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In this study, films based on two different polysaccharides (chitosan and cassava starch) were produced by casting technique and nanostructured by montmorillonite (MMTNPs) or bamboo nanofibers (BNFs) at two different concentrations: 0.5 g/100 g and 1.0 g/100 g of polymer, using glycerol as plasticizer at concentration of 30 g/100 g of polymer. The particle size and surface charge of the MMTNPs and BNFs nanoparticles were 315 ± 14 nm and 60 ± 3 nm and −31.78 mV and −20.77 mV, respectively. In relation to the mechanical properties, the nanofibers increased the tensile strength in 50% of starch films, while the elongation at break shows a similar increase (66%) for both types of nanoparticles at concentration of 1.0 g/100 g. Cassava starch films showed a better response to nanostructure process, noticed through by the mechanical properties. XRD analyses showed good interaction between the polymer matrix and bamboo nanofibers. [ABSTRACT FROM AUTHOR]

In this research the application of ultrasound, prior to air-drying, describing the phenomena in two approaches: unripe banana slices immersed in water (hydrated) and vacuum packaged (non-hydrated) were investigated. The results showed two falling rate periods during the air-drying. For the second rate period, an increase of water effective diffusivity due to the "sponge effect" (direct effect of ultrasound) and the microscopic channels formation (indirect effect) was observed. Scanning electron microscopy images showed that untreated dried slices were less porous, characterized by small cavities and high density, while ultrasound pretreated slices resulted in a porous structure with more free volume between cells. An increase in porosity decreased the resistance for diffusion, influencing positively the water effective diffusivity. Moreover, ultrasound produced partial disorder of the crystalline structure within the starch granules, reducing the amount of energy required for gelatinization. Moreover, reduction of resistant starch content was not observed. [ABSTRACT FROM AUTHOR]

The rheological behavior of banana puree was determined using a dynamic stress rheometer with a pressure couette fixture, which allowed experiments to be conducted at high temperature. The pressure couette was pressurized with compressed air to 206.8 kPa (gage pressure) and experiments were carried out at temperatures ranging from 30 to 120°C. The shear stress values ranged from 10 to 170 Pa and the shear rate values from 10-5 to 103s-1. The model that best fitted the experimental data at all temperatures was the Herschel-Bulkley model. There was a usual tendency for the apparent viscosity to decrease with increasing temperature but an increase in apparent viscosity with increasing from 50 to 60°C and from 110 to 120°C was found. This could be due to interaction of polysaccharides present in banana puree. There was a slight difference between the apparent viscosity values for increasing shear stress sweeps and those for the decreasing shear stress sweeps suggesting time dependency of the rheological were shown to meet these requirements. Their inclusion either individually or in combinations in `high risk" products such as salad dressings and sandwiches should be considered. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the effect of multiple wavelengths of UV-C light sources on the inactivation of polyphenol oxidase (PPO) and peroxidase (POD) in buffer solutions. Enzyme solutions were treated with a UV-C excimer lamp (EL) emitting at 222 nm, low-pressure mercury (LPM) lamp at 253.7 nm, four UV-LEDs sources emitting at 255, 265, 275 and 285 nm, and a novel pulsed UV-C lamp (PL) emitting at 232, 242, 261 and 272 nm. Three kinetic models were used to compare UV-C wavelengths enzymatic inactivation efficacy considering the volume average fluence for 90% reduction (H D). Validation of kinetic parameters was performed under continuous-flow treatment in a UV-C LED and EL system. EL treatment resulted in the highest inactivation efficacy of PPO and POD enzymes with H D of 52.8 and 74.8 mJ/cm2, respectively. PL inactivation efficacy for both enzymes was higher than with LPM lamp or UV-LEDs. The two-component first-order model best described the inactivation of PPO and POD in a buffer solution. The adjusted kinetic parameters for this model were validated under UV-C light continuous flow processing. This study contributes to the development of liquid food treatment by ultraviolet technology. • Compared the feasibility of several UV-C light sources on enzymatic inactivation. • 90% inactivation was achieved for all wavelengths tested and fluence was established. • Kinetic model to represent UV-C enzymatic inactivation was adjusted and validated. • Excimer lamp at 222 nm showed greater inactivation efficacy than UV-C LEDs and LPM lamp. • POD showed to be more UV resistant than PPO. [ABSTRACT FROM AUTHOR]

