Effect of low‐temperature plasma treatment on the microbial inactivation and physicochemical properties of the oat grain

Abstract

AbstractBackground and ObjectivesNaked oat grain is easily contaminated by microorganisms, and it needs pretreatment to extend its shelf life. Low‐temperature plasma treatment (LTPT) has the advantages of less energy consumption, safety, and convenience, and its applications in grain include microbial inactivation and flour modification. Therefore, we studied the changes in oat microbes and the physicochemical properties of oats at different plasma treatment times (0, 5, 10, 15, and 20 min at an output discharge voltage of 60 kV).FindingsThe results demonstrated that LTPT significantly decreased the number of microorganisms with the increase in treatment time, especially at 20 min. LTPT increased the L* and b* values and decreased the a* value of oat flour. Proper treatment time (5–10 min) did not affect the germination rate of the grain. Compared to the control sample, LTPT increased the water‐binding capacity and swelling power of flour and decreased the peak viscosity, final viscosity, and setback value. However, LTPT did not change the crystal structure. Besides, by fitting the peak of the amide region in Fourier transfer infrared analysis, it was found that the β‐sheet and α‐helix increased after treatment for 5–10 min.ConclusionsThese results indicated that LTPT (20 min) can effectively reduce the microbial count of oats and proper time treatment (5–10 min) can regulate the function of the flour and improve its quality.Significance and NoveltyLTPT as a new nonheat treatment technology can not only effectively reduce the microbial content of the grain but also improve the quality of the flour, which is a better pretreatment method for oat flour.