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The present study was designed to evaluate the nutritional composition of melon pulp Maazoun variety, in order to explore its potential attitude as a natural source of nutrients and bioactive molecules. The chemical characterization showed that the pulp was rich in moisture, carbohydrate, dietary fibers, and minerals, as well as carotenoids and phenolic compounds. The chromatographic analysis indicated that amentoflavone (16.14 mg/100 g) and gallic acid (13.56 mg/100 g) were the most abundant phenolic compounds. Melon flesh has an interesting volatile profile in which, mostly esters and alcohols are considered as the key odorants of this appreciated fruit. Melon juice was filtered through crossflow microfiltration that provides more translucent juice and accentuation of yellow color. During clarification process, the permeate flux was reduced by 50% in approximately 40 min. Results proved that the richness of melons in nutrients and bioactive phytochemicals makes them useful as a potential source of antioxidants and suitable as nutraceutical supplements.

The aim of this study was to investigate the phytochemical composition and biological properties of Tunisian propolis from four different regions: Kasserine, Béja, Kèf and Monastir. Ethanolic extracts of propolis were prepared using two extraction methods; solvent and ultrasonic extraction. Total phenolics, flavonoids, ABTS free radical and hydroxyl radicals scavenging abilities, anti-inflammatory, anti-hypertensive, as well as antimicrobial activities of propolis extracts were determined. Identification and quantification of phenolic and flavonoid compounds were performed by using both HPLC-UV and HPLC-ESI-MS. The results revealed high contents of total phenolics and flavonoids and polyphenols extraction was more efficient by sonication. Caffeic acid phenethyl ester (CAPE), galangin, and genistein were the major identified compounds. Antihypertensive activity, evaluated in propolis extracts for first time by HPLC-UV, was higher than 90% for all extracts. Tunisian propolis is an important natural source of polyphenols and flavonoids. The best extraction method was ultrasonic for antioxidants and most of biological activities; conventional method seems to be more suitable for anti-inflammatory activity. Propolis from Béja contains the highest amount of antioxidants and have a stronger potential biological activities. Tunisian propolis could be, therefore, a promising raw material for food and pharmaceutical industry.

The present study is conducted to investigate the effect(s) of ultrasonic pretreatment on the extraction of essential oils from dried leaves of lemongrass (Cymbopogon flexuosus) by hydro-distillation. The drying process was carried out within a forced convective dryer at 50 °C and a drying air velocity of 1 m/s. Using a response surface methodology (RSM) based on central composite design with the face centered, the obtained optimum conditions were as follows: an ultrasound pretreatment for 25 min within a power of 250 W, at 50 °C. Modeling showed that all factors (time, power and temperature) were found to be highly significant in the extraction process (p

This study aimed to evaluate the characteristic features, phenolic compounds and thermal analysis of melon seed oil (Maazoun variety), in order to determine its potential applications in food or pharmaceutical industries. The physicochemical properties of the seed oil revealed a high degree of unsaturation. The average contents of carotenoid and chlorophyll were 2.43 mg/kg and 5.70 mg/kg, respectively. The main fatty acids of melon seed oil were linoleic acid (68.98%) and oleic acid (15.84%), which makes this oil nutritionally valuable. Furthermore, trilinolein (LLL), accounted for 28.99% and constitutes the most abundant triacylglycerol. A chromatographic analysis showed that amentoflavone and luteolin-7-glycoside were the major phenolic compounds. A thermal analysis of melon seed oil was performed by differential scanning calorimetery (DSC). The results of sensorial properties indicated that melon seed oil is appreciated by tasters. The findings suggested that because of its composition, melon seed oil could be used successfully as an alternative source in the food and nutraceutical industries as a functional ingredient. El objetivo de este estudio fue la caracterización, evaluación de compuestos fenólicos y el análisis térmico del aceite de semillas de melón (variedad Maazoun), con el fin de conocer sus potenciales aplicaciones en la industria alimentaria o farmacéutica. Las propiedades fisicoquímicas del aceite de semilla mostraron un alto grado de insaturación. El contenido promedio de carotenoides y clorofila fue de 2,43 mg/kg y 5,70 mg/kg, respectivamente. Los principales ácidos grasos del aceite de semilla de melón fueron el linoleico (68,98%) y oleico (15,84%), lo que hace que este aceite sea nutricionalmente valioso. Además, la trilinoleína (LLL) que representó el 28,99% constituye el triacilglicerol más abundante. El análisis cromatográfico mostró que amentoflavona y luteolin-7-glucósido eran los principales compuestos fenólicos. El análisis térmico del aceite de semilla de melón se realizó mediante calorimetría diferencial de barrido (DSC). Los resultados de las propiedades sensoriales indicaron que los catadores aprecian el aceite de semilla de melón. Los hallazgos sugieren que, debido a su composición, el aceite de semilla de melón podría utilizarse con éxito como una fuente alternativa en la industria alimentaria y nutracéutica como ingrediente funcional.

