Effect of non-ionic surfactant and acidity on chitosan nanofibers with different molecular weights

in Carbohydrate Polymers (2011), 83(2), 470-476

Characterization of hemicellulosic fractions from spelt hull extracted by different methods

in Carbohydrate Polymers (2011), 85

Comparative study of the effect of drying temperatures and heat-moisture treatment on the physicochemical and functional properties of corn starch

in Carbohydrate Polymers (2010), 79(3), 633-641

This manuscript compares the modifications induced by the heat-moisture treatment of native starch (HMT) and by the hot-air drying of corn on wet-milled starch granules. High temperatures applied during ... [more ▼]

This manuscript compares the modifications induced by the heat-moisture treatment of native starch (HMT) and by the hot-air drying of corn on wet-milled starch granules. High temperatures applied during both corn drying and HMT reduced the swelling capacity of granules, increased the starch gelatinization temperatures and decreased their residual enthalpy. Pasting behaviour of pre-treated starch showed a decrease of peak and breakdown viscosity when corn drying and HMT temperatures increased. Microscopic analysis showed that after hydrothermal treatment, starch granules extracted from corn dried at lower temperature swell more significantly than those extracted from corn dried at higher temperature. All these changes suggest the occurring of structural modifications within starch granules during high-temperature pre-treatments. At similar temperatures and initial moisture contents, HMT affected the physicochemical and functional properties of cornstarch more dramatically than hot-air drying. Differences induced by these two treatments were attributed to the availability of water around granules during these two pre-treatment procedures. [less ▲]

Physicochemical and functional properties of starches from sorghum cultivated in the Sahara of Algeria

in Carbohydrate Polymers (2009), 78(3), 475-480

Pure starches were isolated from white and red sorghum cultivated in Tidikelt, a hyper and region situated in south Algeria. Amylose content, X-ray pattern and theological properties of starches were ... [more ▼]

Pure starches were isolated from white and red sorghum cultivated in Tidikelt, a hyper and region situated in south Algeria. Amylose content, X-ray pattern and theological properties of starches were examined. The amylose content in white sorghum starch (27.1%) was slightly higher than that in red sorghum (24.8%). The swelling power and the solubility behavior of both starches were nearly similar below 65 degrees C. At higher temperatures, starch isolated from the white sorghum cultivar showed higher swelling power and lower solubility index than pigmented sorghum starch. The pasting properties of starches determined by RVA, Rapid Visco Analyser showed different viscosity peaks. Red sorghum starch had a higher value (4731 cP) than white sorghum starch (4093 cP). For both sorghum, X-ray diffractograms exhibit an A-type diffraction pattern, typical of cereal starches and the relative degrees of crystallinity were estimated at 22.72% and 28.91%, respectively, for local white and red sorghum starch. DSC analysis revealed that sorghum starches present higher temperatures at the peak (70.60 and 72.28 degrees C for white and red sorghum starches, respectively) and lower gelatinization enthalpies (9.087 and 8.270 J/g for white and red sorghum starches, respectively) than other cereal starches. The results showed that physicochemical and functional properties of sorghum cultivar starches were influenced by the genotype and the environment. (C) 2009 Elsevier Ltd. All rights reserved. [less ▲]

Influence of drying temperature on functional properties of wet-milled starch granules

in Carbohydrate Polymers (2009), 75

Relationships between swelling capacities, pasting properties, rotational flow behaviour and textural properties of hydro-thermally heated wet-milled starch granules from corn dried between 60 and 130°C ... [more ▼]

Relationships between swelling capacities, pasting properties, rotational flow behaviour and textural properties of hydro-thermally heated wet-milled starch granules from corn dried between 60 and 130°C were investigated. High-drying temperatures applied during the corn drying process conferred to the wet-milled starch granules (WSG) such a rigidity which reduced their swelling capacities, their water binding capacities and their water solubility index after gelatinization. These granules changes affected their pasting characteristics, their flow behaviour and several textural parameters of gel formed from the wet-milled starch granule after gelatinization. The rigidity of granules was a major factor determining the formation of either starch pastes or gels. [less ▲]

Variations In Physicochemical And Functional Properties Of Starches Extracted From European Soft Wheat (Triticum Aestivum L.): The Importance To Preserve The Varietal Identity

in Carbohydrate Polymers (2008), 71(1), 32-41

The quality valuation of wheat is based on characteristics like yield, specific weight, protein content and protein quality. Until now. the starch properties are rarely considered as a quality criterion ... [more ▼]

The quality valuation of wheat is based on characteristics like yield, specific weight, protein content and protein quality. Until now. the starch properties are rarely considered as a quality criterion. In this study, we showed the influence of wheat cultivars (Triticum aestivum L.) and culture year on the intrinsic properties of starch, extracted from European wheat grown in the same conditions. For example, starch damage varied from 13.2 to 19.9 CDU in function of the cultivars and contribution of the B-type starch granules (<10 mu m) to the total volume ranged from 11.6% to 29.9%. Starch viscosity at 95 degrees C, characterized with alpha-amylase inactivation by 2 mM AgNO3 addition. varied from 276.5 to 351.5 BU with the wheat cultivars. It is apparent from this study that starch properties were principally influenced by the wheat cultivar and slightly by the culture year. A good relationship between the pasting properties of whole flour and starch were finally established, showing the important role of starch in the whole flour viscosity. A thorough working knowledge of starch properties could lead to an appropriate selection of wheat cultivar, well-adapted to industrial end uses, without encountering processing or end-products quality problems and with most cost-competitive production. [less ▲]

Determination of physical changes of inulin related to sorption isotherms: An X-ray diffraction, modulated differential scanning calorimetry and environmental scanning electron microscopy study

in Carbohydrate Polymers (2006), 63(2), 210-217

This paper gives a relationship between powdered inulin behaviour and physical parameters determination. Glass transition temperature (T,) and development of crystallinity were measured in relation to the ... [more ▼]

This paper gives a relationship between powdered inulin behaviour and physical parameters determination. Glass transition temperature (T,) and development of crystallinity were measured in relation to the water moisture of the polymer. These parameters were obtained by Modulated Differential Scanning Calorimetry (MDSC) and powder X-ray diffraction, respectively. In order to change the water content of the powder, adsorption and desorption isotherms (using different relative humidity storage conditions) were done and successfully fitted to the Guggenheim-Anderson-de Boer (GAB) model. Dependent on the relative humidity storage, a caking phenomenon occurred when glass transition temperature was under storage temperature. An Environmental Scanning Electron Microscopy (ESEM) study showed a structural change when water activity increased above 0.56 at 20 degrees C. A correlation between the increase of the crystallinity and the hardening of the powder was determined. ESEM permitted an observation of the development of some crystal structures among the amorphous system, confirmed by an increase of the diffraction peaks obtained by powder X-ray diffraction. These observations lead to an understanding of the physical characteristics of inulin related to the water moisture. (c) 2005 Elsevier Ltd. All rights reserved. [less ▲]