Influences of Carrier Agents on Microbial Viability and Physicochemical Properties of Spray-Dried Coconut Yogurt

Abstract

Plant-based fermented coconut yogurt, valued for its functional properties, requires transformation into a shelf-stable powder, necessitating carriers to overcome particle stickiness and preserve probiotic viability. The objective of this study was to investigate the influence of polysaccharide carriers (maltodextrins DE 2, 10, and 19, and resistant dextrin) on processing efficiency, physicochemical stability, and lactic acid bacteria (LAB) viability. The feed, standardized to 15% total solids (initial LAB counts of 8.54 log CFU/g), was spray-dried at a 120 °C inlet temperature and a 65 °C outlet temperature. The drying condition reduced LAB viability by two log cycles regardless of the tested carriers. Maltodextrin DE 19 showed the highest powder yield, the lowest water activity, and a higher water solubility index. No significant differences in bulk density, pH, titratable acidity, and lactic acid content were observed among samples. Low-DE maltodextrins (DE 2 and 10) demonstrated significantly higher retention of sensitive malic and citric acids compared to DE 19. The current findings suggested that high-DE carriers provided beneficial effects on physical processing via kinetic shell formation, while low-DE carriers were able to protect against the loss of small organic acids. Overall, the study lays a foundation for spray-dried carrier development for coconut yogurt. © 2025 by the authors.