This study focused on the formulation of food products, based on sesame and carob. The possibility of developing blends from sesame paste and carob molasses, using molasses concentrations of 30, 40 and 50%, at 60, 70 and 80°Brix, respectively, has been studied. The blend prepared with 50% carob molasses at 60°Brix was found to be the most acceptable product, according to a sensory acceptability test. Sesame paste, supplemented with carob molasses, was evaluated for physical quality (oil separation, colour and texture) and nutritional composition (moisture, sugar, protein, fat, ash and polyphenols). Physical analysis showed that the addition of carob molasses to sesame paste improved its emulsion stability, changed its colour from beige to brown and modified its texture from fluid to solid. Nutritional analysis proved that mixing sesame paste with carob molasses provided a natural product, characterized by interesting nutritional value (protein: 16.97 g/100 g fry matter, fat: 12.05 g/100 g fry matter and sugar: 9.34 g/100 g fry matter), arising from the constituents of the two ingredients. Thus, the developed blend could offer a promising nutritious and healthy foodstuff to consumers.

Background Proteases are hydrolytic enzymes that catalyze peptide linkage cleavage reactions at the level of proteins and peptides with different degrees of specificity. This group draws the attention of industry. More than one protease in three is a serine protease. Classically, they are active at neutral to alkaline pH. The serine proteases are researched for industrial uses, especially detergents. They are the most commercially available enzyme group in the world market. Overall, fungi produced extracellular proteases, easily separated from mycelium by filtration. Results A new basidiomycete fungus CTM10057, a hyperproducer of a novel protease (10,500 U/mL), was identified as Pleurotus sajor-caju (oyster mushroom). The enzyme, called SPPS, was purified to homogeneity by heat-treatment (80 °C for 20 min) followed by ammonium sulfate precipitation (35–55%)-dialysis, then UNO Q-6 FPLC ion-exchange chromatography and finally HPLC-ZORBAX PSM 300 HPSEC gel filtration chromatography, and submitted to biochemical characterization assays. The molecular mass was estimated to be 65 kDa by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), Native-PAGE, casein-zymography, and size exclusion by HPLC. A high homology with mushroom proteases was displayed by the first 26 amino-acid residues of the NH2-terminal aminoacid sequence. Phenylmethanesulfonyl fluoride (PMSF) and diiodopropyl fluorophosphates (DFP) strongly inhibit SPPS, revealing that it is a member of the serine-proteases family. The pH and temperature optima were 9.5 and 70 °C, respectively. Interestingly, SPPS possesses the most elevated hydrolysis level and catalytic efficiency in comparison with SPTC, Flavourzyme® 500 L, and Thermolysin type X proteases. More remarkably, a high tolerance towards organic solvent tolerance was exhibited by SPPS, together with considerable detergent stability compared to the commercial proteases Thermolysin type X and Flavourzyme® 500 L, respectively. Conclusions This proves the excellent proprieties characterizing SPPS, making it a potential candidate for industrial applications especially detergent formulations.

The hyperlipidemia is a serious health problem that increases the risk of many complications including cardiovascular disease. This study aims to evaluate the possible antihyperlipidemic effects of the feather protein hydrolysate (FPH) in a mice fed with a high‐fat diet (HFD)‐fed mice during 5 weeks. The FPH administration improved dose‐dependent lipid profile, as well as the liver and renal dysfunction indices in hyperlipidemic mice. The FPH also restored the antioxidant status in liver, kidney, and heart by lowering the lipid peroxidation and enhancing the antioxidant enzymes (catalase (CAT), glutathione peroxidase (GPx) and superoxide dismutase [SOD]). Moreover, the histological studies proved that FPH administration prevents hepatic steatosis, glomerular hyperfiltration risk, and cardiac muscle hypertrophy. Accordingly, the FPH is a promising novel medicinal ingredient for possible use in the hyperlipidemic treatment and related complications.