In this study, biodegradable films were produced from cassava starch modified by ozone at different levels. The films were produced by casting technique using native and ozonated cassava starch, glycerol as the plasticizer, and water as the solvent. Films were characterized in term of their mechanical, barrier and functional properties, morphology, crystallinity, colour, and opacity. The morphology of the ozonated films was more homogeneous in comparison to the films produced with the non-modified starch and enhanced properties were achieved. Films produced with ozonated cassava starch presented higher tensile strength, Young's modulus and lower elongation. The water vapour permeation and the oxygen permeation were increased by increasing the ozonation time. Moreover, ozone processing resulted in films with a more hydrophilic surface and lower solubility after 24 h. Possible explanations and applications were discussed. In conclusion, the ozone processing showed to be a good alternative for starch based packaging production. • Ozone processing change both starch molecules size and charge. • Ozonation resulted in film with enhanced mechanical properties. • A good alternative for packaging was developed. [ABSTRACT FROM AUTHOR]

The dielectric properties of three different reconstituted infant formulae, human milk, as well as, whole and low-fat pasteurized cow milk were measured at temperature interval from (5 to 70) °C and at frequency of 2450 MHz. The dependency of the dielectric properties with temperature is presented. The values of penetration depth were determined and can be used to estimate the ideal bottle-feeding or container diameter to use in a domestic microwave oven or specific microwave equipment to pasteurize human milk in Human Milk Banks (HMB). [ABSTRACT FROM AUTHOR]

Abstract The enzyme pectin methyl esterase (PME) kinetic inactivation study in orange juice was performed by conventional heat treatment (thermal bath) and focused microwave heating (synthesis microwave reactor). Experiments have been performed in batch, with temperatures ranging between 50 °C and 95 °C for time between 0 and 60 s for both processes. Non-isothermal processes were considered and histories of time-temperature have been acquired. The kinetic model adjusted considered two fractions of PME (thermosensitive and thermoresistant), and the kinetic parameters to microwave processes at T ref = 90 °C were z 1 = 13.7 °C, z 2 = 20.3 °C, D 1 = 0.231 s and D 2 = 130.8 s with α = 0.95. Comparative analysis of processes was performed graphically by residual enzymatic activity versus lethality. The results demonstrated the microwave-assisted thermal process was more effective than conventional one under the same conditions, indicating the possibility for some additive non-thermal effects. Innovative conditions of inactivation were achieved: i.e. 90% at 60 °C after 10 s and 99% at 80 °C after 20 s. Highlights • Kinetic of inactivation considering non-isothermal conditions. • Focused microwave system to orange juice pasteurization. • There were possible some additive non-thermal effects from microwave. [ABSTRACT FROM AUTHOR]

The effect of three enzymes on the fundamental rheological parameters of bread dough with high content of resistant starch (RS) was studied. The RS was added as an alternative to increase the fiber ingestion while the enzymes, to overcome the gluten dilution. Optimum dough was formulated with partial substitution of wheat flour by RS (12.5 g/100 g) and enzymes transglutaminase (4 mg/100 g), glucose oxidase (2.5 mg/100 g) and xylanase (0.5 mg/100 g). Dough produced with RS and without enzymes was considered as control and dough without RS or enzymes was considered as regular for comparison. Fundamental rheological parameters were obtained from uniaxial extension, biaxial extension and oscillatory tests. Also, starch gelatinization and retrogradation were studied by differential scanning calorimetry. The partial replacement of WF by RS resulted in less extensible dough, whereas the addition of enzymes increased the strain hardening index allowing higher dough expansion. The addition of enzymes reduced the elastic modulus resulting in a behavior similar to the regular dough. RS was not gelatinized during baking, hence it can be considered as dietetic fiber. Wheat starch retrogradation after 7 days of storage was observed, indicating bread aging. [ABSTRACT FROM AUTHOR]

Thermophysical properties and hygroscopic behavior of unripe banana ( Musa cavendishii ) were studied. The sorption isotherms were measured at 25 °C, 40 °C, 50 °C and 60 °C and the observed sigmoid curves were modeled with GAB equation which satisfactorily fitted the experimental data. The mean value of monolayer moisture content ( X m ) estimated was (5.5 ± 0.6) g/100 g d.b. Drying experiments were conducted at temperatures of 40 °C, 50 °C and 60 °C and the apparent density, specific heat, thermal conductivity and thermal diffusivity – were directly measured as a function of moisture content and porosity. Empirical models obtained by nonlinear regression were successfully fitted to the thermophysical properties, important data to model and simulate the drying process. [ABSTRACT FROM AUTHOR]

