The valorization of industrial food byproducts by means of environment-friendly extraction method... more The valorization of industrial food byproducts by means of environment-friendly extraction methods is becoming a major interest because of its environmental and economic values. In this study, the efficiency of many technologies, such as ultrasounds (US), microwaves (MW), and infrared (IR), was compared, in terms of polyphenol yield and bioactivity from apricot pomace. IR was the most effective method with the highest polyphenol (10 mg GAE/g DM), flavonoid (6 mg CE/g DM), and tannin (3.6 mg/L) yields. In terms of efficacy, IR was followed by MW, US, then solid-liquid (S/L) extraction. IR extract from apricot pomace exhibited the highest inhibitory activity against all the studied gram-positive strains (Methicillin Resistant Staphylococcus aureus, Staphylococcus aureus, Methicillin-resistant Staphylococcus epidermidis, and Staphylococcus epidermidis) and a one gram-negative strain (Escherichia coli). Moreover, IR extracts had by far the highest antiradical activity (AC) (40%) followe...
Mycotoxins are generally found in food, feed, dairy products, and beverages, subsequently present... more Mycotoxins are generally found in food, feed, dairy products, and beverages, subsequently presenting serious human and animal health problems. Not surprisingly, mycotoxin contamination has been a worldwide concern for many research studies. In this regard, many biological, chemical, and physical approaches were investigated to reduce and/or remove contamination from food and feed products. Biological detoxification processes seem to be the most promising approaches for mycotoxins removal from food. The current review details the newest progress in biological detoxification (adsorption and metabolization) through microorganisms, their biofilms, and enzymatic degradation, finally describing the detoxification mechanism of many mycotoxins by some microorganisms. This review also reports the possible usage of microorganisms as mycotoxins’ binders in various food commodities, which may help produce mycotoxins-free food and feed.
The high diversity of phenolic compounds (PC) found in food matrices makes it challenging to anal... more The high diversity of phenolic compounds (PC) found in food matrices makes it challenging to analyze their bioavailability and their impact on health and functional metabolism. It is well recognized that PC do modulate the composition of the gut microbiota (GM), however, the literature still lacks significant data concerning the link between the metabolic fate of the ingested compounds and their bioactivity, mainly when considering the secondary metabolites produced. In this study, we assessed the metabolic fate of PC for a period covering 14 months of daily intake to identify the metabolites that could be responsible for the effects of PC on the GM observed in our previous work. Urinary analysis of polyphenol metabolites was performed using a high resolution mass spectrometry LC-QTOF-MS method. Among the sixteen metabolites identified, 3-hydroxyphenylacetic acid and 2-(4-hydroxyphenyl) propionic acid were detected simultaneously and, therefore, correlated with the growth of Bifidobacterium in the rat GM. In addition, Daidzedin, detected only at 14 months post-treatment, mostly interfered with the growth inhibition of Clostridium (Cluster I). In conclusion, the impact of the long-term intake of PC on rat GM seems to be related to specific metabolites produced after ingestion of the parental compounds and this may also be due to their additional synergistic effects.
Aflatoxins (AF) are carcinogenic metabolites produced by different species of Aspergillus which r... more Aflatoxins (AF) are carcinogenic metabolites produced by different species of Aspergillus which readily colonize crops. AFM1 is secreted in the milk of lactating mammals through the ingestion of feedstuffs contaminated by aflatoxin B1 (AFB1). Therefore, its presence in milk, even in small amounts, presents a real concern for dairy industries and consumers of dairy products. Different strategies can lead to the reduction of AFM1 contamination levels in milk. They include adopting good agricultural practices, decreasing the AFB1 contamination of animal feeds, or using diverse types of adsorbent materials. One of the most effective types of adsorbents used for AFM1 decontamination are those of microbial origin. This review discusses current issues about AFM1 decontamination methods. These methods are based on the use of different bio-adsorbent agents such as bacteria and yeasts to complex AFM1 in milk. Moreover, this review answers some of the raised concerns about the binding stabilit...
Grape harvest date is determined according to the technological and phenolic maturities. These pa... more Grape harvest date is determined according to the technological and phenolic maturities. These parameters were calculated for different red grape (Vitis vinifera L.) varieties (Cabernet Sauvignon, Merlot, Syrah, Cabernet Franc) over four years (2008, 2009, 2010, and 2011) (642 samples). Titratable acidity and sugar content of the grapes were used to determine the technological maturity, whereas Glories (1 and 2) and ITV (Institut Technique de la Vigne et du Vin) methods were used to monitor their phenolic maturity. The ITV method allows the monitoring of phenolic maturity by the quantification of total polyphenol index and anthocyanins, while the Glories method enables the quantitative evolution of extractable anthocyanins and tannins of the grapes. A correlation was shown between the harvest dates obtained by both ITV and Glories (R 2 = 0.7-0.93). Phenolic maturity of grapes can, therefore, be optimized by the application of both ITV and Glories. Similarly, a correlation was observed between technological and phenolic harvest dates. The effect of climate on the phenolic content of grapes was also studied. The highest temperatures (up to 25 • C) accompanied by the lowest rainfall (null value), induced the maximal concentration of polyphenols in grapes. Thermal and water stresses were also shown to enhance the grapes' polyphenolic production.
