The influence of extrusion process on myo-inositol phosphate content and profile in snacks containing rye bran.

The analysis of phytates in extrudates containing rye bran was done by a colorimetric method with the Wade reagent. The changes in profiles of myo-inositol phosphates indicate that, although no isomers with positive physiological functions (such as I(1,4,5)P3, I(1,2,3)P3 or I(1,3,4,5)P4) were formed, the beneficial impact of extrusion is the reduction of phytates, as compared to the raw material. The obtained snacks containing rye bran received acceptable to desirable sensory scores.

The model of the rheological behavior of gelatinized starch at low concentrations.

The optical density at the wavelength from 300 to 800 nm and the rheological behavior of gelatinized starch at its concentration from 3 to 30 g/L and the medium pH from 2 to 11 were investigated. The volume concentration of the swelling associates of macromolecules or their globules increases when pH of gelatinized starch rises. An influence of the volume concentration of gelatinized starch on the dependence of the shear stress on shear rate was studied. The dynamic viscosity is proportional to the volume concentration at the gelatinized starch concentration lower than 25% and proportional to the logarithm of the volume concentration at the starch concentration greater than 25%. Proposed mathematical model takes into account an influence of the volume concentration of swelling starch globules and the concentration of glucoside links of macromolecules between the globules of macromolecules or their associates on the dynamic viscosity of gelatinized starch. This model allows to describe the experimental data obtained.

Current research addressing starch acetylation.

Though modification of starch through acetylation is known for about 150years, it is still an object of extensive studies at various research centers worldwide. This manuscript presents an overview of literature from the last 5years concerning starch acetylation. It also describes the applied raw materials, production procedures of acetylated starch and correlations between the degree of substitution with acetyl groups and properties of the modified preparations.

Effect of the production method on the properties of RS3/RS4 type resistant starch. Part 1: properties of retrograded starch (RS3) produced under various conditions and its susceptibility to acetylation.

The objective of this study was to establish the effect of the concentration of a starch paste subjected to freezing on the properties of the produced retrograded starch, and to determine its susceptibility to acetylation with acetic acid anhydride. A starch paste (1, 4, 10, 18 or 30g/100g) was produced from native potato starch that was frozen, defrosted and dried. Al preparations of retrograded starch had the same chemical structure determined with the technique of nuclear magnetic resonance (NMR) and diversified physical form visible on photos taken with an electron microscope (SEM). An increase in the concentration of paste, used to produce the preparations, resulted in decreased: amylose content (from 25.0 to 20.4/100g), solubility in water (from 41.1 to 20.1/100g), swelling power (from 45.0 to 19.3/g), and susceptibility of the preparations to the action of amyloglucosidase (from 95.4 to 83.6/100g). The heat of phase transition of solubilisation determined with differential scanning calorimetry (DSC) ranged from 3.8 to 7.1J/g, and the initial temperature of transition was increasing from 43.4 to 49.7°C along with an increasing concentration of the paste subjected to retrogradation. The 1-10/100g concentration of the paste used to produce preparations was observed to increase, whereas that between 10 and 30/100g to decrease the susceptibility to acetylation and viscosity of the prepared pastes, determined both with a Brabender viscograph and a Haake oscillating-rotational viscosimeter.