Preparation of BaTiO3 powders using supercritical CO2 drying of gels

The aim of this study was to compare the sensory quality and acceptance of dried ready-to-eat beetroot snacks as a result of different drying methods applied: supercritical CO2-drying (scCO2-drying), frying, and freeze-drying. Descriptive sensory analysis, quality rating (10 assessors), and consumer acceptance testing (n = 102) were performed. Mean overall quality scores within the range of “very good” quality were found only in non-precooked scCO2-dried samples which were characterized by typical magenta color, low level of shape and surface deformations, pronounced brittleness and crispiness, and good rehydration during mastication. The other samples were in the range of “good” quality. The pre-cooking step before scCO2-drying negatively influenced the sensory quality parameters, particularly appearance. Around 60% of tested consumers showed a preference for the fried and non-precooked scCO2-dried samples. The drivers of liking were mostly related to the characteristics of the product, which was salted, fried, and crispy, with an oily and overburnt flavor, i.e., the product most similar to commercial potato chips products. Freeze-drying had a negative effect primarily on appearance and flavor. According to the sensory evaluation conducted, direct scCO2-drying without a pre-cooking step showed itself as a promising alternative drying technology in the production of dried beetroot snacks.

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Structural Changes Upon Supercritical Co2-Drying of Gels

Sol-Gel Processing and Applications ◽

10.1007/978-1-4615-2570-7_25 ◽

1994 ◽

pp. 295-302 ◽

Cited By ~ 3

Author(s):

U. Klett ◽

T. Heinrich ◽

A. Emmerling ◽

J. Fricke

Keyword(s):

Supercritical Co2 ◽

Structural Changes ◽

Supercritical Co2 Drying

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Effect of Supercritical CO2 Drying on Moisture Transfer and Wood Property of Eucalyptus urophydis

Forests ◽

10.3390/f11101115 ◽

2020 ◽

Vol 11 (10) ◽

pp. 1115

Author(s):

Lin Yang ◽

Honghai Liu

Keyword(s):

Moisture Content ◽

Supercritical Co2 ◽

Moisture Transfer ◽

Content Distribution ◽

Wood Property ◽

Drying Rate ◽

Extractive Content ◽

Moisture Content Distribution ◽

Bordered Pits ◽

Supercritical Co2 Drying

Wood dried using supercritical CO2 has unique properties because water is removed directly from the cell lumens through the cycling between supercritical and gas phases. Eucalyptus urophydis green wood was dried by supercritical CO2 at 50 °C and pressure of 10, 20, and 30 MPa; the effect of supercritical CO2 drying on moisture content distribution and transfer, as well as the permeability and extractive content of the wood, was investigated. The results showed that the supercritical CO2 drying rate was high, showing the highest drying rate at 20 MPa and the lowest at 10 MPa. Drying rate increased with pressure below 20 MPa in this study; drying rate represented no positive relation to pressure over 20 Mpa. Moisture content distribution was more uneven in the low-pressure drying conditions and in the middle transverse section of the specimens. The moisture content gradient in tangential was greater than that in longitudinal, especially for the drying of 10 MPa, indicating that water was removed mainly in the former direction of wood. More extractives were removed from wood at higher pressure during supercritical CO2 drying. Bordered pits were broken up more at higher pressure conditions. The decreased extract yields and increased amount of opened bordered pits increased the permeability of the wood after supercritical CO2 drying.

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Preparation of SiO2 and NiO/Al2O3 aerogels by supercritical CO2 drying and their catalytic activity

Microporous Materials ◽

10.1016/0927-6513(96)00009-0 ◽

1996 ◽

Vol 7 (1) ◽

pp. 41-49 ◽

Cited By ~ 8

Author(s):

Motonobu Goto ◽

Yoshinori Machino ◽

Tsutomu Hirose

Keyword(s):

Catalytic Activity ◽

Supercritical Co2 ◽

Supercritical Co2 Drying

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Supercritical CO2 drying of food matrices

Proceedings of 21th International Drying Symposium ◽

10.4995/ids2018.2018.7753 ◽

2018 ◽

Author(s):

S. Spilimbergo ◽

A. Zambon ◽

T. M. Vizzotto ◽

G. Morbiato ◽

M. Toffoletto ◽

...

Keyword(s):

Supercritical Co2 ◽

Supercritical Drying ◽

Microbial Inactivation ◽

Process Conditions ◽

Drying Methods ◽

Drying Process ◽

Promising Alternative ◽

Supercritical Co2 Drying ◽

Conventional Drying ◽

Drying Efficiency

This work explore the use of supercritical CO2 drying as alternative technique for the obtainment of pasteurized and high quality dried product. Several tests were conducted on animal, vegetable and fruit matrixes in order to investigate the effectiveness of SC-CO2 drying process at different process conditions. Design of experiment was performed to find the optimal process conditions for vegetable and fruit matrices, using the final water activity of the products as key indicator for the drying efficiency. The inactivation of naturally present microorganisms and inoculated pathogens demonstrated the capability of SC-CO2 drying process to assure a safe product. Moreover, retention of nutrients was compared with conventional drying methods. Results suggest that supercritical drying is a promising alternative technology for food drying. Keywords: supercritical drying; carbon dioxide; food drying; microbial inactivation

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Effects of Supercritical CO2 Drying and Photoresist Strip on Low-k Films

MRS Proceedings ◽

10.1557/proc-766-e8.20 ◽

2003 ◽

Vol 766 ◽

Author(s):

R.F. Reidy ◽

Zhengping Zhang ◽

R.A. Orozco-Teran ◽

B.P. Gorman ◽

D.W. Mueller

Keyword(s):

Dielectric Constant ◽

Porous Materials ◽

Transport Properties ◽

Supercritical Co2 ◽

Polar Molecule ◽

Interlayer Dielectric ◽

Highly Porous Materials ◽

Supercritical Co2 Drying ◽

Low K ◽

Highly Porous

AbstractFuture interlayer dielectric (ILD) requirements necessitate reductions in dielectric constant to 2.1 within four years. Due to gaseous-like transport properties and near liquid-like densities, supercritical methods have been developed to dry and strip resist from these highly porous materials. Although a non-polar molecule, the solvating capability of supercritical CO2 (SCCO2) can be tailored by varying pressure, temperature, and co-solvents. This flexibility has been employed to remove photoresist and moisture from porous low-k films. The results of these experiments have been characterized using FTIR, ellipsometry, and SEM.

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