Structural characterization and physicochemical properties of starch from four aquatic vegetable varieties in China

Nelumbo nucifera Gaertn., Eleocharis dulcis, Sagittaria sagittifolia L., and Trapa bispinosa Roxb. are common aquatic vegetables that are rich in starch. Starches from these four aquatic vegetables and their applications in edible films were studied to facilitate full use of starch resources. Significant differences in transparency, freeze-thaw stability, water solubility index, swelling power, water and oil absorption capacities, starch particle morphology, and rheology were observed among the starches from these four aquatic vegetables. All starches exhibited a typical "A" type diffraction pattern. N. nucifera, E. dulcis, and S. sagittifolia starches have similar thermal properties, while T. bispinosa starch has a higher gelatinization temperature. S. sagittifolia starch film has the highest transparency and lower WVP and water solubility. These results will promote the development of products based on starch obtained from aquatic vegetables.