Optimization and spray-drying of nisin-enriched fermentation broth for antimicrobial powder production

Abstract

NCIMB 86100 reached 9,120 IU/mL at 100 g/L DW, 50 g/L SM, and 50 g/L GS. Spray-drying with different maltodextrin and DW levels was then tested to maximize nisin adsorption. The most effective formulation, using 5% maltodextrin, yielded an antimicrobial powder with an activity of 41,000.50 IU/g, representing approximately a 4.5-fold enhancement compared to the optimized fermentation broth. These results show that active nisin can be incorporated into antimicrobial powders through direct fermentation and spray-drying, offering a scalable, economical clean-label approach for food preservation.