Abstract:
Macrobrachium rosenbergii was rich in nutritional components and has delicious flavor, which had remarkable commercial value. However, it is prone to spoilage and deterioration due to high moisture content. Drying is an important way for the high-value processing and utilization of aquatic products. In this study, the effects of initial status of
M. rosenbergii meat (both the fresh
M. rosenbergii meat and the frozen
M. rosenbergii meat), microwave power intensities (1~5 W/g), and drying temperatures (45~60 ℃) on the drying efficiency, specific energy consumption, microstructure, and quality attributes of
M. rosenbergii meat to obtain dried shrimp products with superior quality and high energy efficiency during microwave vacuum drying (MVD). The optimal drying conditions were selected based on a comprehensive weighted scoring method by a comprehensive assessment of the drying efficiency and quality attributes of dried products. The results demonstrated that compared to fresh
M. rosenbergii meat, frozen samples that directly treated by MVD resulted in the dried products possessing a more intact structure with more internal pores and stable protein structure, as well as a higher astaxanthin content (0.93 μg/g), improved color, superior rehydration capacity, enhanced water-holding ability, and a significantly higher comprehensive quality score (
P<0.05). At microwave power intensity of 5 W/g, microwave vacuum dried
M. rosenbergii meat exhibited a denser porous structure, accompanied by the shortest drying time (15.27 min), lowest specific energy consumption (4.55 kW∙h/kg), highest water-holding capacity (20.34%), and highest comprehensive score among the tested power intensity levels (
P<0.05). Among the four controlled temperatures,
M. rosenbergii meat dried at 55 ℃ displayed regular internal pores and moderate fiber contraction, along with a lower hardness (200.57 N), and superior rehydration ratio (5.31) and water-holding capacity (20.42%). To sum up, compared to the fresh
M. rosenbergii meat, the frozen meat was suitable material during MVD. The frozen
M. rosenbergii meat was recommended to be dried at a power intensity of 5 W/g and drying temperature of 55℃ to achieve the dried products with superior quality, high drying efficiency and lower energy consumption.