The effect of three enzymes on the rheology and the baking performance of bread dough with high content of resistant starch (RS) was studied. The RS was added as an alternative to increase the fiber ingestion while the enzymes, to make up the gluten dilution. A full factorial 2 3 design with central point in triplicate was applied with dough formulated with partial substitution of wheat flour by RS (12.5 g/100 g) and the enzymes: transglutaminase (0–8 mg/100 g), glucose-oxidase (0–5 mg/100 g) and xylanase (0–1 mg/100 g). Dough produced without RS or enzymes was considered as regular and dough produced with RS and without enzymes was considered as control for comparison. Bread was produced from regular, control and optimum formulations and the quality was assessed concerning specific volume, firmness and preference by sensory panel. Enzymes had significant effect ( p < 0.05) on the weakening coefficient obtained by fermentation monitoring indicating the central point as optimum formulation. From bread quality tests it was observed that the RS delayed, whereas the enzymes accelerated the aging process. No significant difference of attribute preference was detected by sensory panel, while the bread produced with the optimum dough had the highest value. [ABSTRACT FROM AUTHOR]

Dielectric properties (relative permittivity ɛ ′ and loss factor ɛ ″) are key parameters for microwave heating of food products. In view of continuous microwave processing of green coconut water (GCW), dielectric properties and electric conductivity were determined by open-ended coaxial probe technique at temperatures between 0 and 90 °C and frequencies between 500 and 3000 MHz. Simulated solutions of salts and sugars from GCW were also tested to evaluate component contributions and interactions. At 915 MHz, ionic conduction plays an important role in microwave heating, while a balance between ionic and dipolar mechanisms was observed at 2450 MHz, depending on temperature. Sugars had a weak effect on polarization or loss. Component interaction reduced ɛ ″ (approximately 12% at 915 MHz and 8% at 2450 MHz). It was possible to follow the change of the dielectric properties and the power penetration depth as the temperature raised and correlations were adjusted to model temperature dependence. [ABSTRACT FROM AUTHOR]

[Display omitted] • An exploratory routine was carried out for a novel NSP-rich ingredient. • Interactions with water and exposure to high and low temperatures were studied. • Sorption isotherms of ripe bananas non-starch polysaccharides samples were Type III. • State diagrams of non-starch polysaccharides NSP from ripe bananas were built. • The stability criterion between water activity and glass transition was studied. In this work, an ingredient containing non-starch polysaccharides (NSP), obtained from overripe bananas, was characterized using differential scanning calorimetry (DSC) and vapor sorption isotherms. Soluble sugars from overripe bananas were extracted using ethanol, resulting in a solid NSP-rich fraction. The physical properties of this new ingredient and its response to temperature and water interactions are needed for its application as a fiber flour aggregate in food preparations. Results from thermal analyses, including gelatinization, glass transition and fusion, allowed building state diagrams, then compared to vapor sorption isotherms which resulted similar to a Brunauer–Emmet–Teller (BET) type III isotherm at 25 °C, for NSP and standards samples as arabinoxylan and polygalacturonic acid. A good fit was obtained for the glass transition curves using the Kwei model. This approach enabled us to explore the stability of the material, regarding safety limits for microbial deterioration and structural changes due to glass transition. [ABSTRACT FROM AUTHOR]

In this research, the effect of montmorillonite nanoparticles (Mt) filling polymer blends (PB) of starch/chitosan at concentrations of (0.5 and 1.0) g of Mt/100 g of PB was investigated. The Mt was dispersed at a rotational frequency of 2500 rpm in a cold bath at 0 °C, allowing to obtain nanoparticles with an average size of (315 ± 14) nm. On the one hand, the films presented an increase of 72.4% in the tensile strength as a function of the increase in the concentration of chitosan. Consequently, the composites showed an increase of 85.6% due to the increase in chitosan and the Mt presence. In addition, the composites had an improvement of 33.7% in the water vapor barrier explained by the lower permeability index in function to the higher clay nanoparticle concentration. On another hand, the yellowness characteristic color was evident with the increase of chitosan concentration. The biodegradable PB: Mt films produced in this research have a high potential for industrial application and can be used as food package materials. [ABSTRACT FROM AUTHOR]

