The effect of ball-milling time of maize starch in either a ceramic or stainless steel pot on CWS is shown in Fig. 1. Results showed that the longer the milling time, the greater the CWS. Interestingly, the CWS of maize starch increased quickly through the first 3 h of milling but then slowed thereafter. This result is likely due to the fact that the ball becomes ensconced by the maize starch as the ball-milling time increases thus decreasing the crushing power Selleck Staurosporine of the ball as time increases. The observed increase in CWS of maize starch results in a greater viscosity, a smoother texture, and increases the processing tolerance as compared

to the traditional pregelatinized maize starch. The types of pot used in the milling process did not significantly affect CWS. However, following this website 5 h of ball-milling CWS increased quite dramatically in the ceramic pot (72.6%) and in the stainless steel pot (70.7%), as compared to the untreated maize starches (2.9%) (p < 0.05). This observed increase in CWS of the maize starch as the milling time increased is consistent with previous models showing that mechanical agitation is capable of degrading the crystalline regions of the starch thus allowing a greater entry of

water into the interior of the starch granule. The low CWS of untreated maize starch can be attributed to it having a more rigid structure and greater amylose Aldol condensation content [5] and [10]. We next investigated the X-ray diffraction spectra of maize starch

milled in ceramic and stainless steel pots with various CWS (30%, 45%, 60%, and 75%) (Fig. 2). The spectrum of the untreated starch sample shows two peaks at 18θ and 22θ, presumably reflecting the crystalline and amorphism regions in the starch. As the CWS of the starch increases the regions of amorphism become larger and larger at the expense of the crystalline regions, causing the diffraction pattern to decrease. This result shows that maize starch treated by ball-milling has been converted largely into a non-crystalline state. Consequently, the diffraction spectrum shows a broad, featureless peak typical of amorphism, indicating that during the ball-milling treatment the crystalline molecular structure of maize starch is destroyed and converted largely into a non-crystalline (amorphous) state. Of importance to this study, however, starch in a non-crystalline state has a higher CWS. Taken together, these results indicate that the ball-milling treatment of maize starch improves its physicochemical properties thus increasing its possible industrial applications because the market actually prefers starches with less extensive crystalline regions.