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1.
Trends Food Sci Technol ; 109: 94-102, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34728899

RESUMO

BACKGROUND: The ability of small- and medium-sized enterprises in the food industry (FSMEs) in cultivating resilience against the COVID-19 pandemic is vital food security. However, there is limited supply chain resilience literature to guide FSMEs in overcoming disruptions caused by pandemic. SCOPE AND APPROACH: This review aims to provide a broad view of SCRes reactive strategies for FSMEs in dealing with crises in the context of COVID-19. Attention is given to the literature on resilience in other types of supply chain and situated in the context of food settings. The factors are monitored or controlled to contribute to FSME resiliency.Key findings and conclusion: Four quadrants, i.e., (1) rapid with low cost, (2) rapid with high cost, (3) slow with low cost and (4) slow with high cost, are offered based on the limitations and the time needed to react, and the strategies of each quadrant are explained in depth. This review also provides a better understanding of and guidance on reactive strategies for SCRes as options for FSMEs in dealing with the COVID-19 pandemic. This review suggests future directions as extensions based on the logical flow of this review.

2.
Chemistry ; 22(1): 302-9, 2016 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-26608231

RESUMO

For the first time, a versatile electrolyte bath is described that can be used to electrodeposit a wide range of p-block elements from supercritical difluoromethane (scCH2 F2 ). The bath comprises the tetrabutylammonium chlorometallate complex of the element in an electrolyte of 50×10(-3)  mol dm(-3) tetrabutylammonium chloride at 17.2 MPa and 358 K. Through the use of anionic ([GaCl4 ](-) , [InCl4 ](-) , [GeCl3 ](-) , [SnCl3 ](-) , [SbCl4 ](-) , and [BiCl4 ](-) ) and dianionic ([SeCl6 ](2-) and [TeCl6 ](2-) ) chlorometallate salts, the deposition of elemental Ga, In, Ge, Sn, Sb, Bi, Se, and Te is demonstrated. In all cases, with the exception of gallium, which is a liquid under the deposition conditions, the resulting deposits are characterised by SEM, energy-dispersive X-ray analysis, XRD and Raman spectroscopy. An advantage of this electrolyte system is that the reagents are all crystalline solids, reasonably easy to handle and not highly water or oxygen sensitive. The results presented herein significantly broaden the range of materials accessible by electrodeposition from supercritical fluid and open up the future possibility of utilising the full scope of these unique fluids to electrodeposit functional binary or ternary alloys and compounds of these elements.

3.
Phys Chem Chem Phys ; 18(21): 14359-69, 2016 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-27166921

RESUMO

We present investigations into a variety of supporting electrolytes and supercritical fluids probing the phase and conductivity behaviour of these systems and show that they not only provide sufficient electrical conductivity for an electrodeposition bath, but match the requirements imposed by the different precursors and process parameters, e.g. increased temperature, for potential deposition experiments. The two supercritical fluids that have been explored in this study are difluoromethane (CH2F2) and 1,1-difluoroethane (CHF2CH3). For CH2F2, the phase behaviour and electrical conductivity of eight ionic compounds have been studied. Each compound consists of a cation and an anion from the selected candidates i.e. tetramethylammonium ([N(CH3)4](+)), tetrabutylammonium ([N((n)C4H9)4](+)), 1-ethyl-3-methylimidazolium ([EMIM](+)) and 1-butyl-3-methylimidazolium ([BMIM](+)) for cations, and tetrakis(perfluoro-tert-butoxy)aluminate ([Al(OC(CF3)3)4](-)), chloride (Cl(-)), trifluoromethyl sulfonimide ([NTf2](-)) and tris(pentafluoroethyl)trifluorophosphate ([FAP](-)) for anions. For CHF2CH3, [N((n)C4H9)4][BF4] and [N((n)C4H9)4][B{3,5-C6H3(CF3)2}4] have been investigated for comparison with the previously measured solubility and conductivity in CH2F2. We have found that [N((n)C4H9)4][Al(OC(CF3)3)4], [N((n)C4H9)4][FAP] and [N(CH3)4][FAP] have much higher molar conductivity in scCH2F2 at similar conditions than [N((n)C4H9)4][BF4], a widely used commercial electrolyte. Additionally, scCHF2CH3 shows potential for use as the solvent for supercritical fluid electrodeposition, especially at high temperatures since high density of this fluid can be achieved at lower operating pressures than similar fluids that can be used to produce electrochemical baths with comparable conductivity.

4.
Food Res Int ; 164: 112283, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36737895

RESUMO

Zingiber officinale Roscoe is an excellent source of bioactive compounds, mainly gingerols and shogaols compounds, that associated with various bioactivities including antioxidant, anticancer, anti-inflammatory, antimicrobial, and antibiofilm. Zingiber officinale Roscoe found its application in the food, pharmaceutical, and cosmeceutical industries. The demand for a high quality of ginger oleoresin extracts based on the contents of gingerols and shogaols compounds for a health-benefit has dramatically increased. Various extraction techniques, including the conventional and advanced extraction techniques for gingerols and shogaols have been reported based on the literature data from 2012 to 2022. The present review examines the functional composition and bioactivities of Zingiber officinale Roscoe and the advanced green extraction technologies. Some variations in the quantity and quality of gingerols and shogaols compounds are because of the extraction method employed. This review provides a depth discussion of the various green advanced extraction technologies and the influences of process variables on the performance of the extraction process. Lower temperature with a short exposure time such as ultrasound-assisted and enzyme-assisted extraction, will lead to high quality of extracts with high content of 6-gingerol. High thermal processing, such as microwave-assisted and pressurized liquid extraction, will produce higher 6-shogaol. Meanwhile, supercritical fluid extraction promotes high quality and the safety of extracts by using non-toxic CO2. In addition, challenges and future prospects of the extraction of ginger oleoresin have been identified and discussed. The emerging green extraction methods and technologies show promising results with less energy input and higher quality extracts than conventional extraction methods.


Assuntos
Anti-Infecciosos , Zingiber officinale , Extratos Vegetais
5.
PLoS One ; 17(4): e0266673, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35413072

RESUMO

Propolis is a good source for flavonoids, however, their recovery is challenging, as it is a waxy material. This study investigated edible oils virgin coconut oil (VCO), corn oil (CO), and ghee (G) as co-extractants for the supercritical carbon dioxide (scCO2) extraction of flavonoids from the propolis. The extraction of flavonoids using 20% VCO as co-extractant with scCO2 (25 g/min) for 210 min at 150 bar and 50°C was found to be the most appropriate, yielding a total flavonoid content (TFC) of 11.7 mg/g and 25% TFC recovery. At a higher temperature (60°C) and pressure (250 bar and 350 bar), the propolis became softer and compressed causing the extractions to retrograde. The extraction curves correlated to the diffusion model with 1.6% (AARD). The matrix diffusivities increased from 4.7 × 10-11 m2/s (scCO2) to 6.9 × 10-11-21.4 × 10-11 m2/s upon the addition of edible oils. Thus, edible oils could be used with scCO2 to improve the flavonoid extraction from propolis.


Assuntos
Cromatografia com Fluido Supercrítico , Própole , Dióxido de Carbono , Flavonoides , Óleos , Óleos de Plantas
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