Browsing by Author "Parada, Javier"

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    Effect of guar gum content on some physical and nutritional properties of extruded products
    (ELSEVIER SCI LTD, 2011) Parada, Javier; Miguel Aguilera, Jose; Brennan, Charles
    The effect of guar gum (0-10%) added to flour (maize, potato, rice, and wheat) prior to extrusion on the microstructure, physical properties (texture, expansion, density, pasting) and nutritional properties (starch digestibility) was investigated. The inclusion of guar gum did not decrease starch digestibility; rather, at 10% guar gum rapidly digestible starch increased by 24%, 15%, 25% and 43%, in maize, potato, rice and wheat flour-based products, respectively. In general, increases in starch digestibility appear to be related to the weaker microstructure (i.e., lower textural hardness), larger matrix surface area, and lower viscosity (pasting properties) of extrudates containing guar gum. These results suggest that microstructural changes affect the starch digestibility of extrudates; nevertheless, probably other factors such as particle size during digestion may also play an important role. (C) 2010 Elsevier Ltd. All rights reserved.
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    Effect of native crystalline structure of isolated potato starch on gelatinization behavior and consequently on glycemic response
    (ELSEVIER, 2012) Parada, Javier; Aguilera, Jose M.
    Effect of crystalline structure of two isolated potato starches on gelatinization and glycemic response was studied. Both starches showed to possess different fine structures. Starch 1 exhibited a typical B-type X-ray diffraction pattern, while Starch 2 exhibited an X-ray diffraction pattern suggesting the presence of imperfections of the general B-type crystalline structure (peak at 5.5 degrees 2 theta was absent), hence disarraying the structure order. This difference was reflected in the gelatinization behavior and consequently in the glycemic response. Starch 2 started to melt at lower temperature than Starch 1 (e.g. T-o was 60.9 and 61.84 degrees C, respectively, to native starches), and residual gelatinization enthalpy (Delta H) of Starch 2 was always smaller than that of Starch 1 when heated at 54-65 degrees C for 10 min. Glycemic response was increased as gelatinization degree (DG) increased in starches independent from the native crystalline structure (area under curve = 2.59 x DG-75.83, R-2=0.986; maximum concentration of postprandial blood glucose=0.042 x DG-0.23, R-2=0.935). Results suggested that native crystalline structure of isolated potato starch affects the glycemic response of heated starches by affecting the gelatinization behavior. (C) 2011 Elsevier Ltd. All rights reserved.
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    Effect of three-component interactions among starch, lipids and proteins on the glycemic response
    (Elsevier, 2018) Parada, Javier; Santos, Jose L.
    For humans, starch is considered the most important dietary energy source worldwide, and can be usually found forming part of a matrix with lipids and proteins. So, knowledge regarding the role of interactions between such food components is crucial to design healthier food, since aspects such as resultant microstructure determine the product properties, either sensorial or nutritional ones, among others. This chapter reviews the microstructural principles of interactions between starch, lipids, and proteins in foods as well as their effect on postprandial glycemic response, considering some intrinsic differences among human individuals. The idea that foods without rapidly digestible starch will not mandatorily generate the lowest postprandial glycemic response will be discussed, highlighting that food microstructure, which modulates starch digestion, would play an important role in the final healthy property of starchy foods. 
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    Glycemic Response after Starch Consumption in Relation to Salivary Amylase Activity and Copy-number Variation of AMY1 Gene
    (2015) Alberti, Gigliola; Parada, Javier; Rodrigo Cataldo, L.; Vega, Javier; Aguilera, Concepción M.; Alvarez-Mercado, Ana I.; Hodgson Bunster, María Isabel; López, Alberto; Angellotti, Isidora; Gil, Angel; Santos Martín, José Luis
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    In vitro Digestibility and Glycemic Response of Potato Starch is Related to Granule Size and Degree of Gelatinization
    (WILEY, 2009) Parada, Javier; Aguilera, Jose M.
