Properties of Oxidized Potato Starch–Potassium Alum Mixtures, and Their Application in Starch Noodles

This study explores the effects of potassium alum (PA) on oxidized potato starch (OS) with a carboxyl content of 0.0186%, in terms of their pasting and rheological properties. Furthermore, the application of oxidized starch in the manufacturing of starch noodles is investigated. The results indicate a positive correlation between pasting temperature and PA content (65.6–67.7 °C), while showing a negative correlation with peak viscosity (409–236 BU). The addition of PA leads to reduced dynamic moduli ( G ′' and G ″), consistency coefficient ( K ), and hysteresis area, accompanied by an elevated fluid behavior index ( n ). Shear recovery assays demonstrate a positive correlation between PA content and shear resistance, with recovery rates escalating from 76% to 84%. The mouthfeel of starch noodles produced using oxidized starch exhibit comparable to commercial counterparts (PA content 0.35%), but with lower PA levels (at 0.2%). Additionally, these starch noodles have a higher whiteness compared to starch noodles made with potato starch.