Influence of Acidity in Paste Properties of Modified Corn Starch Through Natural Fermentation

Abstract

The objective of this research was to carry out the fermentation of corn starch in the same manner as cassava starch fermentation and to study its behavior during the fermentation process, analysing acidity and paste properties. CoS (corn starch) and CaS (cassava starch) were used. The sample was analysed by paste properties and acidity, at time 0, at every 7 days until the end of fermentation and after sun-drying. Regarding viscosity peak, CaS samples showed higher values, in the resistance attribute when comparing CoS and CaS samples those that had the same fermentation time did not present significant difference between them. CoS samples showed no significant difference between break results, but they did differ when compared to CaS samples. Only NCaS (native cassava starch) had greater retrogradation compared to CoS samples. However, the initial samples NCoS (native corn starch) and NCaS did not present differences in final viscosity results. However, they presented the highest values for this parameter with results of 171.50 and 180.50 RVU (Rapid Visco Units), respectively. Correlating results of acidity with paste properties it was observed that with fermentation time and consequent acidity increase, paste properties had important changes, decreasing the values of the measured parameters, only the paste temperature remained constant. It is concluded that the natural fermentation modification of corn starch compared with cassava starch had similarities about acidity. However, for pasting properties were no significant differences and should be better clarified through functional analysis and application product. Keywords: Modified Starch; production; structure; paste properties.