Influence of atmospheric pressure plasma jet on the structure of microcrystalline starch with different relative crystallinity

Summary This study demonstrated the effect on microcrystalline starch ( MS ) with different relative crystallinity ( RC ) by atmospheric pressure plasma jet ( APPJ ) treatment for 1, 3, 5 or 7 min. The morphology of MS granules was destroyed according to Scanning electron microscopy ( SEM ) analysis. APPJ treatment did not change the crystalline type of MS , but obviously decreased the RC of MS . Short‐range molecular order of MS was clearly decreased after APPJ treatment though the Fourier transform infrared ( FTIR ) and Raman spectroscopy. Notably, the effect of APPJ on crystalline and short‐range order structure of MS was gradually increased with the increase of RC , which revealed that the crystalline region of MS might be destroyed by APPJ . Furthermore, the pH of MS was decreased while water binding capacity ( WBC ) and swelling volume ( SV ) of MS were increased. Therefore, the APPJ treatment could be used as an alternative physical technology for starch modification.