Structural and Physicochemical Properties of Common Buckwheat Starch in Response to Different Fertilization Levels

Buckwheat is a typical medicinal and edible crop with high nutritional value, and the application of appropriate fertilizer can improve the quality of buckwheat starch. The changes of internal structure and physicochemical characteristics of common buckwheat grain starch under low, medium, and high fertilization levels are investigated. With increasing fertilizer amount, the volume proportion is increased, while the granule size distribution is reduced significantly. All of the common buckwheat starch samples show a typical A-type pattern in X-ray diffraction detection. Furthermore, with the increase of fertilization level, the amylose content, retrogradation, and the ratio of 1045/1022 cm-1 reduce and then raise, but the relative crystallinity, the ratio of 1022/995 cm-1, light transmittance, solubility, and swelling power increase and then decrease. In comparison to other fertilization levels, common buckwheat starch at the medium level has greater pasting temperatures and gelatinization enthalpy but lower pasting viscosities. These results indicate the medium fertilization level of 180 (N), 115.2 (P), and 84.6 (K) kg h-1 m-2 is more suitable for buckwheat starch quality, which can give information for buckwheat cultivation. In this study, the changes of internal structure and physicochemical characteristics of common buckwheat grain starch under low, medium, and high fertilization levels are investigated, and the study finds that common buckwheat starch has desirable physicochemical properties under the medium fertilization level of 180 (N), 115.2 (P), and 84.6 (K) kg h-1 m-2. image