Recent outbreaks traced to contaminated flour have created a need in the milling industry for a process that reduces pathogens in wheat while maintaining its functional properties. Vacuum steam treatment is a promising technology for treatment of low moisture foods. Traditional thermal treatment methods can compromise wheat functionality due to high temperatures, thus maintaining the functional quality of the wheat protein was critical for this research. The objective of this study was to evaluate the effect of vacuum steam treatment on hard red spring (HRS) wheat kernels on final flour quality and overall efficacy of vacuum stream treatment to reduce pathogens on HRS wheat kernels. In the first part of the study, HRS wheat samples were treated with steam under vacuum at 65, 70, 75, and 85 °C for 4 and 8 min. Significant changes in dough and baked product functionality were observed for treatments ≥70 °C. For all of the quality tests performed, treatment time had no significant effect. After determining that vacuum steam treatment at 65 °C best preserved product quality, HRS wheat was inoculated with Escherichia coli O121 and Salmonella Enteritidis PT30, and processed at 65 °C for 0, 2, 4, 6, or 8 min periods. The treatments achieved a maximum average reduction of 3.57 ± 0.33 log CFU/g for E. coli O121 and 3.21 ± 0.27 log CFU/g for Salmonella. Vacuum steam treatment shows potential as an effective pathogen inactivation method for the flour milling industry.

This content is only available as a PDF.
You do not currently have access to this content.