Impact of Maltodextrin–Inulin Blends on the Physicochemical, Functional, and Technological Properties of Freeze-Dried cape Gooseberry (Physalis peruviana L.) and Pineapple (Ananas comosus) Juices

The use of fruit that does not meet export standards and the waste of fresh produce pose a challenge for the food industry, given the economic losses. This study evaluated the effect of different proportions of maltodextrin (MD) and inulin (I) (0%–100%) as carrier agents on the physicochemical, thermal, functional, and technological characteristics of freeze-dried powders from cape gooseberry and pineapple juice. The formulations were characterized by physicochemical, thermal, and technological analyses. All treatments had a pH of ≤4, acidity of <2.5%, and water activity (a_w) of <0.35. Moisture increased with I content, reaching up to 6.90%. Color varied depending on the type of agent, with better results in treatments with a single carrier. The glass transition temperature (T_g) decreased as the proportion of I increased and was highest in the treatment with 100% MD. The sorption isotherms at 25°C were adequately fitted to the Guggenheim–Anderson–de Boer (GAB) model (R² > 0.93), with higher hygroscopicity observed in powders with higher I content. No significant differences (p = 0.142) were observed in total phenolic content (TPC) among treatments; however, formulations containing MD generally showed slightly higher TPC values. In contrast, antioxidant capacity (AC), measured by FRAP and DPPH assays, showed significant differences (p < 0.001), with the 100:0 and 80:20 MD:I formulations exhibiting the highest values. In addition, this treatment presented optimal fluidity and high solubility. Overall, the results indicate that the formulation with 100% MD yielded a powder with technological and functional properties suitable for its potential application in functional foods.