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Date and carob syrups are traditional foods produced and consumed in several countries, including Tunisia. Each syrup is characterized by its interesting nutritional and bioactive composition. Several studies have been carried out on the production and characterization of each syrup separately, but this study tends to compare the aromatic, physico-chemical, nutritional and functional properties of commercial carob and date syrups. The results showed a comparable aromatic composition whose major compounds are terpenes (carvone and menthol), a difference in color since carob syrup was characterized by a darker brown color, a nutritional composition rich in sugars and a difference in functional properties since carob syrup had greater emulsifying capacity and antioxidant activity. Thus, the characteristics of carob and date syrups encourage their use in the food industry according to the appropriate product.

The carob tree has several advantages for all its components, especially for its fruits (carob pods). Several scientific studies have shown that the carob fruit is rich in nutrients and phytochemicals, which explains its use as a raw material for the manufacturing of various products, including carob syrup. Some studies have been carried out on the physicochemical characteristics of this product, but to our knowledge, there are no scientific studies yet regarding its functional properties and its potential use in the food industry. So, this work clearly shows that carob syrup has interesting functional properties. It exhibits an emulsifying capacity (~ 80-87%) comparable to that of soy lecithin (~ 100%), an emulsifier widely used in food formulations. This result reveals that carob syrup can be used as a natural food emulsifier for the formation and stability of emulsions.

Le caroubier présente plusieurs intérêts pour toutes ses composantes, surtout pour ses fruits (gousses de caroube ou caroube). Plusieurs recherches scientifiques ont démontré que le fruit de caroube est riche en éléments nutritifs et composés phytochimiques. Ce qui explique son utilisation comme matière première pour la fabrication de divers produits, notamment le sirop de caroube. Certaines études ont été menées sur les caractéristiques physico-chimiques de ce produit, mais à notre connaissance, il n’y a pas encore des études scientifiques concernant ses propriétés fonctionnelles et son utilisation potentielle en industrie alimentaire. Donc, ce travail montre bien que le sirop de caroube possède des propriétés fonctionnelles intéressantes. Il présente une capacité émulsifiante (~80-87 %) comparable à celle de la lécithine de soja (~100 %), un émulsifiant largement utilisé dans les formulations alimentaires. Ce résultat révèle que le sirop de caroube peut être utilisé comme un émulsifiant alimentaire naturel pour la formation et la stabilité des émulsions.

Abstract 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.

Modeling of food moisture content is of interest to correlate experimental data during the storage and packaging to predict the shelf life of the products. An advanced model using statistical physics formalism is used to interpret and discuss the sorption isotherm of water into banana. The desorption isotherms are obtained by the gravimetric static method at three temperatures (35 °C, 50 °C and 70 °C). The fitting allows interpreting the process at microscopic level. A steric interpretation by the mean of the number of molecules per site (n) allows describing the manner of desanchoring from the surface whereas the monolayer quantity Q0 is in relationship with the density of receptor sites NM represents an important parameter for industrial food. An energetic interpretation allows deducing the desorption energy of water during the desorption. By the mean of the statistical model, we calculated the pore size distribution (PSD) the surface of banana. [ABSTRACT FROM AUTHOR]

The by-product generated from carob molasses processing is considered as an excellent source of dietary fiber and may be used as a functional ingredient in food industry. However, it presents a high value of water activity (~ 0.98) which facilitates its microbiological contamination and rapid deterioration. So that, this study provides a solution for the valorization of this by-product and suggests the incorporation of the dried carob by-product into Halva to produce an added value product (Halva with carob powder). Thus, the present work focused on the characterization of carob powder and the optimisation of incorporation percentage of carob powder into Halva formulation. The characterization showed the absence of caffein in carob powder compared to cocoa's one. Besides, carob and cocoa powders had both a brown color. The former had lower fat and higher sugar contents compared to the latter. The optimization promoted the addition of 5% carob powder into Halva formulation according to the evaluation of hardness, sensory quality and exudative stability. Therefore, the new confectionary product could be considered as a promising nutritious and healthy foodstuff to consumers. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