Abstract: For the optimal design of plate heat exchangers (PHEs), an accurate thermal–hydraulic model that takes into account the effect of the flow arrangement on the heat load and pressure drop is necessary. In the present study, the effect of the flow arrangement on the pressure drop of a PHE is investigated. Thirty two different arrangements were experimentally tested using a laboratory scale PHE with flat plates. The experimental data was used for (a) determination of an empirical correlation for the effect of the number of passes and number of flow channels per pass on the pressure drop; (b) validation of a friction factor model through parameter estimation; and (c) comparison with the simulation results obtained with a CFD (computational fluid dynamics) model of the PHE. All three approaches resulted in a good agreement between experimental and predicted values of pressure drop. Moreover, the CFD model is used for evaluating the flow maldistribution in a PHE with two channels per pass. [Copyright &y& Elsevier]

The influence of polydextrose or plant proteins blend, as a drying aid in freeze-dried açaí pulp, was evaluated regarding stability by vapor sorption isotherms at 20 °C in a water activity range of 0.1–0.95, obtained by vapor sorption analyzer and by saturated salt solutions, and the enthalpic properties were obtained by differential scanning calorimetry. The experimental isotherms data presented a good fit to the Peleg and Guggenheim-Anderson-de Boer (GAB) equations, açaí powder with polydextrose presented a Brunauer-Emmett-Teller (BET) type III, while the açaí powder without and with a plant proteins blend, type II. The freeze-dried açaí powders showed two endothermic peaks between −15 °C and 10 °C, probably related to linoleic and oleic fatty acids fusion. Fusion enthalpies of these peaks were lower when a carrier agent was used, which could be explained by a lower lipids content (25.0 J/g and 3.5 J/g for powder without the carrier and 12.0 J/g and 1.5 J/g for powder with plant proteins blend). The glass transition temperatures were between 49 °C and 58 °C, depending on the water activity, for powder without carriers and from 45 °C to 54 °C for the one with proteins. • The glass transition temperature between 49 °C and 58 °C for açaí powder without carriers. • The glass transition temperature between 45 °C and 54 °C for açaí powder with plant proteins blend. • Polydextrose as a drying aid reduced glass transition temperature with water activity increased. • Adsorption isotherms of freeze-dried açaí with polydextrose were BET type III. • Adsorption isotherms of freeze-dried açaí with plant protein blend was BET type II. [ABSTRACT FROM AUTHOR]

This study aimed to produce sustainable smart packaging based on cassava starch and a natural pH indicator (anthocyanin) by a twin-screw extrusion process. It also aimed to evaluate various anthocyanin concentrations (5, 10, 20) mg ATH per 100 g on selected sheet properties and the indication of pH changes. The incorporation of ATH generated sheets thicker (~2.5x), less resistant at break (~4.5x), less flexible (~1.4x) and less rigid (~4.5x). However, ATH did not affect the crystallinity profile. The thermoplastic starch sheets incorporated with 20 mg ATH/100 g showed the best behavior as a smart packing indicator of pH change in meat stored at 6 °C, with the higher variation of Δ E * and the most visually notable color change. Therefore, this work allowed producing sustainable smart packing by the large-scale method (extrusion), and it can expand the application of this type of material in the food industry. Image 1 • Smart packaging based on cassava starch and anthocyanin was developed by extrusion. • The increase of anthocyanin content resulted in sheets more colored. • Anthocyanin affected negatively, mainly, the mechanical properties of the sheets. • Sheets incorporated with anthocyanin showed the capacity to be a pH change indicator. • Sheets with highest anthocyanin concentration presented the best pH changing indication. [ABSTRACT FROM AUTHOR]

The influence of temperature, frequency, composition and physicochemical characteristics of sheep milk on its dielectric properties was evaluated as well as the performance of different chemometric methods to predict the dielectric properties and classify the type of sheep milk (whole, semi-skimmed and skimmed). Of the chemometric methods evaluated, artificial neural network exhibited the best performance for prediction of the dielectric properties, while sensitivity analysis showed temperature, electrical conductivity, and fat and calcium content as variables with the most impact. All pattern recognition techniques showed 100% for recognition and prediction ability to classify correctly the type of milk. Although the approach used in this study is limited to the specific operating conditions and sheep milk studied, chemometric methods have proven to be promising tools because of accuracy and suitability for both prediction of the dielectric properties of sheep milk and monitoring quality control parameters of milk and dairy products. [ABSTRACT FROM AUTHOR]

