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Potatoes, especially colored, are perceived as a valuable source of bioactive compounds, and they are also an important raw material for starch production. There is virtually no information about starch from colored potatoes grown in Central Europe. Therefore, starches from light and colored potato varieties are isolated, and their particle size distributions, molecular masses, phosphorus content, gelatinization properties, water binding capacity, and solubility are analyzed. It is found that the mean and minimum granule size is similar for all investigated varieties, but colored varieties have larger granules. Moreover, starches isolated from colored potatoes are characterized by a higher phosphorus content than those isolated from light ones. It is shown that the solubility and water‐binding capacity of starch from colored potatoes is greater than that of light flesh, especially at higher temperatures. Starches from light flesh potatoes are characterized by significantly higher gelatinization enthalpy values than those from colored potatoes. [ABSTRACT FROM AUTHOR]

Bread staling could be diminished by the use of certain additives, including starch degradation products. The aim of the study was to check the influence of potato starch extrudates (which were produced at different extrusion temperatures - 90, 130 and 170°C) on the physical properties of wheat dough and bread, as well as the staling process of bread. In baking studies, ground starch extrudates were used to replace wheat flour at a substitution level of 5%. It was found that the extrudate prepared at 130°C had the most significant effect on the rheological properties of the dough. Bread with starch extrudates exhibited a lower volume and height when compared to the control. Starch extrudates did not influence the crust colour, but did have an impact on the crumb colour. The addition of starch extrudates to wheat bread had a detrimental influence on its hardness as it increased this particular parameter, despite the slower rate of starch retrogradation. The results confirm that bread staling is a complex process which could be affected by various factors, and not merely by starch retrogradation. [ABSTRACT FROM AUTHOR]

The aim of the research was to compare several physico-chemical parameters of potato starch modified using oxidation, extrusion, and combination of both, including content of amylose and non-polysaccharide components, amount of carboxyl groups, molecular mass distribution of polymers, pasting ability, and rheological properties. It was observed that oxidation, extrusion, and combined oxidation/extrusion of starch resulted in an increase of ash in potato starch, and the oxidized starch contained the lowest amount of non-carbohydrate compounds. Oxidation resulted in a decrease of phosphorus, while its content after extrusion increased. It was found that the level of apparent amylose dropped after all applied types of modification. Water binding capacity and solubility of oxidized starch differed slightly from the values measured for native starch, while a huge change in these characteristics was caused by extrusion. The highest change of molecular mass was observed after combined modification and the lowest in case of extruded starch. Modification of starch affected its rheological properties, which exhibited low viscosity and was more susceptible to shearing forces. [ABSTRACT FROM AUTHOR]