This study aims to investigate the techno‐functional and thermodynamic properties of Cucumis melo peels. Besides, the protein composition of these raw materials was determined showing interesting profile and thus melon peels could be considered as a natural source of essential amino acids for foods formulation. The foam capacity of peel powder was 38.66%. The sorption isotherms were examined at three temperatures 30, 40, and 60°C using the standard static‐gravimetric method. Results illustrated that the water sorption was temperature dependent as typical of food systems. We pursued the research to elucidate sorption isotherms process, which is useful to assess suitable drying and storage conditions of peels. Peleg model was found the best to fit experimental curves for both desorption/adsorption process. The net isosteric heat of sorption and sorption entropy increased with decrease in equilibrium moisture content. Microscopic features throughout peel tissue presented different samples which undergo desorption or adsorption processes. Practical applications: In recent years, a growing interest on the valorization of food processing by‐products has appeared. However, these materials are often prone to microbial spoilage and chemical deterioration, which are directly related to storage conditions as temperature and moisture content of the product. Sorption isotherms are recognized as valuable tools for technologists to predict shelf‐life stability of the products. The principal purpose of the present work was to investigate the techno‐functional properties and thermodynamic features of melon peels. [ABSTRACT FROM AUTHOR]

Instant controlled pressure drop (DIC) was widely used as a treatment to intensify the extraction of bioactive compounds from plants. The aim of this work is to investigate the effect of DIC treatment on the biochemical composition and functional properties of Chemlali olive leaves. DIC conditions were pressure P = 0.1 MPa, number of cycles C = 1 and time t = 11 s. The concentrations of protein, fat, ash, total carbohydrates and fibers in untreated olive leaves powder are 8.62; 3.73; 8.46; 76.49; 64.29 mg/g db, respectively. DIC treatment had significant effects on the chemical composition. Indeed, it increased the amounts of fat (8.33 mg/g db), ash (10.37 mg/g db) and decreased those of protein (6.81 mg/g db), carbohydrates (69 mg/g db) and fibers (53.57 mg/g db). While it had no significant effect on functional properties and pigments. Ten fatty acids were identified and evaluated, with the most abundant being linolenic acid (C18:3) for both olive leaves samples. Mineral analysis proved potassium and calcium as the major elements in both powders. This study showed that DIC treatment is an effective method to increase olive leaves active compounds such as fatty acids and minerals that may be useful in industrial applications. [ABSTRACT FROM AUTHOR]

In this work, a multi objective optimization of batch fluidized drying of two pharmaceutical powders (Group A particles and Group B particles) has been performed using desirability function. Optimization was studied based on non-linear models that take into account particle entrainment and combine dense bed and freeboard sections. Optimization criterion was simultaneously minimizing drying time, dense bed specific energy consumption, and freeboard specific energy consumption. The desired solid final moisture content was considered as a constraint. The control variables were air temperature and air velocity. For the Group B particles, simulation results indicated that desirability increase was monotonic with air temperature increase and air velocity decrease. For the Group A particles, it was shown, the existence of a desirability optimum. By comparing static and dynamic control to the real batch operation, the highest percent reduction of drying time, dense bed specific energy consumption, and freeboard specific energy consumption was obtained for static control with a high value of fixed inlet air temperature. Nevertheless, the risk of product overheating and damaging could be reduced by temperature reduction during the drying process as showed by optimal control trajectories obtained in the case of dynamic control. [ABSTRACT FROM AUTHOR]