Biological silages were prepared from shrimp head and octopus viscera by-products recuperated from the Tunisian seafood industry. Physical and biochemical changes and microbiological profiles were determined for raw materials during fermentation and on end products. Results showed that biological silage significantly affected (P

1-cm strawberry slices were partially airflow-dried at 50 °C, to reach 0.25 g H2O/g db. Optimized DIC treatment was performed at 350 kPa for 10 s. The final drying stage of these DIC-expanded slices was achieved from 0.25 to 0.1 g H2O/g db (dry basis) using intermittent Pulsed Micro-Wave Drying PMWD to prevent from the paradoxical step of coupled conduction heat transfer with deep generation and transfer of vapor. PMWD was defined at constant 100 W for 3.25±0.05 g with constant active time ton maintained at 2 s, and tempering time toff ranged between 2 and 10 s, or with a continuous way. By decreasing both energy consumption and total drying time of DIC-expanded slices using intermittent microwave, the whole cost significantly decreased to be much lower than the conventional MWD drying, with a great increasing of the quality.Keywords: Airflow Drying; Instant Controlled Pressure-Drop DIC; Swell-Drying; Pulsed Micro-Wave Drying; Physical and Chemical Characteristics.

[EN] The present study aims to find the best drying method to minimize the duration of the operation while respecting the nutritional value of the product. Experiments of convective drying and microwave radiation were respectively carried out with a convective dryer (heat temperature: 65 °C and air velocity: 1.3 m/s) and a microwave oven (power level: 100 W and frequency: 2450 MHz). Six coupling tests between the convective drying and microwave radiation were conducted. The only variable condition is the time output of tomatoes from the convective dryer or the microwave oven corresponding to an intermediate mass ratio (IMR) 0.5, 0.4 and 0.3. The microwave drying removes the bound water faster than convective drying. This explains the observed time savings due to convection-microwave and microwave-convection combined drying. The combination of convection drying and microwave drying to an IMR 0.5 preserved better the red color and the antioxidants of the tomato. Thus, the convection–microwave combined drying (IMR 0.5) proved most suitable for preserving the quality of tomatoes., This study was financed by the National Agency for Energy Control in the context of a Federated Research Project.

The two-phase theory has been frequently used to model fluidised bed drying. At high air velocities, a transition from the bubbling regime to the turbulent regime may occur. In this work, we compare a bubbling model and a turbulent model for the simulation of a two pharmaceutical powders drying in a pilot plant and an industrial plant fluidised bed. The bubbling model was based on a discrete variable bubble size. Heat and mass transfer coefficients were based on the Kunii and Levenspiel correlation [1]. Flow regime was supposed to be completely mixed for the emulsion phase. For the turbulent model, the bubble size is not anymore discrete but continuous and bubble phase is less distinguishable than in the bubbling regime. Heat and mass transfer were those proposed by Foka[2]. In addition, the freeboard section was considered since high entrainment is specific of this regime. Gas backmixing was taken into account by considering a plug flow with axial dispersion for the interstitial gas flow. The bubble phase being dilute, was modeled by a plug flow. A plug flow was also considered for the freeboard gas. The solid phase was supposed to be completely mixed. The bubbling regime simulation gave good agreement with experiment in the case of the pilot plant experiment, while the turbulent model better simulated the industrial scale experiment. Key words: batch fluidized bed, pharmaceutical powder, drying, modeling, bubbling, turbulent

The Municipal Solid Waste of Agareb (Sfax –Tunisia), characterized by high organic fraction and moisture contents is the most worrying pollution source that must be managed by innovative treatment and recycling technologies. Bio-drying, as a waste to energy conversion technology, aims at reducing moisture content of this organic matter. This concept, similar to composting, is accomplished by using the heat generated from the microbial degradation of the waste matrix, while forced aeration is used. The purpose of this work was to reduce the moisture content of the waste, by maximizing drying and minimizing organic matter biodegradation, in order to produce a solid recovered fuel with high calorific value.Keywords: Municipal solid wastes; organic matter; biodrying; composting; energy recovery.

