Search results for "IMPREGNATION"
showing 10 items of 13 documents
Firming of fruit tissues by vacuum infusion of pectin methylesterase: Visualisation of enzyme action
2008
; Apple pieces were vacuum-impregnated with either a pectin methylesterase (PME) and calcium solution or with water prior to pasteurization. Pasteurized apple pieces impregnated with PME and calcium showed a significantly higher firmness. Moreover, solid state C-13 NMR spectroscopy of apple cell wall residues revealed an increase of their molecular rigidity. Exogenous PME addition involved a decrease from 82% to 45% of apple pectin degree of methyl-esterification. Microscopic observations of apple slices immunolabelled with antibodies specific for pectins showed that (i) demethyl-esterification was more intense in the cell wall region lining intercellular spaces (demonstrating a key role f…
New trials in the consolidation of waterlogged archaeological wood with different acetone-carried products
2011
Some acetone-carried consolidants for waterlogged archaeological wood were tested in order to evaluate treatments able to save time and energy. In details, colophony (rosin), two esterified colophonies (Rosin 100® and Rosin 459®), a mixture of colophony with PEG 3400 and a vinyl acetate - vinyl versate copolymer (Vinavil 8020S®) were tested. The treatments were carried out at temperatures of 20 and 35 °C on waterlogged maritime pine, elm, oak and beech. The materials came from the archaeological Site of the ancient ships of Pisa (Tuscany, Italy) and were dated back to VII cent. BC II cent. AD. To evaluate the processes, equilibrium moisture content and dimensional stability of treated woo…
DSC AND TGA TO EVALUATE THE SELECTIVE IMPREGNATION OF WATERLOGGED ARCHAEOLOGICAL WOODS WITH POLY(ETHYLENE) GLYCOLS MIXTURES
2012
Within the cultural heritage field the wood conservation of waterlogged archaeological objects aims at preventing the collapsing of the wooden structure (upon drying) the degradation of which is related to the Taxon but also to the chemical and biological nature of the site. The refilling of the wood cavities with a consolidant, which confers robustness and stability, is an interesting strategy for the conservation methods of waterlogged archaeological objects. To this purpose, using different impregnation methods, waterlogged archaeological woods were consolidated by using aqueous mixtures of poly(ethylene) glycols with different molecular weights (PEG 400 and PEG 4000) as well as mixtures…
Sustainable development of apple snack formulated with blueberry juice and trehalose
2021
Novel products that carry concrete and relevant health benefits, with texture and flavor not substantially different from already available products, are generally well accepted by consumers. Vacuum impregnation is a non-thermal technology that allows the enrichment of fruit with different ingredients in solution. The characteristic of the resulting product is a combination of both the solid matrix and the impregnation solution. This work aimed at: (i) evaluating the effect of trehalose on anthocyanin retention after drying of apple snacks vacuum impregnated with blueberry juice
Study of Water Distribution, Textural and Colour Properties of Cold Formulated and Air-Dried Apple Snacks
2022
Vacuum impregnation is considered a cold formulation technology since it allows the incorporation of a desired functional compound into porous plant tissue without applying any heat. It is widely used in combination with the drying process to obtain added-value snacks. The aim of this work was to evaluate the effect of two trehalose concentrations (5 and 10% w/w) on: (i) the water state and texture evolution during the air drying (50 °C, 8 h) of apple snacks vacuum impregnated with blueberry juice, and on (ii) the colour of the final dried apple snacks. The results of nuclear magnetic resonance (NMR) showed that trehalose affects the water mobility of the samples during drying especially af…
Perineural pattern of aggregation of cellular blue nevus: probable histoarchitectural reminiscence of histogenesis.
2008
A striking feature of cellular blue nevus consists in the presence, in its histologic picture, of numerous hypertrophic nerves and nerve-like figures, positive for histochemical and immunohistochemical methods for nerve fibers and myelin sheaths. These findings, first described in Masson's original article and repeatedly highlighted in the past for their possible histogenetic significance, are currently considered as merely coincidental. However, the thin conventional histologic sections, catching only short tracts of the nerves, preclude a correct observation of their route and do not allow us to verify if there is an architectural relationship between them and the nevus as a whole. With t…
No invasive methodology to produce a probiotic low humid apple snack with potential effect against Helicobacter pylori
2012
Abstract A probiotic low humid apple snack with potential effect against the infection caused by Helicobacter pylori has been developed from apple (cv. Granny Smith) and mandarin juice with a high microbial content of Lactobacillus salivarius spp . salivarius , by vacuum impregnation and hot air drying techniques. The moisture content reached in the final product (0.144 ± 0.012 g water · g sample - 1 ) ensured stability, and although the drying process affected the microbial content, the concentration in the final product (9.486 ± 0.013) × 10 7 CFU g dry sample - 1 ) was sufficient to confirm that with this procedure it is possible to obtain a stable probiotic fruit with a low moisture c…
Interaction of Ni/SiO2 with thiophene.
2009
Abstract The interaction between Ni/SiO 2 (18 wt%) and thiophene was studied by thermal gravimetric analysis (TGA) and in a fixed-bed reactor. The samples were prepared by incipient wetness impregnation and reaction was realized in hydrogen flow at 280–360 °C in the presence of 10–40 mbar of thiophene. It is found that sulfidation of Ni is not complete in TGA experiments and the maximum achievable transformation degree depends not only on the temperature and thiophene pressure, but also on the sample weight and the gas flow rate. The maximum transformation degree is shown to vary reversibly when conditions are changed. Analysis of the reaction products during sulfidation in a fixed-bed reac…
Reaction of thiophene with mono- and bimetallic Ni–Co particles supported on γ-Al2O3 and HDS activities of obtained sulfides
2009
Abstract Reaction between thiophene and M/γ-Al2O3 (20 wt.%, M = Ni, Co, 2Ni–Co and 2Co–Ni) was studied by thermal gravimetric analysis (TGA) and by sulfidation in a fixed bed microreactor. The samples were prepared by incipient wetness impregnation followed by drying and reduction in hydrogen flow at 450 °C. Formation of bimetallic particles in samples containing both Ni and Co was confirmed by HRTEM with EDX analysis. The reaction with thiophene (20 or 40 mbar) was done at 360 °C in hydrogen atmosphere. TGA of the reaction with thiophene revealed that the initial rate of sulfidation drops sharply when going from Ni/γ-Al2O3 to Co/γ-Al2O3 (by a factor of 40 under used conditions). It follows…
Vacuum impregnation as a tool to introduce biopreservatives in gilthead sea bream fillets (Sparus aurata)
2015
Abstract The aim of this study was to determine the possible technological uses of biopreservation and vacuum impregnation techniques to extend shelf life of gilthead sea bream fillets. Two impregnation media were studied: a solution containing lactic acid bacteria (LAB) and a nisin solution. Vacuum impregnation was carried out at 4 °C. Fillets were immersed in a vessel containing the impregnation solution and vacuum was applied during 5 min. After this time atmospheric pressure was restored leaving samples under the liquid for 5 min more. Weight gain, physico-chemical properties (moisture, pH, water activity and TVBN), color and microbiological counts were studied during 15 days of storage…