    Starch granule microstructure affects the digestion of starch and its nutritional impact; however, the exact relationship between both factors is not clear. This study reports quantitative relationships between granule size (length and polygonal area), degree of gelatinization (DG), in vitro digestibility (by enzymatic methods), and glycemic response of potato starch granules gelatinized to various extents by heating at several constant temperatures in the range of 55 to 65 degrees C. DG measured by differential scanning calorimetry was closely related with heating temperature (R-2 = 0.997), size parameters of granules (measured by image analysis), in vitro digestion, and in vivo glycemic response (R-2 of adjusted models > 0.9); shape parameters of granules (measured by image analysis) were not related with DG. Results demonstrate that DG of starch strongly affects its digestibility in vitro, and may influence the postpandrial glycemic response. Future studies should be performed to investigate the effect of potato starch gelatinization on the nutritional impact at other temperatures and in more complex matrices.
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    Microstructure of starch-based meals with either palm or soybean oils alter in vitro starch digestibility with no major effects on glycaemic responses
    (2019) Bravo, Carolina; Santos Martín, José Luis; Castillo, Gabriel; Olivares, Gabriela; Parada, Javier
    Glycaemic response (GR) to starch-based meals depends on their food composition and microstructure. We studied the effect of palm and soybean oils on the microstructure of a solid starch-oil-gluten matrix, on the starch gelatinisation and in vitro digestibility. Additionally, a pilot cross-over study was carried out to assess GR after eating gelatinised starch/gluten-based foods with the addition of either palm or soybean oil in 8 young non-diabetic female volunteers (ISRCTN39636850). Both types of foods generated similar starch gelatinisation temperature. Starch/gluten-based food with soybean oil had rougher microstructure compared to food with palm oil, showing a higher initial and lower final in vitro digestion. Administration of starch/gluten-based meals with either palm or soybean oils to volunteers show very similar postprandial glucose or insulin responses. In conclusion, differences in fatty acid composition changes food microstructure and in vitro starch digestibility, with no major effects on glycaemic responses in female volunteers.
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    Microstructure, mechanical properties, and starch digestibility of a cooked dough made with potato starch and wheat gluten
    (ELSEVIER, 2011) Parada, Javier; Aguilera, Jose M.
    Processed starch-protein foods may exhibit a variety of microstructures, hence different mechanical properties and starch digestibility but the relation between these parameters is yet to be resolved. This paper reports on the effect of three processing factors (extent of mixing, cooking temperature and cooking time) on the microstructure of a model dough system consisting of potato starch, wheat gluten and water, and the in vitro digestibility of starch in the matrix as well as the relationship between microstructure and starch digestibility. Samples subjected to a high mixing level showed lower rupture stress and rupture strain (decreased by 54% and 46%, respectively), a higher residual gelatinization enthalpy of starch (Delta H), and a higher amount of birefringent starch granules (increased by 25%). Additionally, at higher mixing level the in vitro starch digestibility resulted in 24% less slowly available glucose whereas the rapidly available glucose increased by 25%. These findings were related to the original microstructure of the dough examined by confocal scanning laser microscopy. (C) 2011 Elsevier Ltd. All tights reserved.
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    Phenolic content of honey reduces in vitro starch digestibility
    (2016) Parada, Javier; Santos Martín, José Luis; Cañoles, Paula; Manquián, Nimia
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    The effect of vacuum frying on starch gelatinization and its in vitrodigestibility in starch-gluten matrices
    (2016) Contardo Hernández Ingrid Macarena; Parada, Javier; Leiva Campusano, Ángel; Bouchon Aguirre, Pedro Alejandro
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    The impact of cooking and delivery modes of thymol and carvacrol on retention and bioaccessibility in starchy foods
    (2016) Aravena, Gabriela; García, Iga; Muñoz, Ociel; Pérez C., José Ricardo; Parada, Javier