Importance of intense pulsed light device design on the reduction of indigenous microorganisms and enhancement of vitamin D₂ levels in shiitake mushroom (Lentinula edodes) pills

This study investigated the microbial reduction and vitamin D₂ content of shiitake mushroom pills when using a pilot-scale intense pulsed light (IPL) device with two interchangeable pipe shapes-straight and curved pipes. Samples (150 g) were treated with IPL using voltages of 2800, 3400, and 4000 V for 1–20 min. Maximum 0.54- and 0.77-log microbial reductions were achieved for the straight and curved pipes, respectively, with vitamin D₂ levels increasing to 14.86 and 16.79 μg/g, respectively. These differences were attributable to the use of the curved pipe, resulting in the sample being exposed to light emitted from the side lamps for a longer period and over a larger surface area. Statistically significant differences were not observed in the sample's surface temperature, color, or moisture content after IPL treatment at 4000 V. These findings demonstrate that IPL effectively reduced microorganisms and increased vitamin D₂ content in shiitake mushroom pills.