Gastric emptying of ordinary food: effect of antrum on particle size

1980 ◽  
Vol 239 (3) ◽  
pp. G133-G135 ◽  
Author(s):  
J. H. Meyer
Keyword(s):  
Particle Size ◽  
Small Intestine ◽  
Gastric Emptying ◽  
Chemical Composition ◽  
Quantitative Methods ◽  
Food Effect ◽  
Physical Nature ◽  
Gamma Cameras ◽  
Early Results ◽  
Rapid Labeling

The lack of reliably quantitative methods has delayed understanding how the stomach empties and processes foods. Rapid refinement of gamma cameras has prompted the development of several methods for labeling of ordinary foods with radionuclides. These methods allow rapid labeling with tightly adherent nuclides and are safe for studies both in animals and humans. Nuclide-labeled foods have also permitted detailed analyses of gastric emptying in animals prepared with chronic duodenal fistulas. Early results indicate that the stomach retains foods until these are fragmented into particles smaller than 0.5 mm in diameter, and that this sieving is achieved in the antral region of the stomach. The speed of fragmentation of foods into particles of this size as well as the speed of emptying appear to be closely regulated by chemoceptive mechanisms in the small intestine, which can inhibit these processes. Thus, chemical composition of the meal regulates gastric emptying as well as the physical nature of the food, which determines how easily it can be fragmented by the stomach.

scholarly journals Influencing Factors of the Mineral Carbonation Process of Iron Ore Mining Waste in Sequestering Atmospheric Carbon Dioxide

2021 ◽  
Vol 13 (4) ◽  
pp. 1866
Author(s):  
Noor Allesya Alis Ramli ◽  
Faradiella Mohd Kusin ◽  
Verma Loretta M. Molahid
Keyword(s):  
Carbon Dioxide ◽  
Particle Size ◽  
Chemical Composition ◽  
Iron Ore ◽  
Divalent Cations ◽  
Mining Industry ◽  
Mining Waste ◽  
Aluminum Silicate ◽  
Mineral Carbonation ◽  
Carbonation Process

Mining waste may contain potential minerals that can act as essential feedstock for long-term carbon sequestration through a mineral carbonation process. This study attempts to identify the mineralogical and chemical composition of iron ore mining waste alongside the effects of particle size, temperature, and pH on carbonation efficiency. The samples were found to be alkaline in nature (pH of 6.9–7.5) and contained small-sized particles of clay and silt, thus indicating their suitability for mineral carbonation reactions. Samples were composed of important silicate minerals needed for the formation of carbonates such as wollastonite, anorthite, diopside, perovskite, johannsenite, and magnesium aluminum silicate, and the Fe-bearing mineral magnetite. The presence of Fe2O3 (39.6–62.9%) and CaO (7.2–15.2%) indicated the potential of the waste to sequester carbon dioxide because these oxides are important divalent cations for mineral carbonation. The use of small-sized mine-waste particles enables the enhancement of carbonation efficiency, i.e., particles of <38 µm showed a greater extent of Fe and Ca carbonation efficiency (between 1.6–6.7%) compared to particles of <63 µm (0.9–5.7%) and 75 µm (0.7–6.0%). Increasing the reaction temperature from 80 °C to 150–200 °C resulted in a higher Fe and Ca carbonation efficiency of some samples between 0.9–5.8% and 0.8–4.0%, respectively. The effect of increasing the pH from 8–12 was notably observed in Fe carbonation efficiency of between 0.7–5.9% (pH 12) compared to 0.6–3.3% (pH 8). Ca carbonation efficiency was moderately observed (0.7–5.5%) as with the increasing pH between 8–10. Therefore, it has been evidenced that mineralogical and chemical composition were of great importance for the mineral carbonation process, and that the effects of particle size, pH, and temperature of iron mining waste were influential in determining carbonation efficiency. Findings would be beneficial for sustaining the mining industry while taking into account the issue of waste production in tackling the global carbon emission concerns.