This investigation examines and compares the water sorption isotherms and the thermodynamic properties of two pharmaceutical preparations (Hypril and Azix) intended to be manufactured with the same process plant and equipment. The moisture equilibrium isotherms were determined at 50, 60 and 70 °C using a gravimetric technique. Five isotherm models were explored for their fitting to the experimental data. Azix showed sigmoid type II isotherms while Hypril showed type III isotherms according to the BET classification. All investigated models fitted well the water sorption isotherms of Hypril. By contrast, only GAB and Adam and Shove equations gave appropriate fit to the experimental data of Azix. For both formulations, the isosteric heat and the differential entropy decreased sharply with the increase of equilibrium moisture content to minimum values and thereafter remain constant. In the case of Azix, the integral enthalpy decreased with equilibrium moisture content while the integral entropy increased until reaching a constant value. Contrariwise, Hypril showed decreasing of the integral enthalpy and entropy with the equilibrium moisture content. Keywords: sorption isotherm, enthalpy, entropy, spreading pressure, pharmaceutical formulations

The work was planned to produce dietetic dehydrated strawberries with application of ultrasound osmotic dehydration (UOD) as pretreatment. A Box-Behnken design (BBD) were employed to characterize the UOD strawberry process, optimize and investigate the effect of independent variables like ultrasound time (10, 20 and 30 min), concentration of osmotic solution (distilled water, 32.5 and 65 °Brix) and temperature (20, 30 and 40 °C) on the water loss (WL), solid gain (SG) and weight reduction (WR). The same BBD were used to estimate the main effects of OD without ultrasound treatment. A multi-criteria optimization based on maximal possible values of WL and WR and minimal value of SG was achieved. This was 20.5 min of ultrasound time, 47.5 °Brix osmotic solution concentration and 31 °C medium temperature. The effects of UOD carried out under the optimized operating conditions on kinetics of convective air drying of strawberry at 40, 50 and 60 °C, and velocity of 1 m/s, using the phenomenological model of Coupled Washing/Diffusion (CWD). Starting accessibility, moisture effective diffusivity Deff value and activation energy (Ea) were calculated from similar-Fick’s law and analogous Arrhenius equation, respectively with and without shrinkage correction. Color difference, Chroma and hue angle of fresh and UOD-air dried strawberries were evaluated. Quality attributes were estimated through the assessment of the phenolic content, antioxidant activity, rehydration capacity, and X-ray powder diffraction characteristics.

International audience; A selective supercritical CO(2) extraction process has been developed in order to extract selectively the vegetal oil and the essential oil from coriander seeds in a consecutive way by tuning experimental conditions. A 4-step process has been set up: (i) seeds preparation by grinding and sieving, (ii) extraction by supercritical CO(2) and (iii; iv) selective separation in two separators with different pressure levels. The first part of this study consisted in studying the effects of the operating conditions (T, P, CO(2) density, flow rate and particle size distribution of ground seeds) on the yield of extraction. The results showed that the global performance of the process depends mainly on the pressure level of extraction, on the CO(2) flow rate and on the size of the ground seeds. An optimization of the parameters led to an extraction ratio of 90%. The second part of this study dealt with the effects of the operating conditions on the quality of extracts, and more precisely on their composition in vegetal oil and essential oil. It was observed that the supercritical extraction had no major effect on the fatty acid composition of the vegetal oil compared to classical extraction techniques, while essential oil is enriched in components such as linalool and that a previous drying of the seeds is deleterious. Finally, we propose a procedure in order to extract separately each oil by adjusting CO(2) density and separation conditions. (C) 2011 Elsevier Ltd. All rights reserved.

