In the quest to make food processing more energy-efficient, researchers have turned to innovative drying techniques that could revolutionize the industry. A recent study published in the journal Food Science and Technology (Shipin gongye ke-ji) explores a novel approach to drying Macrobrachium rosenbergii, commonly known as the giant freshwater prawn. The research, led by Xiaoning Cheng from the College of Agricultural Engineering and Food Science at Shandong University of Technology, combines vacuum freeze drying (VFD) with instant controlled pressure drop (DIC) to enhance drying efficiency while maintaining product quality.
The study addresses a critical challenge in the food industry: the high energy consumption associated with traditional drying methods. By integrating DIC with VFD, Cheng and his team aimed to reduce drying time and improve efficiency without compromising the quality of the dried prawn meat. “The combination of VFD and DIC offers a promising solution to the energy-intensive nature of conventional drying processes,” Cheng explained. “Our findings suggest that this method can significantly shorten drying time and enhance efficiency, making it a viable option for large-scale food processing.”
The researchers investigated the effects of different conversion point moisture contents (60%, 50%, 40%, and 30%) on the drying kinetics, microstructure, and quality characteristics of the dried prawn meat. They compared these results with those obtained from VFD alone. The study revealed that when the conversion point moisture content was 60%, the VFD-DIC method produced a severely damaged structure, significant volume shrinkage, and quality degradation compared to VFD alone. However, as the conversion point moisture content decreased, the quality of the dried prawn meat improved, approaching that of the VFD-alone products.
One of the most significant findings was that at a conversion point moisture content of 30%, the quality characteristics of the dried prawn meat were virtually indistinguishable from those obtained with VFD alone. “When the conversion point moisture content was 30%, the crude protein content, shrinkage rate, and texture properties of the prawn meat were not significantly different from those of the VFD-alone products,” Cheng noted. This discovery is crucial for the food industry, as it demonstrates that the VFD-DIC method can achieve high-quality results while being more energy-efficient.
The study also highlighted the importance of transverse relaxation time in assessing the quality characteristics of the dried prawn meat. Correlation and hierarchical cluster analyses showed that the quality of shrimp meat with a conversion point moisture content of 30% was comparable to that of the control group (VFD alone). This finding provides a strong theoretical basis for the practical application of the VFD-DIC method in the food industry.
The implications of this research are far-reaching. For the energy sector, the development of more efficient drying techniques could lead to significant energy savings and reduced carbon emissions. For the food industry, the ability to produce high-quality dried products more efficiently could enhance profitability and sustainability. As Cheng and his team continue to refine their methods, the potential for widespread adoption of the VFD-DIC technique grows, paving the way for a more energy-efficient and sustainable future in food processing.