Tracking physical breakdown of rice- and wheat-based foods with varying structures during gastric digestion and its influence on gastric emptying in a growing pig model

2021 ◽  
Author(s):  
Joanna Nadia ◽  
Alexander G. Olenskyj ◽  
Natascha Stroebinger ◽  
Suzanne M. Hodgkinson ◽  
Talia G. Estevez ◽  
...  
Keyword(s):  
Particle Size ◽  
Gastric Emptying ◽  
Pig Model ◽  
Moisture Uptake ◽  
Gastric Digestion ◽  
Food Structure ◽  
Growing Pig ◽  
Effect Of Food

There is currently a limited understanding of the effect of food structure on physical breakdown and gastric emptying of solid starch-based foods during gastric digestion. Moisture uptake, pH, particle size,...

scholarly journals Variation of the Chemical Composition of Waste Cooking Oils upon Bentonite Filtration

Resources ◽  
2019 ◽  
Vol 8 (2) ◽  
pp. 108 ◽  
Author(s):  
Alberto Mannu ◽  
Gina Vlahopoulou ◽  
Paolo Urgeghe ◽  
Monica Ferro ◽  
Alessandra Del Caro ◽  
...  
Keyword(s):  
Particle Size ◽  
Chemical Composition ◽  
Solid Phase ◽  
Volatile Fraction ◽  
X Ray Diffraction ◽  
Specific Chemical ◽  
Waste Cooking Oils ◽  
Main Components ◽  
Cooking Oils ◽  
Chemical Groups

The chemical composition and the color of samples of waste cooking oils (WCOs) were determined prior to and after filtration on two different pads of bentonite differing in particle size. The volatile fraction was monitored by headspace solid-phase microextraction (HS-SPME) coupled with gas-chromatography, while the variation of the composition of the main components was analyzed by 1H NMR. Both techniques allowed the detection of some decomposition products, such as polymers, terpenes, and derivatives of the Maillard process. The analysis of the chemical composition prior to and after bentonite treatment revealed a tendency for the clays to retain specific chemical groups (such as carboxylic acids or double bonds), independent of their particle size. A pair comparison test was conducted in order to detect the sensory differences of the intensity of aroma between the WCO treated with the two different bentonites. In addition, characterization of the bentonite by means of powder X-ray diffraction (XRD) and thermogravimetric measurements (TG) was performed.

Intraluminal lipids modulate avian gastrointestinal motility

1995 ◽  
Vol 269 (2) ◽  
pp. R445-R452 ◽  
Author(s):  
V. Martinez ◽  
M. Jimenez ◽  
E. Gonalons ◽  
P. Vergara
Keyword(s):  
Small Intestine ◽  
Oleic Acid ◽  
Gastric Emptying ◽  
Electrical Activity ◽  
Transit Time ◽  
Gastrointestinal Motility ◽  
Phase Iii ◽  
Intestinal Transit Time ◽  
Speed Of Propagation ◽  
Spike Bursts

Infusion of lipids into the ileum delays gastric emptying and intestinal transit time in some species. The aim of this study was to characterize the actions of intraluminal lipid infusion on gastrointestinal electrical activity in chickens. Animals were prepared for electromyography with chronic electrodes in stomach, duodenum, and small intestine. Two catheters were chronically placed in the esophagus and ileum to infuse equimolar doses of either oleic acid (OA) or triolein (TO). Both OA and TO, esophageally infused, inhibited the frequency of the gastroduodenal cycle and increased the frequency of antiperistaltic spike bursts in the duodenum. Ileal infusion of OA, but not of TO, produced the same effects. Both esophageal and ileal OA infusion increased the duration of the migrating myoelectric complex (MMC) and decreased the speed of propagation of phase III. In conclusion, intraluminal infusion of lipids modulates gastrointestinal motility by decreasing the frequency of the gastric cycle, increasing duodenogastric refluxes, and elongating the MMC. These actions could delay gastric emptying and increase transit time, which suggests the presence of an "ileal brake" mechanism similar to that described in mammals.

scholarly journals Influence of Brazilian pine seed flour addition on rheological, chemical and sensory properties of gluten-free rice flour cakes

2018 ◽  
Vol 48 (6) ◽  
Author(s):  
Mônica Ikeda ◽  
Carlos Wanderlei Piler Carvalho ◽  
Cristiane Vieira Helm ◽  
Henriette Monteiro Cordeiro de Azeredo ◽  
Rossana Catie Bueno de Gogoy ◽  
...  
Keyword(s):  
Particle Size ◽  
Chemical Composition ◽  
Experimental Design ◽  
Rice Flour ◽  
Gluten Free ◽  
Araucaria Angustifolia ◽  
Sensory Acceptance ◽  
Seed Flour ◽  
Flour Sample ◽  
Paste Viscosity

