Effects of structural imperfection on gelatinization characteristics of amylopectin starches with A- and B-type crystallinity.

The aim of the present work was to investigate the effect of physical structures on the properties of starch granules. Starches with a high amylopectin content possessing A- and B-type crystallinity were chosen for the study. The gelatinization temperature decreased in the following order: maize (A) > potato (B) > wheat (A) > barley (A), which did not reflect a correlation with the type of crystallinity.

[Resistant starches. Part II. Physico-chemical and technological aspects solution medico-biological problems].

This paper is a review of the recent literature data related to structure, composition and physico-chemical properties of starches as well as the special methods of processing of the starch containing raw sources producing the food products with increasing content of resistant starches. The prognosis is made about usefulness of such resistant starches for control of some metabolic disorder in human organism and for prophylactic aims.

[Resistant starches. Part 1. General description and physiologic aspects].

This paper the recent data related to useful nutritional properties of resistant starches which combine the functional features of food fibers and prebiotics. The low glycaemic index of resistant starches, as well as their specific way of metabolism in gastrointestinal tract resulting in production of short-chain fatty acids in large intestine is discussed. The potential medicinal and prophylactic benefits of resistant starches to some disasters are described.

Structural parameters of amylopectin clusters and semi-crystalline growth rings in wheat starches with different amylose content.

Small-angle X-ray scattering (SAXS) and scanning electron microscopy (SEM) were used to investigate the internal structure of wheat starch granules with different amylose content. Different approaches were used for treatment (interpretation) of SAXS data to assess the values of structural parameters of amylopectin clusters and the size of crystalline and amorphous lamella in different wheat starches. The average values of the semi-crystalline growth rings thickness in starches have been determined and the relationship between structural characteristics and thermodynamic melting parameters is discussed.

Effects of annealing on the polymorphic structure of starches from sweet potatoes (Ayamurasaki and Sunnyred cultivars) grown at various soil temperatures.

Starches extracted from the sweet potato cultivars Sunnyred and Ayamurasaki grown at 15 or 33 degrees C (soil temperature) were annealed in excess water (3 mg starch/mL water) for different times (1, 4, 8 or 10h) at the temperatures 2-3 degrees K below the onset melting temperature. The structures of annealed starches, as well as their gelatinisation (melting) properties, were studied using high-sensitivity differential scanning calorimetry (HSDSC). In excess water, the single endothermic peak shifted to higher temperatures, while the melting (gelatinisation) enthalpy changed only very slightly, if any.