Effect of citric acid esterification conditions on the properties of the obtained resistant starch

This study was aimed at comparing selected properties of starch citrate obtained from native or retrogrades of potato starch at various temperatures (100, 130 or 160 °C) and at various doses of reactant (10, 20 or 40 g per 100 g). Higher susceptibility to esterification was demonstrated for retrograded starch, whereas the degree of esterification of the produced esters varied considerably (1.4 to 10.0 g per 100 g preparation) and was increasing along with increasing roasting temperature and dose of citric acid. The process of pasting occurred only in the esters obtained at a temperature of 100  °C, which resulted in a significant decrease in swelling power and solubility in water of the citrates produced at higher temperatures. The resultant starch citrates were characterised by significant resistance to amylolysis (ranging from 22 to 100 g per 100 g). There was observed an increase in starch resistance along with the increase in the acid dose and roasting temperature. All analysed properties of starch citrates were not correlated with the degree of esterification, but appeared to depend on the roasting, which may point to a significant effect of this factor on the mechanism of starch cross‐linking with citric acid.     

Study on iron availability from prepared soybean sprouts using an iron-deficient rat model

During soya seeds germination in FeSO₄ solutions their phytoferritin content is multiplied. Prepared soybean sprouts have been proposed as a safe and easily available source of iron supplementation. The preparation was compared with FeSO₄ and ferritin isolates, using rats with induced iron deficiency anaemia. After the end of the 2-week supplementation experiment, it was observed that no statistically significant differences in haemoglobin concentration, mean corpuscular volume, mean corpuscular haemoglobin, and mean corpuscular haemoglobin concentration existed between those animals supplemented with sprouts enriched in ferritin, ferritin isolate and FeSO₄ and healthy animals forming the control group. Moreover, the examined preparation had a beneficial influence on the recreation of ferritin reserves in both the liver and the blood serum, and also did not induce negative alterations in general growth parameters of animals. Use of an easily obtainable ferritin iron source may be a profitable alternative in supplementation due to its wide availability and food preservative properties.     

Counterexamples to the Maximum Speed/Energy IMC Theory – A New Geometric Consideration Incorporates the Multivariable Perfect Control Defined in the LTI Discrete-Time State-Space Framework

Abstract

In this paper, the counterexamples to the general theory related to the state-feedback IMC plants are given and investigated. It is shown, that the maximum-speed multivariable perfect control schemes do not necessitate the maximum-energy of the control input variables. In that way, the IMC peculiarities involving the nonzero perfect control closed-loop poles are indicated, which constitutes a solid counterweight to the well-known general system theory. A new geometric approach results in counterexamples for both full and non-full rank plants, giving rise to the introduction of a complete analytical paradigm in the nearest future. Numerical examples confirm the intriguing issues covering the paper.