ABSTRACT: Brazilian pine seeds (pinhão) are gluten-free seeds produced by the native pine species named Araucaria angustifolia. In this study, gluten-free cake mixes composed of Brazilian pine seed flour and rice flour were developed. The cake mixes were produced following a Simplex Centroid experimental design, with rice flour and Brazilian pine seed flour contents ranging from 50 to 100% and from 0 to 50%, respectively. Mixes were analyzed for chemical composition, apparent paste viscosity, and particle size distribution. The resulting cakes were analyzed for sensory acceptance, texture, specific volume and chemical composition. The Brazilian pine seed flour showed a peak viscosity on heating of 1.761Pa.s against 4.747Pa.s for the 100% rice flour sample. The variation of firmness of cakes decreased with increasing percentage of Brazilian pine seed flour. Cakes containing Brazilian pine seed flour at 25-37.5% of the formulation presented highest overall acceptance.

Gastric emptying of nondigestible solids in dogs: a hydrodynamic correlation

1990 ◽  
Vol 258 (1) ◽  
pp. G65-G72 ◽  
Author(s):  
P. J. Sirois ◽  
G. L. Amidon ◽  
J. H. Meyer ◽  
J. Doty ◽  
J. B. Dressman
Keyword(s):  
Particle Size ◽  
Gastric Emptying ◽  
Gravitational Constant ◽  
Particle Density ◽  
Particle Diameter ◽  
High Viscosity ◽  
Fluid Viscosity ◽  
Fluid Flow Rate ◽  
Hydrodynamic Correlation ◽  
Viscosity Polymer

The influence of particle size, particle density, fluid viscosity, and fluid flow rate on the gastric emptying of nondigestible solids was investigated in five dogs with chronically placed fistulas. Six hundred and fifty particles of 13 different size and density combinations were administered simultaneously with 500 ml of either normal saline or low-, medium-, or high-viscosity polymer solutions. The canine stomach was found to discriminate between these solids on the basis of size and density at all levels of viscosity above saline. The observed patterns of emptying are consistent with the hypothesis that gastric emptying of nondigestible solids is governed in part by hydrodynamics and correlate well with the gastric-emptying coefficient (GEC), a dimensionless grouping of variables that takes the form GEC = (Dpy/Dp) [g(rho f - rho p)Dp2]/[eta (nu)] where [g(rho f - rho p)] is particle buoyancy consisting of fluid (rho f) and particle (rho p) densities and g, the gravitational constant; (Dp) is the particle diameter, (Dpy) the estimated pyloric diameter, eta the fluid viscosity, and (nu) the average linear velocity of fluid exiting the stomach.

scholarly journals Nanomaterials and nanotechnology for the delivery of agrochemicals: strategies towards sustainable agriculture

2022 ◽  
Vol 20 (1) ◽  
Author(s):  
Changcheng An ◽  
Changjiao Sun ◽  
Ningjun Li ◽  
Bingna Huang ◽  
Jiajun Jiang ◽  
...  
Keyword(s):  
Particle Size ◽  
Food Security ◽  
Chemical Composition ◽  
Labor Cost ◽  
Small Particle Size ◽  
Agricultural Systems ◽  
The Stability ◽  
New Applications ◽  
Chemical Pesticides ◽  
Improve Food Security

AbstractNanomaterials (NMs) have received considerable attention in the field of agrochemicals due to their special properties, such as small particle size, surface structure, solubility and chemical composition. The application of NMs and nanotechnology in agrochemicals dramatically overcomes the defects of conventional agrochemicals, including low bioavailability, easy photolysis, and organic solvent pollution, etc. In this review, we describe advances in the application of NMs in chemical pesticides and fertilizers, which are the two earliest and most researched areas of NMs in agrochemicals. Besides, this article concerns with the new applications of NMs in other agrochemicals, such as bio-pesticides, nucleic acid pesticides, plant growth regulators (PGRs), and pheromone. We also discuss challenges and the industrialization trend of NMs in the field of agrochemicals. Constructing nano-agrochemical delivery system via NMs and nanotechnology facilitates the improvement of the stability and dispersion of active ingredients, promotes the precise delivery of agrochemicals, reduces residual pollution and decreases labor cost in different application scenarios, which is potential to maintain the sustainability of agricultural systems and improve food security by increasing the efficacy of agricultural inputs. Graphical Abstract

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