The article purpose is to scale-up the bioreactor design for the serine protease from Pleurotus sajor-caju strain CTM 10057 (called SPPS) production to be profitably used in cheese-making production. The SPPS enzyme has been optimized using central composite design (CCD) statistical design analysis. The optimal conditions are: a carbon source of 15 g/L, a nitrogen source of 2 g/L, agitation of 160 rpm at pH = 5.6. This production is scaled-up using submerged fermentation. Under the optimized conditions, protease yield 75,000 U/mL was 6.5 folds higher than those obtained by the use of the initial conditions (11,600 U/mL). The separation was carried out throughout centrifugation followed by a concentration with evaporation, after which this enzyme was tested in the enzymatic milk coagulation process. According to its milk-clotting ability, it could be used in the cheese industry, as well as other food industries. Interestingly, the economic analysis of this planned bioprocess is leased at a positive gain. The estimated SPPS price will be competitive in comparison with commercial enzymes (Mucorpepsine and Presura). So, SPPS enzyme can be used in cheese making and its process is profitable. [ABSTRACT FROM AUTHOR]

A mathematical modeling, based on the two-phase theory of batch fluidized bed drying of type A particles and type B particles pharmaceutical powders, was performed. A perfectly mixed flow bubbling regime and an axially dispersed plug flow turbulent regime with a freeboard section were assumed. The experiments were carried out in a pilot-scale bed and in an industrial scale bed. The experimental sorption isotherms were used to model the falling rate drying period. The influence of the particles hygroscopic properties on the drying rate and on the temperature profile was discussed. The simulated solid moisture content and temperature profiles are in good agreement with the experimental results. [ABSTRACT FROM AUTHOR]

Carob molasses is widely consumed in many Mediterranean countries, including Tunisia where it is known as 'Rub El Kharroub'. The main objective of the present study was to evaluate the physicochemical properties and biological activities of both commercial and homemade Tunisian carob molasses. The physicochemical characterization revealed that the main parameters (color and HMF concentration) were related to non-enzymatic browning reactions occurring during juice concentration. The phytochemical analysis proved that the presence of bioactive compounds (volatile compounds, phenolic substances and products of non-enzymatic browning reactions) in carob molasses samples justify their biological effects (antioxidant and antibacterial activities). Accordingly, such characteristics may qualify Tunisian carob molasses (both homemade and commercial) as nutritious and healthy food that could be directly consumed or used a functional ingredient in food and pharmaceutical industry. [ABSTRACT FROM AUTHOR]

Purpose: The feather is a valuable protein resource. The feather is the major waste by-product resulting from the poultry processing plants. Therefore, increasing the values of poultry feather waste has a significant effect in the environment. Methods: In this study, the physicochemical and functional properties as well as the antioxidant activities of the feather protein hydrolysates (FPHs) obtained by acid hydrolysis after 100 min (FPH100), 200 min (FPH200) and 300 min (FPH300) were investigated. Results: The results showed that FPH100, FPH200 and FPH300 presented high protein content 74.04%, 71.05% and 73.94%, respectively. All FPHs had a good solubility and possessed some interfacial properties, governed by their concentrations. The antioxidant activities of the different FPHs were evaluated using various in vitro antioxidant assays such as 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity, total antioxidant capacity, reducing power and β-carotene bleaching. FPH100 generally showed a greater antioxidant activity across all the considered methods. The DPPH IC50 of FPH100 values were found to be 0.47 ± 0.011 mg/mL. Moreover, the FPH100 exhibited notable total antioxidant capacity and strong reducing power. Conclusions: Our results suggested that FPHs could be a new potential source for preparing natural antioxidants applied in food, pharmaceutical and cosmetic preparations. [ABSTRACT FROM AUTHOR]

