Novel Strategy for Manufacturing Convenient Dehydrated Dumplings: Relying on Microwave Freeze-Drying and Its Underlying Mechanism

ABSTRACT

Microwave freeze-drying (MFD) has emerged as an efficient alternative in the dehydration process; therefore, the current work attempts to introduce MFD into the production of instant dumplings. Pork-filled dumplings were treated with MFD at varying microwave power densities (0.10, 0.25, and 0.40 W/g) and compared to traditional freeze-drying (FD). The disparities in drying time, rehydration ratio, hardness, microstructure, hierarchical structure, and gelatinization characteristics were examined. The results demonstrated that MFD0.25 reduced drying time by 82.69% compared to FD. As the microwave power density increased from 0.10 to 0.40 W/g, the rehydration ratio increased from 1.55 to 1.83, then decreased to 1.51, and the rehydrated dumpling wrappers’ hardness decreased from 113.90 to 80.07 gf before increasing to 95.39 gf. The starch's relative crystallinity reduced from 16.87% to 7.35% and then rose to 9.01%, lower than FD's 18.59%. Further analysis revealed that MFD mitigated the adsorption of dumpling wrappers to the oil/water mixture, and the formation of starch–lipid complexes played a crucial role in determining the quality of dehydrated dumplings.

Practical Application

Dumplings are a staple food in many cultures, particularly in China, where they are enjoyed both as a traditional dish and a convenient meal. However, dumplings contain 60%–70% moisture and require drying to extend their shelf life. Microwave freeze-drying (MFD) technology offers an efficient solution for dumpling production, addressing the challenges of preserving freshness and extending shelf life. Compared to traditional methods, MFD enhances drying efficiency, ensures uniform moisture removal, and reduces quality loss. This technology allows for precise control over drying parameters, improving product consistency and competitiveness in the growing ready-to-eat food market. Furthermore, MFD supports sustainability goals by reducing energy consumption and operational costs, positioning it as a key innovation for the future of food processing.