OATAO is an open access repository that collects the work of some Toulouse researchers and makes ... more OATAO is an open access repository that collects the work of some Toulouse researchers and makes it freely available over the web where possible.
Phenolic compounds are naturally extracted molecules used nowadays for several industrial applica... more Phenolic compounds are naturally extracted molecules used nowadays for several industrial applications such as food preservatives and neutraciticals; thus industrial needs are in constant growth. Optimization of phenolic compounds (PC) and monomeric anthocyanins (MA) extraction from grape berries using response surface methodology was here achieved. Cabernet Sauvignon (CS) wine grapes (Vitis vinifera L. cv. Cabernet Sauvignon) are a rich source of anti-radical phenols, extractable as dietary supplements. However, efficiency of extraction strongly depends on specific experimental conditions. In this work, the comparison between two extraction mixtures, Acetone/Water (A/W) and Methanol/Water (M/W) and the effects of three critical variables-Extraction Time (between 8 and 88 h), Extraction Temperature (between 1˚C and 35˚C) and Solvent Content (between 63% and 97%)-on Phenolic Compounds Yield (PCY) and Monomeric Anthocyanins Yield (MAY) were studied using Response Surface Methodology (RSM). Process conditions maximizing the PCY were found to be 87% A/W solvent content, after 88 h incubation at 26˚C, and those of the MAY were found to be 97% M/W solvent content, after 8 h incubation at 1˚C. In addition, chromatographic profiles of extracts showed very different affinities of the phenolic compounds families to the experimental conditions employed. This process advantages are: low percentage of organic solvent used, high quality of extracted molecules thanks to low temperature treatment, very low energy consumption and low cost of needed machinery. At industrial scale, it may be used as promising technique for the extraction of bioactive compounds from plant or byproduct material such as from wine or grape juice industries.
The current work concerns the optimization process of phenolic compounds solid liquid extraction ... more The current work concerns the optimization process of phenolic compounds solid liquid extraction from grape byproducts at high temperatures and short incubation times. The effect of five experimental parameters (solidliquid ratio, particle size, time, temperature and solvent mixture) mostly believed to affect the extraction process was undertaken. A first response surface methodology experimental design was used to optimize the solid-liquid ratio and milling time parameters. A second design was used for the optimization of the quantitative and qualitative parameters. The quantitative parameters studied are: total phenolic compounds, flavonoid content, total monomeric anthocyanin composition and tannin concentration. The qualitative parameters analyzed are: antiradical activity and antioxidant capacity. The second design was based on the use of time, temperature and solvent mixture as optimization parameters. The assays were first conducted separately revealing the best experimental conditions for the maximization of each response variable alone. A simultaneous response surface methodology of all the responses taken together was then conducted, showing the optimal extraction conditions to be: 93 minutes at 94˚C and in 66% ethanol/water solvent. The maximal response values obtained for each parameter are: Total Phenolic Compounds yield (5.5 g GAE/100g DM), Flavonoid Content (5.4 g GAE/100g DM), Total Monomeric Anthocyanin yield (70.3 mg/100g DM), Tannin Concentration (12.3 g/L), Antiradical Activity (67.3%) and Total Antioxidant Capacity (393 mgAAE/L). All of the optimal values were acquired at 3 mL/g solid-liquid ratio and 6.8 min milling time. The obtained extracts could be used as natural bioactive compounds in several industrial applications.
In this study phenolic compounds extraction from grape byproducts was conducted using pure water ... more In this study phenolic compounds extraction from grape byproducts was conducted using pure water as a solvent. High temperatures and low time incubation periods were used in the aim of reducing the cost of the process and heightening the phenolic compounds yield. Response surface methodology (RSM) was realized to study the effect of time and temperature on crushed and uncrushed grape pomace. The phenolic content was evaluated considering the quantity (total phenolics (TPC), flavonoids (FC), total monomeric anthocyanins (TMA) and tannins (TC)), and quality (antiradical activity (AA) and antioxidant capacity (AC)) of the extracts. High temperature low time extraction design used in this study was compared to the extraction process at moderate temperatures with relatively long periods of time. This was proved to ameliorate the quantitative extraction of phenolic compounds from grape pomace without affecting their bioactivity. Moreover, multiple response optimization showed the optimal extraction parameters to be 81˚C and 140 minutes for the unmilled pomace samples, and 88˚C and 5 minutes for the milled. TPC, FC, TMA, TC, AA and AC are almost the same for both optimums. Thus the possibility of replacing the milling process by the extraction time prolongation (for the unmilled pomace) of 135 minutes seems to be very plausible. HPLC analysis showed different quantity and diversity of extracted phenolics for the optimums. However this difference did not significantly affect the overall activity, showing that PC in the different extracts act in complete synergy all together leading to important biological properties. The obtained results using the extraction strategy adopted in this work could lead to several industrial applications.