The aim of this work is to establish a comparative investigation of the effect of different drying processes: microwave dehydration (100–600 W), air drying (40–60 °C) and infrared drying (40–60 °C) on drying kinetics and on the main quality attributes (color, total phenols and flavonoids contents, water and oil retention capacities) kinetics' of lemon (Citrus limon. v. lunari) peels. The experimental drying kinetics' of lemon peels were fitted to nine thin layer drying models. The Midilli and Kucuk model showed a better fit to experimental drying data for the three drying processes. Microwave drying at 450W preserved the maximum phenols (1.855 ± 0.016 g CAE/100 g DM) and flavonoids (0.802 ± 0.072 g RE/100 g DM) contents respectively. An increase of phenol content was noticed after 9, 13 and 14 min of microwave drying at 600, 450 and 300 W and after 156, 102 and 54 min of infrared drying at 40, 50 and 60 °C. A first-order kinetic model adequately fitted, at the beginning of drying processes, the change of total phenols and flavonoids contents. Total color difference (ΔE) increased progressively with increasing drying time and temperature or microwave power level. ΔE showed a zero-order model whatever the applied drying process. Water retention capacity (WRC) of dried lemon peels decreased during drying processes. However, infrared and microwave drying increased the oil retention capacity (ORC) of lemon peels. The WRC and ORC followed first-order kinetics during air drying and a second order polynomial model during microwave and infrared drying processes. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

BACKGROUND: This study investigated the amino acids, phenolic compounds and volatile compounds in Maazoun melon seeds. The functional properties of melon seed flour, such as bulk density, swelling capacity, emulsifying capacity, and foaming capacity were also determined. RESULTS: The findings proved that the functional properties of melon seeds make them useful for incorporation into different food formulations to improve their functionality. The determination of the amino acid composition of melon seeds showed that glutamic acid (205.23 g kg−1), arginine (130.44 g kg−1), and tryptophan (129.91 g kg−1) were the major amino acids of the protein fraction. Chromatographic analysis indicated that phenolic acids (47.78%) constituted the main phenolic class, followed by flavonoids (27.15%). Naringenin‐7‐O‐glycoside and gallic acid were the most abundant phenolic compounds. Gas chromatography (GC) and gas chromatography–mass spectrometry (GC–MS) analyses of the volatile compounds demonstrated that esters and terpenoids were the main volatile groups. The study of histological structures showed that melon seeds consist of three distinguishable parts: tegument, endosperm cells, and almond. CONCLUSION: The results obtained revealed that melon (Cucumis melo L.) seeds may be a potential source of bioactive compounds and natural substances with nutritive value and functional properties of interest to industrial applications. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

In this work, the effect of Détente Instantanée Contrôlée (DIC) (French for instant controlled pressure drop) on the total polyphenol, flavonoids, α-tocopherol contents, and antioxidant activities of olive leaves was studied. Olive leaf extracts were pre-treated at one cycle DIC under 0.1 MPa pressure for 11 s and followed by an extraction with 95% ethanol at 55 °C during 3 h. The phenolic compounds, flavonoïds, oleuropein, and α-tocopherol contents were determined, showing 66.63 mg gallic acid equivalent (GAE)/g db, 12 mg catechin equivalent (CE)/g db, 43.9 mg/g db, and 0.15 mg/g db for the untreated leaves against 239.37 mg GAE/g db, 28 mg CE/g db, 70.3 mg/g db, and 0.59 mg/g db for DIC-treated leaves, respectively. Therefore, DIC allows more availability of bioactive compounds contributing to a high antiradical activity (DPPH) compared to a synthetic antioxidant butylated hydroxytoluene (BHT). Both extracts showed a total antioxidant capacity (method of phosphomolybdenum) greater than that of the standard BHT. Likewise, both extracts have a reducing power (FRAP test) significant concentration-dependent. The DIC-treated leaves showed a higher antioxidant capacity compared to that of untreated leaves. Thus, DIC could be an effective treatment to promote the extraction of bioactive molecules of high antioxidant activities from olive leaves. [ABSTRACT FROM AUTHOR]

