What makes starch from potato (Solanum tuberosum L.) tubers unique: A review.

The use of starch in food systems in many instances relies on its thickening and gelling capacity. When native starches fail to match process and/or product-specific requirements, starches are physically and/or chemically modified to meet end-use demands. Evidently, differences between starches of varying botanical origin have to be considered when selecting or modifying starches for particular applications.

Reaction pattern differences impact physical properties of starches derivatized to the same extent in a model cross-linking system.

This study investigated the physical properties of maize (MS) and wheat (WS) starches derivatized with 5-(4,6-dichlorotriazinyl)aminofluorescein (model cross-linking system) to have the same overall fluorescence intensity on starch molecules, but reacted either more uniformly throughout granules (UD) or more at granule surfaces (SD). Both MS and WS derivatives had lower swelling powers (SP) at 90°C than their respective native starches. The UD derivatives had lower SP (90°C) and greater retrogradation enthalpies than did SD derivatives, consistent with their lower peak and higher setback pasting viscosities.

Methodologies for producing amylose: A review.

Three main in vitro approaches can be distinguished for obtaining amylose (AM): enzymatic synthesis, AM leaching, and AM complexation following starch dispersion. The first uses α-d-glucose-1-phosphate (G1P), a glucosyl primer with a degree of polymerization (DP) of at least 4 and phosphorylase (EC 2.4.

Systemic availability and metabolism of colonic-derived short-chain fatty acids in healthy subjects: a stable isotope study.

Key Points: The short-chain fatty acids (SCFAs) are bacterial metabolites produced during the colonic fermentation of undigested carbohydrates, such as dietary fibre and prebiotics, and can mediate the interaction between the diet, the microbiota and the host. We quantified the fraction of colonic administered SCFAs that could be recovered in the systemic circulation, the fraction that was excreted via the breath and urine, and the fraction that was used as a precursor for glucose, cholesterol and fatty acids. This information is essential for understanding the molecular mechanisms by which SCFAs beneficially affect physiological functions such as glucose and lipid metabolism and immune function.

Element distribution and iron speciation in mature wheat grains (Triticum aestivum L.) using synchrotron X-ray fluorescence microscopy mapping and X-ray absorption near-edge structure (XANES) imaging.

Several studies have suggested that the majority of iron (Fe) and zinc (Zn) in wheat grains are associated with phytate, but a nuanced approach to unravel important tissue-level variation in element speciation within the grain is lacking. Here, we present spatially resolved Fe-speciation data obtained directly from different grain tissues using the newly developed synchrotron-based technique of X-ray absorption near-edge spectroscopy imaging, coupling this with high-definition μ-X-ray fluorescence microscopy to map the co-localization of essential elements. In the aleurone, phosphorus (P) is co-localized with Fe and Zn, and X-ray absorption near-edge structure imaging confirmed that Fe is chelated by phytate in this tissue layer.

Quantification of in Vivo Colonic Short Chain Fatty Acid Production from Inulin.

Short chain fatty acids (SCFA), including acetate, propionate, and butyrate, are produced during bacterial fermentation of undigested carbohydrates in the human colon. In this study, we applied a stable-isotope dilution method to quantify the in vivo colonic production of SCFA in healthy humans after consumption of inulin. Twelve healthy subjects performed a test day during which a primed continuous intravenous infusion with [1-(13)C]acetate, [1-(13)C]propionate and [1-(13)C]butyrate (12, 1.

Preparation of cross-linked maize (Zea mays L.) starch in different reaction media.

Granular normal maize starch was reacted with sodium trimetaphosphate in deionized water ( [Formula: see text] ), aqueous sodium sulfate solution ( [Formula: see text] ), aqueous ethanol (MSethanol) or aqueous acetone (MSacetone) under otherwise identical reaction conditions. Analysis of the resultant starches by Rapid Visco Analysis (RVA) showed that the starch was cross-linked to a higher degree in aqueous ethanol or aqueous acetone than in water or sodium sulfate solution, and with minimal starch leaching. While MSacetone and MSethanol had incorporated similar levels of phosphorous, RVA analysis and microscopic analysis showed that MSacetone granules were more effectively stabilized by cross-linking than MSethanol granules.

Distribution of Minerals in Wheat Grains (Triticum aestivum L.) and in Roller Milling Fractions Affected by Pearling.

The distribution of minerals in (pearled) wheat grains was measured by synchrotron X-ray fluorescence, and the impact of pearling (0, 3, 6, 9, and 12% by weight) on the mineral composition of flour, shorts, and bran was identified by ICP-MS. The xylem mobile elements (Mn, Si, Ca, and Sr) dominated in the outermost bran layers, while the phloem mobile elements (K, Mg, P, Fe, Zn, and Cu) were more concentrated in the aleurone. Pearling lowered the concentrations of xylem mobile elements and increased the concentrations of most phloem mobile elements in the pearled grains.

Moisture distribution during conventional or electrical resistance oven baking of bread dough and subsequent storage.

Electrical resistance oven (ERO) baking processes bread dough with little temperature gradient in the baking dough. Heating of the dough by means of an ERO is based on the principles of Joule's first law and Ohm's law. This study compared the changes in moisture distribution and physical changes in starch of breads conventionally baked or using an ERO.

Molecular and morphological aspects of annealing-induced stabilization of starch crystallites.

A unique series of potato (mutant) starches with highly different amylopectin/amylose (AP/AM) ratios was annealed in excess water at stepwise increasing temperatures to increase the starch melting (or gelatinization) temperatures in aqueous suspensions. Small-angle X-ray scattering (SAXS) experiments revealed that the lamellar starch crystals gain stability upon annealing via thickening for high-AM starch, whereas the crystal surface energy decreases for AM-free starch. In starches with intermediate AP/AM ratio, both mechanisms occur, but the surface energy reduction mechanism prevails.

Fate of starch in food processing: from raw materials to final food products.

Starch, an essential component of an equilibrated diet, is present in cereals such as common and durum wheat, maize, rice, and rye, in roots and tubers such as potato and cassava, and in legumes such as peas. During food processing, starch mainly undergoes nonchemical transformations. Here, we focus on the occurrence of starch in food raw materials, its composition and properties, and its transformations from raw material to final products.

Presence of amylose crystallites in parboiled rice.

Mildly, intermediately, and severely parboiled Jacinto [16% free amylose (FAM) content] and Puntal (26% FAM content) rice samples were submitted to differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXD). DSC thermograms revealed ungelatinized starch only in mildly parboiled rices and retrograded amylopectin in all parboiled samples. Amylose crystallites were present in intermediately and severely parboiled samples but could not be detected due to their high melting temperature.