Flash vacuum expansion technology for small-scale production of fruit puree: Development and quality assessment

Fruit processing at small scale often lacks access to efficient, integrated technologies capable of ensuring product quality and safety. Flash Vacuum Expansion emerges as a promising alternative to conventional thermal treatments by coupling rapid steam heating with instant decompression, enabling simultaneous pasteurization and cooling, tissue disintegration, and deaeration. This study presents the design, construction, and validation of an optimized Flash Vacuum Expansion prototype tailored for small- and medium-scale agroindustries. The system integrates six unit operations—blanching, pasteurization, mashing, cooling, deaeration, and pulping—of which the last four are conducted under vacuum conditions. Heating is achieved through a screw conveyor blancher equipped with direct steam injection, while the vacuum operations are synchronized using double-valve airlocks. Performance was assessed using açai and Andean blackberry, evaluating microbial inactivation, physicochemical and rheological properties, and energy efficiency. FVE-treated purees showed complete microbial inactivation (<10 CFU/g), significant increases in pulp yield and extraction efficiency, reduced insoluble solids, enhanced pigment release, and superior rheological consistency. Energy consumption analysis revealed specific energy consumption (SEC) values as low as 0.97 MJ/kg—markedly lower than conventional processing benchmarks. The proposed FVE system represents a scalable and energy-efficient solution for producing high-quality fruit purees.