Enhancing Viability of <i>Lactobacillus plantarum</i> <scp>BG24</scp> Through Optimized Spray Drying: Insights Into Process Parameters, Carrier Agents, Comparative Analysis With Freeze Drying, and Storage Condition Influences

This study investigated the survival dynamics of <i>Lactobacillus plantarum</i> BG24, a probiotic strain, within reconstituted skim milk (RSM) and yeast extract (YE) matrices during the spray-drying (SD) process, encompassing of inlet/outlet air temperatures. Notably, optimum SD parameters were found to be an inlet air temperature of 150°C and outlet air temperature of 83°C, that achieving high viability (92.23%), and reducing both moisture content (MC) (3.57%) and water activity (<i>a</i> _w) (0.266). The use of soy protein isolate (SPI), gum Arabic (GA), RSM, maltodextrin (MD), sucrose (SUC), and lactose in binary mixtures or alone was investigated in terms of the best survival rate of probiotic bacteria, and RSM alone and RSM + GA and SPI alone were found to be the best drying carriers giving higher viability during SD. SD at optimum process temperatures and freeze drying (FD) were compared in the survival rate of probiotic bacteria in the carrier of RSM with YE, and FD samples showed a higher survival rate (97.69%) than SD samples. It was determined that the storage temperature (4°C and 20°C) had an impact on the glass transition temperature, MC, <i>a</i> _w, and cell viability. Increased storage temperature led to a greater decrease in cell viability, especially for SD probiotic powders. These findings furnish critical insights into the intricate interplay among process parameters, carrier agents, drying techniques, and storage conditions, thereby elucidating avenues for refining probiotic preservation strategies within the ambit of SD, and by extension, in the domains of food and pharmaceutical sciences.