This study was aimed at the determination of bovine leather moisture sorption characteristics using a static gravimetric method at 30, 40, 50, 60 and 70 °C. The curves exhibit type II behaviour according to the BET classification. The sorption isotherms fitting by seven equations shows that GAB model is able to reproduce the equilibrium moisture content evolution with water activity for moisture range varying from 0.02 to 0.83 kg/kg d.b (0.9898 < R2 < 0.999). The sorption isotherms exhibit hysteresis effect. Additionally, sorption isotherms data were used to determine the thermodynamic properties such as isosteric heat of sorption, sorption entropy, spreading pressure, net integral enthalpy and entropy. Net isosteric heat of sorption and differential entropy were evaluated through direct use of moisture isotherms by applying the Clausius-Clapeyron equation and used to investigate the enthalpy-entropy compensation theory. Both sorption enthalpy and entropy for desorption increase to a maximum with increasing moisture content, and then decrease sharply with rising moisture content. Adsorption enthalpy decreases with increasing moisture content. Whereas, adsorption entropy increases smoothly with increasing moisture content to a maximum of 6.29 J/K.mol. Spreading pressure increases with rising water activity. The net integral enthalpy seemed to decrease and then increase to become asymptotic. The net integral entropy decreased with moisture content increase. [ABSTRACT FROM AUTHOR]

This paper aims to promote the artificial ripening of Algeria's dry Deglet-Nour dates commonly named Frezza, by successive treatments using hot water soaking and hot vapor steaming. The main objective of the study was to optimize the gain in mass during the proposed hydrothermal process using an experimental design method. Water uptake during rehydration has been optimized according to two complete factorial designs; the first 23 based on eight experiments and the second 22 of four experiments. The conducted experimental investigations showed a maximum of water gain by water soaking and a little part by steaming operation. Obtained and analyzed results led to optimal conditions defined by soaking in water at 30 °C during 8 h followed by hot vapor treatment in a confined chamber at 60 °C under 90% RH. Practical Applications Artificial ripening of Deglet-Nour dates, with different hydration techniques, is an industry practice known in Algeria since the 1950s, but under nonoptimized operating conditions. This paper presents a contribution to the optimization of the rehydration process of dates by water soaking and hot vapor steaming. The results of the study will be useful in the sense of ensuring an added value by enhancing the product quality. The obtained results also permit to minimize the necessary energetic consumption for steam production. [ABSTRACT FROM AUTHOR]

The aim of this work was to determine the effect of air drying temperature (40 °C, 50 °C, and 60 °C) on the degradation kinetics of quality parameters of lemon peels. Drying at 40 °C was in favor of maximal water and oil retention capacities and lowest color loss (35%), but it also induced lower phenolic and flavonoids residual contents. First-order reaction model showed a good fit for lightness and yellowness color parameter. Zero-order reaction model fitted well redness color parameter and total color difference. A higher value of activation energy indicated greater heat sensitivity of lightness and redness during air drying. [ABSTRACT FROM PUBLISHER]

Moisture sorption isotherms of apples and pears were determined at 30, 45, and 60°C and water activity (a w ) range of 0.04–0.83 using a standard static gravimetric method. The sorption isotherms of both fruits decreased with increasing temperature and exhibited type III behavior according to Brunauer–Emmett–Teller (BET) classification. The moisture desorption data fitted well with the Peleg model (0.997 ≤ r ≤ 0.999, 0.009 ≤ SE ≤ 0.071, and 4.840 ≤ p ≤ 13.779). The glass transition temperature (T g ) of both fruits decreased linearly with the increase in water activity (a w ). The variation in glass transition temperature versus water activity (T g  ∼ a w ) and glass transition temperature versus solid fraction of pears and apples (T g  ∼ W s ) were adequately predicted by Khalloufi et al.'s model (0.998 ≤ r ≤ 0.999 and 0.007 ≤ SE ≤ 4.088) and the Gordon and Taylor model (0.879 ≤ r ≤ 0.979 and 9.798 ≤ SE ≤ 18.507). The thermal transition and desorption isotherms data were used to establish state diagrams of pear and apple and evaluate suitable fruits storage conditions. [ABSTRACT FROM AUTHOR]

