Search results for "Colorants"
showing 6 items of 6 documents
Transfers of small analytes in a multiphasic stirred fruit yoghurt model
2007
International audience; The transfer of small analytes in a multiphasic stirred fruit yoghurt model, made of a pectin gel aimed to mimic fruit pieces and of a dairy gel done with milk acidified by glucono-δ-lactone hydrolysis, have been studied. The concentration gradients between the pectin gel and the dairy gel were the driving force for the migration of small analytes (i.e. water, protons and colorants). Water migrated from the dairy to the pectin gel, causing modifications in the water content of both gels and an equilibration of their water activity at 0.938±0.003. Inversely, protons migrated from the pectin to the dairy gel. These changes in composition of both gels being likely to ha…
Conception et synthèse de nouvelles sondes fluorogéniques à coeur Bodipy pour la détection
2020
Therefore this project is aimed at the development of novel improved multi-analyte fluorogenic probes for heavy metals ions and bioanalytes within the framework “AND” fluorescent molecular logic gates concept. The biothiols and cations of Cd(II), Pb(II), Cr(III) and Cu(II) heavy metals will be selected as the targeted analytes. To the best of our knowledge, no “AND” molecular logic gates using metal ions besides Zn(II), Hg(II), Ca(II) inputs, likewise no multi-analyte probes for biothiols along with heavy metal cations, has been described in the literature. While the development of a highly sensitive and selective recognition of thiols and metal cations has emerged as a significant interest…
Recovery of colorants from red prickly pear peels and pulps enhanced by pulsed electric field and ultrasound
2016
Abstract The aim of this work was to evaluate the potential of the non-conventional pre-treatments; pulsed electric fields (PEFs) and ultrasounds (USNs), to enhance the extraction of red colorants from red prickly pear ( Opuntia stricta Haw.) peels and pulps. The overall goal was to valorize the thick part of the fruit, being discarded for fruit's consumption. PEF and USN treatments were first optimized using fruit slices, followed by a supplementary aqueous extraction (+ SAE) up to 1 h. The optimal conditions were then applied for peels and pulps, separately. Results showed that PEF + SAE and USN + SAE enhanced significantly the extraction of red colorants (betanin/isobetanin), compared to…
Optimization of Polyphenols' Recovery from Purple Corn Cobs Assisted by Infrared Technology and Use of Extracted Anthocyanins as a Natural Colorant i…
2022
An ecofriendly extraction technology using infrared (IR) irradiation Ired-Irrad® was applied to purple corn cobs to enhance polyphenol recovery for the first time. The IR extraction efficiency was compared to that of the water bath (WB) method. Response surface methodology (RSM) using a central composite design was conducted to determine the effect of the experimental conditions (extraction time and treatment temperature) and their interactions on the total polyphenol and anthocyanin yields. Optimal extraction of total phenolic compounds (37 mg GAE/g DM) and total monomeric anthocyanins (14 mg C3G/g DM) were obtained at 63 °C for 77 min using IR as an extraction technique and water as a sol…
Color study of historic silks
2022
The chemical characterization of silk textiles of historic value may be necessary to achieve a better understanding of the production processes applied, to evaluate their preservation, to detect manipulations or forgeries, and to value the combination of tradition and innovation in contemporary manufacturing techniques. The main objective of this work was to study four historical silks from the Garín collection, all of them from the 20th century, although with 19th century designs. To this end, non-invasive spectroscopic and microscopy techniques were applied in order to obtain information on the dyes used during their production and their link with those used in the silk industry in previo…
Advances in solution-processed near-infrared light-emitting diodes
2021
A summary of recent advances in the near-infrared light-emitting diodes that are fabricated by solution-processed means, with coverage of devices based on organic semiconductors, halide perovskites and colloidal quantum dots.