Impact of drying technique on umbu-cajá pulp with the addition of probiotic culture: Optimization, cell viability, physicochemical, and functional properties

Abstract

This study aimed to assess the effects of spouted bed (SB) drying and freeze-drying (FD) on the properties of probiotic umbu-cajá pulp. The strain Bifidobacterium animalis ssp. lactis was employed to obtain this pulp. Initially, the study was conducted with two separate experimental designs, one for SB and another for FD, encompassing variables such as inlet temperature and concentrations of drying adjuvants (maltodextrin and inulin). This approach aimed to identify the most favorable conditions in terms of yield and cell viability. Both drying methods proved effective in preserving probiotic cells, with comparable viable cell counts (12 Log CFU g⁻¹) and process yield of up to 30.68%. Additionally, FD exhibited advantages in preserving and increasing levels of bioactive compounds, including phenolics and carotenoids, in the final product. In contrast, SB drying stood out for retaining carotenoids and exhibiting lower degradation of ascorbic acid. In summary, this study demonstrated that both SB drying and FD are promising approaches in producing powders from probiotic umbu-cajá pulp. However, the selection between the methods should be guided by specific production goals, considering the desired characteristics of the final product.