Effect of moisture content on flowability: Angle of repose, tilting angle, and Hausner ratio

Author(s):  
Haim Kalman
2013 ◽  
Vol 2 (6) ◽  
pp. 24
Author(s):  
A. S. Oyerinde ◽  
A. P. Olalusi

<p>The effect of moisture content on some physical and mechanical properties of two varieties of tigernuts (<em>Cyperus esculentus</em>) was investigated. These properties include: geometric dimensions, linear dimensions, 1000 tuber weight, bulk density, tuber size, sphericity, angle of repose, porosity, coefficient of static friction and compressive strength. The moisture content levels used were 20, 25, 30, 35 and 40% wet basis (wb), and the two tigernut varieties used were yellow and brown types. The linear dimension, geometric diameter, sphericity, 1000- tuber weight, bulk density and angle of repose in both varieties increased with increasing moisture content. The average length, width and thickness of the yellow variety increases more than the brown variety at the determined moisture contents. True density of the yellow variety increased while the brown variety decreased with increase in moisture content. The porosity of the yellow variety reduces with increase in moisture content from 45.95 at 20% mc to 42.4 at 40% mc, while the brown variety decreased from 42.72 at 20% mc to 30.77 at 40% moisture content. The yellow variety had bigger size tubers than the brown variety and this has serious implications in packing, handling and transportation issues.</p>


2016 ◽  
Vol 44 (2) ◽  
Author(s):  
Shrikant Baslingappa Swami ◽  
N.J. Thakor A.M. Gawai

<p>The physical properties, viz., geometric diameter, surface area, sphericity, volume, bulk density, true density and angle of repose was measured for  four  cashew varieties <em>viz</em>., <em>Vengurle 1, Vengurle 3, Vengurle 4</em>  and <em>Vengurle 7</em> at different moisture content (15 to 87% db). For <em>Vengurle</em> 1 as the moisture content increased, the physical properties i.e., geometric mean diameter, volume, surface area, true density and angle of repose increased from 20.8 to 22.1 mm, 3485 to 4416 mm<sup>3</sup>, 1355 to 1540 mm<sup>2</sup>, 984 to 1030 kg m<sup>-3</sup> and 32 to 37˚, respectively. The sphericity and bulk density decreased from 74.2 to 71.4 per cent and 490 to 418 kg m<sup>-3</sup> respectively. For <em>Vengurle 3</em> geometric mean diameter, volume, surface area, true density and angle of repose increased from 27.2 to 28.6 mm, 7912 to 9169 mm<sup>3</sup>, 2320 to 2567 mm<sup>2</sup>, 1020 to 1048 kg m<sup>-3</sup> and 33 to 35.5˚, respectively. The sphericity and bulk density decreased from 75.5 to 75.2 per cent and 531 to 470 kg m<sup>-3</sup> respectively. For <em>Vengurle 4</em> the geometric mean diameter, volume, surface area, true density and angle of repose increased from 21.0 to 24.1mm, 3362 to 5113 mm<sup>3</sup>, 1391 to 1828 mm<sup>2</sup>, 970 to 1030 kg m<sup>-3</sup> and 32.5 to 38˚,  respectively. The sphericity and bulk density decreased from 65.8 to 66.8 per cent, 517 to 462 kg m<sup>-3</sup>, respectively. For <em>Vengurle 7</em> the geometric mean diameter, volume, surface area, true density and angle of repose increased from 24.2 to 24.9 mm, 5102 to 5547 mm<sup>3</sup>, 1840 to 1941 mm<sup>2</sup>, 998 to 1045 kg m<sup>-3</sup> and 33 to 38˚, respectively. The sphericity and bulk density decreased from 65.4 to 65.8 per cent, 518 to 438 kg m<sup>-3</sup>, respectively.</p>


Author(s):  
María de J. Perea-Flores ◽  
Miriam F. Fabela-Morón ◽  
Adolfo A. Rayas-Amor ◽  
Rigoberto V. Pérez-Ruíz ◽  
Rafael Ruíz-Hernández ◽  
...  

Objective: Evaluate the physical-chemical properties and characterize the microstructure of four varieties of traditional Mexican chili (Capsicum annuum L.) powders: “Arbol”, “Guajillo”, “Piquin” and “Mole ranchero” (Ancho chili). Design/methodology/approach: Physical-chemical properties of chili powders were evaluated by means of moisture content, particle size, aerated and tapped bulk density, Carr index, Hausner ratio, angle of repose (flow properties), capsaicin, and carotenoids content. Microstructure of samples was characterized by Confocal Laser Scanning Microscopy and Scanning Electron Microscopy. ANOVA analysis and Tukey test were performed to evaluate the significant statistical difference between samples at 95% of confidence level. Results: “Arbol”, “Guajillo”, “Piquin” and “Mole Ranchero” chili powders presented a cohesive behavior respect to its flow properties related to aerated and tapped bulk density, angle of repose, Carr Index, and Hausner ratio values under moisture content between 6.59-14.48 gH2O/100g d.s. “Arbol” and “Piquin” chili powders presented the higher capsaicin content, while “Guajillo” and “Mole ranchero” showed the higher carotenoids content. FTIR spectra confirmed the presence of secondary amide, phenolic groups, alkanes, and aliphatic chains that belong to capsaicin structure at specific absorption bands. Microstructure of chili powders presented particles with surface imperfections as cracks and dents, and smooth surface that influence physical-chemical and flowability properties. Limitations on study/implications: Hight moisture content affect the physical-chemical properties, flowability and microstructure of traditional Mexican chili powders. Findings/conclusions: Moisture content between 6.59 and 14.48 gH2O/100g d.s. influences the physical-chemical properties, flowability and microstructure of traditional Mexican chili powders. To improve physical-chemical properties and flowability behavior of chili powders is required that moisture content be lower than 6.59 H2O/100g d.s.


Polymers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1616
Author(s):  
Vincenzo Titone ◽  
Antonio Correnti ◽  
Francesco Paolo La Mantia

This work is focused on the influence of moisture content on the processing and mechanical properties of a biodegradable polyester used for applications in injection molding. The pellets of the biodegradable polyester were exposed under different relative humidity conditions at a constant temperature before being compression molded. The compression-molded specimens were again placed under the above conditions before the mechanical testing. With all these samples, it is possible to determine the effect of moisture content on the processing and mechanical properties separately, as well as the combined effect of moisture content on the mechanical properties. The results obtained showed that the amount of absorbed water—both before processing and before mechanical testing—causes an increase in elongation at break and a slight reduction of the elastic modulus and tensile strength. These changes have been associated with possible hydrolytic degradation during the compression molding process and, in particular, with the plasticizing action of the moisture absorbed by the specimens.


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