Application of the new process of controlled instantaneous pressure drop (DIC) to the drying/text... more Application of the new process of controlled instantaneous pressure drop (DIC) to the drying/texturization of fish: effects on physicochemical characteristics of the final product. In order to improve fish drying process, the operation of hot air dehydration coupled to the new process of texturization "(DIC)" (Controlled Instantaneous Pressure Drop) was applied. Two types of fish were studied: the Atlantic salmon (Salmo salar) and the white tuna (Thunnus albacore) chosen as fatty and semi-fatty types, respectively. The influence of DIC treatment on the end product physicochemical biochemical characteristics was studied. The analyses of sample density, rehydration, water activity, lipids, proteins, mineral content and color were used to compare the DIC treated product with those obtained by traditional methods of drying such as air, vacuum and freeze-drying. The DIC treatment enhances highly the functional quality of the product and preserves well the nutritional value of the raw material.
Innovative Food Science & Emerging Technologies, 2009
The study investigated the intensification and improvement of oil extraction from orange peel thr... more The study investigated the intensification and improvement of oil extraction from orange peel through a thermomechanical process: the Instantaneous Controlled Pressure Drop (briefly D.I.C process). This process involves subjecting orange peel for a short time to steam pressure, followed by an instantaneous decompression to vacuum at 50 mbar. Central composite design was used to study the combined effects of processing steam pressure (1-7 bar; which corresponds to a temperature ranging between 100°C and 162 °C respectively), processing time (0.3-3.7 min.) and initial moisture content of orange peel before thermomechanical oil extraction (9.8-60.2 % on dry material basis). The quantitative analysis, have been undertaken on oil present in orange peels, after processing. Correlation analysis of the mathematical regression model indicated that quadratic polynomial model could be employed to optimize the extraction of oil from orange peel. From response surface plots, the three variables exhibited a linear effect with the strongest effect for the processing pressure. The optimum reaction conditions selected with response surface analysis were as follows: steam processing pressure: 6.6 bar, processing time: 3.68 min, initial moisture content: 53.6 % d.m basis. Under these conditions, experimental yield of orange peel oil was close to predicted value (99 %) calculated from the polynomial response surface model equation. A kinetic study indicated that extraction performed by D.I.C process is clearly quicker than conventional steam distillation method.
While world energy demand has certainly decreased with the beginning of the COVID-19 pandemic in ... more While world energy demand has certainly decreased with the beginning of the COVID-19 pandemic in 2020, the need has been significantly on the rise since 2021, all as the world’s fossil fuel resources are depleting; it is widely accepted that these resources emit greenhouse gases (GHG), which are the leading cause for the climate crisis. The main contributors to global warming are manufacturing, energy, and agriculture. The agricultural sector is composed of diversified and potential mobilizable sources of waste which can become an attractive alternative to fossil fuels for energy production, and thus sequester and use carbon. Therefore, a paradigm shift towards more sustainable energy alternatives, efficient waste management, and new technologies is necessary. One good solution is the energetic valorization of lignocellulosic biomass (LCB) which can also originate from agricultural wastes. The biomass consists of cellulose, hemicellulose, and lignin, which are sources of fermentable...
The study investigated the intensification and improvement of oil extraction from orange peel 12 ... more The study investigated the intensification and improvement of oil extraction from orange peel 12 through a thermomechanical process: the Instantaneous Controlled Pressure Drop (briefly D.I.C 13 process). This process involves subjecting orange peel for a short time to steam pressure, 14 followed by an instantaneous decompression to vacuum at 50 mbar. Central composite design 15 was used to study the combined effects of processing steam pressure (1-7 bar; which 16 corresponds to a temperature ranging between 100°C and 162 °C respectively), processing time 17 (0.3 -3.7 min.) and initial moisture content of orange peel before thermomechanical oil 18 extraction (9.8 -60.2 % on dry material basis). The quantitative analysis, have been undertaken 19 on oil present in orange peels, after processing. Correlation analysis of the mathematical 20 regression model indicated that quadratic polynomial model could be employed to optimize the 21 extraction of oil from orange peel. From response surface plots, the three variables exhibited a 22 linear effect with the strongest effect for the processing pressure. The optimum reaction 23 conditions selected with response surface analysis were as follows: steam processing pressure: 24 6.6 bar, processing time: 3.68 min, initial moisture content: 53.6 % d.m basis. Under these 25 conditions, experimental yield of orange peel oil was close to predicted value (99 %) calculated 26 from the polynomial response surface model equation. A kinetic study indicated that extraction 27 performed by D.I.C process is clearly quicker than conventional steam distillation method. 28 29 30 31
A procedure, Controlled Sudden Decompression (D etente Instantan ee Contrôl ee DIC â ) has been d... more A procedure, Controlled Sudden Decompression (D etente Instantan ee Contrôl ee DIC â ) has been developed to impart a porous structure to partially dried pieces of food by expanding them. In this paper, the DIC cycle was optimized for use with special food products. The establishment of an initial vacuum phase prior to the steam treatment, a treatment by step-wise increases in temperature and an atmospheric air injection phase enabled us to process product pieces in a thick layer, very heat-sensitive products or other food products with a low hardening temperature. The physical attributes evaluated were the expansion ratio and color of three vegetables: potatoes, carrots and onions.
