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In the present study, isothermal microcalorimetry was introduced as a tool to investigate properties of starch retrogradation during the first 24 h. The study was made on purified amylose and amylopectin from corn, as well as on native starches, such as wheat, potato, maize, waxy maize and amylomaize, differing in their amylose content. The results were obtained in the form ofP-t traces (thermal powervs. time), and integration of these traces gave a net exothermic enthalpy of reaction, caused by the crystallization of amylose and amylopectin. TheP-t traces reflected the quantities of amylose and amylopectin in the starch studied. Depending on the amylose content and the botanical source of the starch, the rate of crystallization of amylose was high and predominated over that of amylopectin during the first 5–10 h. The contribution from amylose crystallization to the measured exothermic enthalpy was very substantial during this period. After ∼10 h, amylose crystallized at a lower constant rate. During the first 24 h, amylopectin crystallized at a low steady rate. The exothermic enthalpies obtained by the isothermal microcalorimetric investigations during the first 24 h of retrogradation were generally low in relation to the endothermic melting enthalpies observed by differential scanning calorimetry (DSC) measurements after 24 h of storage. The discrepancies in enthalpy values between the two methods are discussed in relation to phase separation and the endothermic effects owing to the decrease in polymer-water interactions when polymer-rich regions in the starch gel separate. Besides the exothermic enthalpies obtained, theP-t traces also made it possible to study the initial gelation properties of amylose from different botanical sources. The present study further demonstrated that isothermal microcalorimetry can provide a possible way to investigate the antistaling effect of certain polar lipids, such as sodium dodecylsulphate (SDS) and 1-monolauroyl-rac-glycerol (GML), when added to starches of different botanical origin. The net exothermic heat of reaction for starch retrogradation during the first 24 h was decreased when GML or SDS was added to the starch gels. The recordedP-t traces also showed how the effect of the added lipid influenced different periods during the first 24 h of starch retrogradation, and that the effect depended mainly on the amylose content, the botanical source of the starch, and the type of lipid used. When GML or SDS was added to waxy maize, the isothermal microcalorimetric studies clearly indicated some interaction between amylopectin and the polar lipids. These results concerning the action of anti-staling agents are further discussed in relation to the helical inclusion complexes formed between amylose-polar lipid and amylopectin-polar lipid.

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Machado, N. O.: Management of duodenal perforation post-endoscopic retrograde cholangiopancreatography. When and whom to operate and what factors determine the outcome? A review article. JOP, 2012, 13 , 18

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.: Controlled trial of urgent endoscopic retrograde cholangiopancreatography and endoscopic sphincterotomy versus conservative treatment for acute pancreatitis due to gallstones. Lancet, 1988, 2 , 979–983. London N. J

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Acta Veterinaria Hungarica
Authors: Davide Monaco, Miguel Batista, Olga Amann, Barbara Padalino, Wouter Pieters, Mariacristina Morelli, Gianluca Accogli, Salvatore Desantis, and Giovanni Michele Lacalandra

that ES have been collected with retrograde flushing (RF) in many animal species, in the DC this technique has been described only in two studies ( Abdoon et al., 2013; Turri et al., 2013 ). However, other than sperm viability and total motility, the

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Summary

The abnormal solvation behavior of retrograde condensate oil has been investigated by inverse gas chromatography, by modelling the temperature dependence of linear solvation energy relationships (LSER) under conditions of constant gas chromatographic column pressure. The results obtained (values of the r and s coefficients in LSER) reveal increased repulsion between the volatile gas and the condensate oil as the temperature is reduced.

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The neuroscience research front on Retrograde Amnesia is taken as an example to demonstratethe capabilities of co-citation mapping in combination with peer review. In an interview with awell-known expert in the field the co-citation map was confirmed as a good representation of thespeciality. The expert was able to identify and comment on different regions of the map and hecould validate important documents in the cluster core and research front as well as the mainactors on institutional and national level. The bibliometric data inspired the expert to outline thecognitive and social "history" of the speciality.

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Abstract  

High hydrostatic pressure (HHP) has been investigated as an alternative to thermal processing for food preservation. HHP has been known to affect high molecular weight polymers causing phase change. Starch is gelatinized at a pressure on the order of 600–700 MPa, at 25 °C. Gelatinized starch recrystallizes during storage affecting the texture and shelf life of food products. The effect of HHP processing on the crystallization of starches from different botanical origins during storage at 4 and 23 °C was investigated. Crystallization kinetics of HHP treated wheat and corn starch gels were compared using DSC. The effect of crystallization on structure was evaluated in terms of storage modulus. The rate of retrogradation depended on the storage temperature (23 °C and 4 °C) and the botanical origin of the starch. The least crystallization was observed in HHP treated wheat starch stored at 23 °C. The storage modulus increased with crystallization of starch.

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structure and thermal behavior including plasticization, gelatinization, and retrogradation is crucial. Differential scanning calorimetry (DSC) and hot-stage polarized optical microscopy are methods of choice for studying starch gelatinization. The

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The aim of experiments was to characterize the neurons of the autonomic chain that innervates the nipple and the mammary gland of lactating rats using retrograde transynaptic virus labeling and neurotransmitter and neuropeptide immunohistochemistry. Two days after injection of green fluorescence protein labeled virus in two nipples and underlying mammary glands, labeling was observed in the ipsilateral paravertebral sympathetic trunk and the lateral horn. Three days after inoculation the labeling appeared in the brain stem and the hypothalamic paraventricular nucleus. Above the spinal cord the labeling was bilateral. A subpopulation of virus labeled cells in the paraventricular nuclei synthesized oxytocin. Labeled neurons in the lateral horn showed cholinergic immunoreactivity. These cholinergic neurons innervated the paravertebral ganglia where the virus labeled neurons were partially noradrenergic. The noradrenergic fibers in the mammary gland innervate the smooth muscle wall of vessels, but not the mammary gland in rats. The neurons in the lateral horn receive afferents from the brain stem, and paraventricular nucleus and these afferents are noradrenergic and oxytocinergic. New findings in our work: Some oxytocinergic fibers may descend to the neurons of the lateral horn which innervate noradrenergic neurons in the paravertebral sympathetic trunk, and in turn these noradrenergic neurons reach the vessels of the mammary gland.

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attempts to give a survey on the novel, special applications of different types of CDs in food technology and nutrition, especially on the beneficial effects of CDs on starchy foods, affecting the retrogradation of starch/amylose systems, providing improved

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