This paper studies the centrifugal osmotic dehydration (OD), rehydration and texture of carrot tissue treated by pulsed electric field (PEF). The influence of centrifugal acceleration (0–5430g), salt addition (NaCl/sucrose solutions 0/65, 7/44 and 15/50% w/w), and temperature (20–40 °C) on the OD kinetics was investigated in the presence and absence of PEF (E=0.60 kV/cm, treatment duration tPEF=0.05 s). The centrifugal OD of samples untreated and treated by PEF was compared with OD under stirring (250 tr/min). Centrifugal force, PEF and salt addition increase the amount of water removed during OD. However, the centrifugal force decreases the intake of solids by the product. The application of PEF enhances both water loss (WL) and solid gain (SG) during OD (under stirring or centrifugation), increases the rehydration capacity of carrot tissue, but somewhat decreases the firmness of rehydrated product. The combination of centrifugal field with PEF and salt addition can be advantageous for reducing the OD duration. The textural study shows that the product obtained with OD is less affected by thermal treatment than the directly dried product.

The osmotic dehydration mechanism of apple sample pre-treated by pulsed electric field (PEF) was investigated over a range of 44.5–65 ° Brix sucrose concentrations. Apple disks treated by PEF field of 0.90 kV/cm during a constant time t PEF = 0.75 s were immersed in sucrose solution at ambient temperature with 3:1 syrup to apple ratio (w/w). Increase of the initial solute concentration and the PEF treatment resulted in acceleration of the osmotic dehydration (OD). The PEF-treated samples had a higher water loss (WL) and higher solid gain (SG) than the untreated samples. The osmotic dehydration kinetics was studied on the basis of two approaches: Fick's unsteady state diffusion equation and a two-exponential kinetic model. The coefficients of effective diffusion of water and solute were calculated. Their values were higher for samples pre-treated electrically. The effect of PEF was more pronounced for the WL comparatively to the SG. The two-exponential kinetic model permits evaluating of both convective and diffusion stages of OD. The PEF pre-treatment accelerates the kinetics of water and solute transfer during convective and diffusion stages of OD.

The interest of this study is to recover the date's by-products the most common in Tunisia by applying the drying process. The product is getting to be a powder for animal feed. The physicochemical analysis of raw materials showed that dates have a high content of soluble sugars and polysaccharides. The study of dates drying at 50, 60 and 70°C showed that the temperature rises more drying time is reduced. Indeed, dates have initial moisture content of around 0.38kg/kg DM and become stable at the end of drying to moisture content of about 0.15kg/kg DM. The physico-chemical composition of the dates powders at different temperatures show that they are rich in soluble sugars and polysaccharides, high levels of potassium and magnesium and law protein, crude fiber and fat content., L'intérêt de cette étude consiste à valoriser les écarts de triage des dattes (noyau+pulpe) les plus répandus en Tunisie par application du procédé de séchage. Le produit visé est l'obtention d'une farine qui sera destinée à l'alimentation animale. L’analyse physicochimique de la matière première a montré que les écarts de triage des dattes présentent une teneur élevée en sucres solubles et en polysaccharides. L'étude de séchage des dattes à 50, 60 et 70°C a montré que plus la température augmente plus la durée de séchage est réduite. En effet ; les écarts de triage de dattes ont une teneur en eau initiale aux alentours de 0,38 kg/kg MS et deviennent stables à la fin du séchage à une teneur d'humidité de l'ordre de 0,15 kg/kg MS. La composition physico-chimique des poudres de dattes séchées à différentes températures montrent que ces dernières sontriches en sucres solubles et en polysaccharides et ont des teneurs élevés en potassium et en magnésium et présentent des faibles teneurs en protéines, en cellulose brute et en matières grasses.

This work presents a chemical (the minerals, chlorophyll contents and fatty acids) and thermophysical investigation (DSC profile) of four varieties of olive leaves grown in Tunisia. The total chlorophy1l contents of olive leaves ranged from 1132.33 to 1795.93 ppm. The results showed that linolenic acid (C 18:3 ) is the major fatty acid in olive leaves (from 30.02 to 42.16%), followed by oleic acid (C 18:1 ) and palmitic acid (C 16:0 ). The thermal profiles of olive leaf extracts determined by their DSC melting curves revealed simple thermograms with a single peak after melting. The hexane extract of the Chemchali variety, which contained relatively high unsaturated fatty acids and low saturated fatty acid levels, exhibited the lowest peak temperature value (54.59 °C) and required the smallest amount of energy for melting (31.57 J·g −1 ). This study showed that olive leaves possessed physicochemical properties and a fatty acid composition that may become interesting for industrial applications.