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The retrogradation behaviors of five damaged wheat starches (DS) after milling 0, 30, 60, 90, and 120 min with different water contents (33, 50, 60 %) were evaluated. Milling treatment increased DS content and developed an agglomeration of small particles. After 7 days of storage, the recrystallinity and long-range ordered structure of starch pastes were increased with the contents of DS and water. This process led to a lower setback viscosity and poor leaching of amylose. LF-NMR indicated a conversion from tightly bound water and free water to weakly bound water. During storage, DS12 with 60 % water content had the highest retrogradation tendency where the retrogradation enthalpy increased by 1.5 J/g and 2.2 J/g compared with DS0 with 60 % and DS12 with 33 % water content. DS with higher water content promoted the water mobility and made the starch molecular chains migrated conveniently. These changes facilitated the recrystallinity process during retrogradation period.

Deep-sea cage aquaculture (DSCA) is an important way to expand new space for marine aquaculture, promote the transformation and upgrade of the fishery industry, and optimize the structure of marine aquaculture. Using the panel data of DSCA in China’s coastal areas from 2013 to 2021, this study constructs the SBM–Malmquist model to measure the DSCA production efficiency and analyzes its total factor productivity. The results show that the overall DSCA production efficiency exhibited an increasing trend in spite of a sharp decline in 2019. The efficiency exhibited regional differences, being the strongest in the Bohai Sea region, followed by in the Yellow Sea, the South China Sea, and the East China Sea regions. The overall total factor productivity remained generally stable, although a large fluctuation occurred between 2019 and 2021. Both pure technological efficiency and scale efficiency promoted the total factor productivity in 2019–2021, while the efficiency of technological changes in societal aspects declined. This study shows that the DSCA production efficiency is significantly influenced by input factors such as labor and capital investment. In addition, natural disasters inhibit the improvement of the production efficiency to some extent.