Water plays a central role in agricultural production, food processing, and food matrices, influencing plant growth, nutrient transport, mass transfer, colloidal stability, and product quality. This study investigated whether water passed through an inline mineral-composite conditioning device (PCW) was associated with subtle physicochemical variations and responses in brewing and exploratory agricultural systems. Compared with untreated water, PCW showed subtle variations in hydrogen-bond-sensitive spectral regions, including an NIR O–H first-overtone shift (Δλ = 1.8 nm, p < 0.05), a slight downfield shift of the ¹ H NMR water resonance (Δδ ≈ 0.15 ppm), minor FTIR band shifts and broadening, and slightly higher measured density ( p = 0.027), dynamic viscosity ( p = 0.0020), and kinematic viscosity ( p = 0.0028), without detectable changes in chemical composition. In the exploratory agricultural evaluation, PCW was associated with a numerically higher mean radish yield than untreated water (47.12 vs. 27.50 t ha ⁻¹ ), whereas maize grain yield was similar (11.09 vs. 10.91 t ha ⁻¹ ). In the evaluated brewing batches, PCW was associated with significantly higher foam quality ( p = 0.02) and carbonation scores ( p = 0.03), together with significantly lower perceived cloudiness scores ( p < 0.01), while the remaining sensory attributes did not differ significantly. Overall, passage of water through the inline mineral-composite conditioning device was associated with subtle physicochemical variations and system-dependent responses. Accordingly, the findings should be interpreted as associative and system-dependent rather than as evidence of a defined molecular-scale mechanism, while the agricultural observations should be considered exploratory and hypothesis-generating rather than evidence of efficacy.