The aims of this work were to determine the desorption isotherms of “Maltaise" orange peel and leaves and to investigate the effect of the infrared drying on the drying kinetics and on the physical and functional properties. The moisture desorption curves showed a sigmoïd shape (type II on the BET classification). GAB was found to be the best model for describing the desorption curves. The infrared drying rate increased, with temperature increasing at the same moisture ratio. High drying temperatures preserved initial color parameter values of “Maltaise” orange peels (from 21.893 ± 0.629 to 24.793 ± 0.525, from 37.973 ± 0.941 to 45.44 ± 0.390 and from 45.350 ± 1.077 to 50.439 ± 0.740 for a*, b* and C, respectively) and leaves (from -5.98 ± 1.651 to -5.276 ± 0.342, from 10.73 ± 1.547 to 16.42 ± 0.174 and from 12.283 ± 2.263 to 17.247 ± 0.384 for a*, b* and C, respectively) and maximal phenolic content. Nevertheless, water and oil holding capacities decreased significantly. Low temperatures gave the best functional properties. [ABSTRACT FROM AUTHOR]

By 1976, chemical and mechanical engineering had produced a tremendous effort to understand drying in physical terms, mainly for consolidated bodies. In spite of an obvious interest aroused by the food processing industry, very little had been done on saturated deformable media. This article relates how a succession of nineteen Ph.D. students tried to enforce into practical and fundamental drying the relatively few laws we have at our disposal in continuum mechanics. Practical problems suggested by industry alternated with more theoretical work in an unplanned manner: it was my duty and my pleasure to ensure that all treatments echoed correctly with a certain harmony. [ABSTRACT FROM AUTHOR]

The osmotic dehydration (OD) of food plant tissue constitutes an alternative step for drying. As OD is relatively slow, pulsed electric field (PEF) can be used to accelerate this process. The application of PEF induces a cell membrane permeabilisation with formation of pores accelerating the solute and water transport through the cell membrane. In this study, apple samples were subjected to a PFF pre-treatment, followed In an immersion in an osmotic solution at 25 C containing 44.5 w/w of sucrose, The impact of pre-treatment conditions (electric held intensity, pulse number) on the concentration of osmotic solution ( Brix), the water removal and the solid content in apple samples were studied. Compared to untreated apples. the application oh' the PEF pre-treatment resulted in decrease of sugar concentration in the osmotic solution and higher solid content in apple samples. The variation of electric field conditions showed that the optimum PEF parameters were 0.90 kV/cm and 750 pulses with a pulse duration of 100 μs, which corresponds to an energy input of 13.5 kJ/kg. A continuous method was developed to follow the evolution of OD kinetics on the apple tissue, Experiments were fitted by a two-exponential model describing the kinetics of water and solute transfer during the OD. This enables the determination 01 mass transfer coefficients demonstrating that PEI increased both the convection and diffusion rates. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

This work focused on studying the drying kinetics of sesame coat at different microwave drying levels (100, 180, 450, 700, and 850 W) and investigating its effect on physico‐chemical and functional properties. Results showed that the drying time was significantly affected by microwave power level. In fact, it decreased from 14 min at 100 W to 2 min at 850 W. Raw sesame coat, as an industrial by‐product, is characterized by a high water activity value (0.98) and fiber content (47.91 ± 3.60 g/100 g dry basis). The microwave drying had reduced significantly (p < .05) water activity to about 0.5. ANOVA test indicated that increasing microwave power level had no significant (p > .05) effect on both total phenol content and browning index. However, it had improved the functional properties (water and oil holding capacities). Practical application: The by‐products of sesame seed (Sesamum indicum L.) processing industries are considered as an excellent source of dietary fiber and may be used as a functional ingredient in food industry. This work evaluated the impact of microwave drying, as a new trend, on sesame coats' quality. Experimental results showed that microwave application had a shorter processing time and it enhanced the quality of final products. [ABSTRACT FROM AUTHOR]