Instant Cascara Beverages with Inulin-Type Carriers: Production Yield, In Vitro Biological Activity and Receptor-Level Responses

Background: Instant Cascara (IC) beverages, derived from dried coffee cherry pulp, represent an upcycled plant-based ingredient rich in phenolic compounds and methylxanthines. Although spray-drying enables the production of soluble cascara powders without carriers, previous sensory evaluation highlighted limitations in palatability, supporting the need for formulation strategies. Objective: To evaluate how the incorporation of inulin-type carriers with different degrees of polymerization modulates production yield, the apparent recovery of bioactive compounds, and formulation-dependent in vitro biological and receptor-level responses of Instant Cascara beverages. Methods: Formulations without carrier (IC 0.0) and with long-chain inulin (IC 1.0) or oligofructose-enriched inulin (IC 2.0) were prepared and characterized. Production yield, phytochemical composition, and in vitro antioxidant, anti-inflammatory, antiproliferative, and receptor-mediated responses were assessed using analytical tools, cell-based assays, and receptor-based platforms. Results: Carrier incorporation improved production yield, particularly for IC 1.0. Although differences in apparent recovery of bioactive compounds were observed, all formulations preserved relevant in vitro biological activities. IC 2.0 showed stronger nitric oxide inhibition and apoptosis induction in colorectal cancer cell models. Receptor-based assays revealed formulation-dependent differences, including reduced activation of bitter taste receptors (TAS2Rs), absence of sweet receptor (TAS1R2/TAS1R3) activation, and modulation of muscarinic (M3) and dopaminergic (D3/D4) receptor responses. These effects are consistent with variations in the composition and effective concentration of bioactive compounds between formulations, particularly caffeine. Conclusions: The incorporation of inulin-type carriers influences production yield and modulates in vitro biological responses and receptor-level responses of Instant Cascara beverages. IC 2.0 represents a formulation with a favorable balance between technological performance and functional responses, associated with a distinct receptor-level profile. This balance may be related to a reduced contribution of bitterness-associated compounds, such as caffeine, together with the preservation of other bioactive components contributing to the observed biological responses. These findings provide a mechanistic in vitro basis for future sensory and in vivo studies evaluating how formulation-dependent differences in bioactive composition may influence physiological responses and consumer perception.