log CFU/g forSalmonellaand 7.34 +/- 0.11 log CFU/g forE. coli. Conclusions Vacuum steam treatment could be used by the milling industry to effectively inactive pathogens without compromising soft wheat flour quality. Significance and novelty Vacuum steam treatment process could improve the safety of wheat flour-based products without adding chemical treatments and while maintaining flour quality.