Quality of dried vegetables texturized by Controlled Sudden Decompression (D etente Instantan ee ... more Quality of dried vegetables texturized by Controlled Sudden Decompression (D etente Instantan ee Contrôl ee DIC â ) was studied through the expansion ratio, the color and the degree of cooking. This study was realized as a function of the four main experimental parameters: saturated steam pressure, treatment time, water content of the product before treatment and the thickness of the pieces of the raw product. These parameters are of primary importance in determining the quality of the final product. The behavior of the matter vis-a-vis the treatments was also investigated. It was found that pressure had the highest effect with final product volumes being 2.2-4.5 times those after drying with hot air only. An optimum treatment time of 25 s was defined although for potato, with a denser structure, it was 45 s. General patterns for the variation in expansion ratio as a function of the operating parameters are proposed.
ABSTRACT: A new texturizing process, Controlled Sudden Decompression (Détente Instantanée Contrôl... more ABSTRACT: A new texturizing process, Controlled Sudden Decompression (Détente Instantanée Contrôlée “DIC®“), has been developed to improve the quality of hot-air dried food. The process involves a treatment under high pressure of steam followed by an extremely rapid decompression to the vacuum. Coupled with a drying step, this process provides high-quality finished products for a similar overall cost to hot-air drying alone. The definition, design, and achievement of the appropriate equipment have already been dealt with. In this study, 2 parameters directly related to DIC expansion were examined: initial pressure (before decompression) in the vacuum tank and the decompression duration. Impact of structural modifications on the rate of dehydration was also quantified.
Application du nouveau procédé de séchage/ texturation par Détente Instantanée Contr,lée (DIC) aux poissons : impact sur les caractéristiques physicochimiques du produit fini
The colour of dried fish is a measure of their biochemical and structural degradation. In this st... more The colour of dried fish is a measure of their biochemical and structural degradation. In this study a novel method for measuring colour by image processing is proposed which can be used in the ÔL à a à b à ' space to determine the mean colour and standard deviation of heterogeneous samples with a high degree of consistency and reproducibility. Image processing of the fish samples coupled with a statistical (discriminant) analysis could separate the effect of the drying processes on the mean colour from their effect on the heterogeneity of colour. Finally, chroma variance was shown to be the only way of statistically separating (by analysis of variance) the samples according to the drying technique used. Compared with sensory analysis, measuring colour by image processing was therefore found to be reliable and efficient and could easily be integrated into an industrial production process.
Séchage-texturation des fraises par le procédé de Détente Instantanée : contrôlée couplé au séchage par convection. Optimisation à l'aide de la méthodologie des plans d'expériences
Sciences Des Aliments, 2001
... Auteur(s) / Author(s). NOUVIAIRE Armelle (1) ; LOUKA Nicolas (1) ; REZZOUG Sid-Ahmed (1) ; AL... more ... Auteur(s) / Author(s). NOUVIAIRE Armelle (1) ; LOUKA Nicolas (1) ; REZZOUG Sid-Ahmed (1) ; ALLAF Karim (1) ; Affiliation(s) du ou des auteurs / Author(s) Affiliation(s). ... Experimental design. ; Optimization. ; Process improvement. ; Small fruits. ; Heat treatment. ; Physical dressing ...
A Study of Dehydration of Fish Using Successive Pressure Drops (DDS) and Controlled Instantaneous Pressure Drop (DIC
Drying Technology, 2004
... Drying technology , 11(3): 451470. [CSA] [Taylor & Francis Online], [Web of Science ... ... more ... Drying technology , 11(3): 451470. [CSA] [Taylor & Francis Online], [Web of Science ... Application de Terrain au Mali 213 pMassy, , France: Thèse de l'Ecole nationale supérieure des industries agricoles et alimentaires. View all references 66. Osei-Opare, F. and Kukah, A. 1989. ...
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