Correlations of the Composition,Minerals, and RVA Pasting Properties of Various Potato Starches

Multiple linear regression equations were developed to correlate the granule size distribution, composition, and minerals content with the Rapid Visco Analyser (RVA) pasting properties of potato starches of different cultivars. From the experimental values and the values of the regression coefficients, it could be observed that a higher level of amylose resulted in a lower peak viscosity (PV) and breakdown (BD) and higher setback (SB) and peak viscosity temperature (PVT) in the potato starches. The reverse was observed when the phosphorus content was higher. Smaller granule size was associated with a decrease in the PVT, whereas larger granules demonstrated higher PV, BD, and SB values in the potato starches. A higher calcium content was associated with a decrease in PV and an increase in BD, SB, and PVT. On the other hand, higher potassium was associated with an increase in PV, BD, SB, and PVT. The sodium contents demonstrated a higher PV and SB, and the reverse was observed in the BD and PVT. It is difficult to conclude the precise role of magnesium ions to the RVA properties although as divalent cations, they may have similar effect as calcium. From the positive and negative values of the regression coefficients it was shown that the correlation is useful for determining more precise values of the RVA pasting properties using a multiple linear regression equation. The correlations were also useful for predicting the effects of the starch composition and minerals on the RVA pasting properties.