Unripe acerola powders obtained from freeze-drying without (AV) and with polydextrose (AP) were characterized by using differential scanning calorimetry (DSC) and vapor sorption isotherms at (25, 35, and 45) °C in water activity (a w) range of 0.10–0.90. State diagrams built from DSC results, such as the glass transition (T g) and freezing (T m) points, were compared with those of the sorption isotherms. The Gordon-Taylor equation presented a good fit for T g , in which the solids glass transition increased and the k parameter decreased in the presence of polydextrose. The isotherms obtained were Brunauer-Emmett-Teller (BET) type III, and the Guggenheim-Anderson-de Boer (GAB) equation fitted to the experimental data showed slightly higher monolayer water content for AP, and not affected by temperature. Although there was a divergence in the stability when comparing the criteria of a w and T g , polydextrose increased the a w and T g of freeze-dried unripe acerola and conferred a stabler powder. • The stability criterion between water activity and glass transition was studied. • State diagrams of unripe acerola with polydextrose were built. • Polydextrose used as a drying aid increased the glass transition temperature. • Sorption isotherms of unripe acerola powders were BET Type III. [ABSTRACT FROM AUTHOR]

This work investigates the drying of yacón (Smallanthus sonchifolius), a source of fructooligosaccharides and inulin, two prebiotic compounds. Experiments were performed using an in-house device consisting of a magnetic suspension balance coupled to a drying chamber and an in-situ shadowgraphy system. This allowed the continuous acquisition of mass, sample volume and exchange surface area to be register versus time at different temperatures (50–70 °C) and relative humidities (10%–30%), which was never done with yacón. Once corrected by the actual area of the exchange surface, the drying kinetics (kg. s − 1 . m − 2 ) depicts two phases, a very long constant drying rate flux and a falling drying rate flux. Even though yacón samples lost up to 91% of their initial volume, an iso-volume deformation was observed: the reduction of sample volume equals the volume of removed water. Thanks to these two experimental facts, an extended, original, van Meel model is proposed to account for this huge change of sample shape in a predictive way. • Convective drying of yacón performed with an original device at controlled conditions. • The actual shape of the sample monitored continuously by digital image correlation. • Iso-volume deformation is evidenced: volume change equals volume of removed water. • The anisotropy ratio is explained by the anatomical structure, as observed by ESEM. • An extended van Meel model is proposed to account for large iso-volume deformation. [ABSTRACT FROM AUTHOR]

In this work, a methodology to measure torque during dough mixing in large scale was developed and the baking performance of bread dough formulated with resistant starch (RS) and enzymes was evaluated. Dough was formulated with 12.5 g/100 g of RS and 4 mg/100 g of a mixture of enzymes, glucose-oxidase (Gox), tranglutaminase (TG) and xylanase (HE) in proportions according to a three-component mixture design of experiments. Dough was mixed in a large-scale dynamic rheometer measuring instant torque and speed in real time through a personal computer (PC) interface. Maximum torque during mixing and parameters of the dough development curves obtained from rheofermentometer were fit to mathematical models within 95 % of confidence. Gox and TG showed positive effects on the maximum height of dough, while HE showed a negative one. Also, it was found that Gox and TG in the presence of HE could be important for reducing dough weakening. [ABSTRACT FROM AUTHOR]

The intake of unavailable carbohydrates—functional ingredients—has presented an inverse relationship with the risk for non-communicable diseases. Inulin and unripe banana flour (UBF) (source of resistant starch—55%) are among these ingredients. The aim of this work was to evaluate the impact of regular and discontinued intake of inulin or UBF on the plasma levels of gastrointestinal hormones and energy intake in healthy volunteers. A medium-term clinical assay was conducted with healthy volunteers, both males and females (n = 33), who were oriented to consume soup with added inulin (INU group), UBF (UBF group) or maltodextrin (Control group) three times a week for six weeks. Prototypes of two different types of frozen soups were provided by a food industry. The plasma concentration of satiety-related gastrointestinal hormones was evaluated before and at the end of the intervention. Blood collection was performed 180 min after the consumption of breakfast ad libitum. The energy intake was evaluated at the subsequent meal (180 min). UBF consumption (8 g) caused significant changes in the plasmatic levels of the gastrointestinal hormones when compared to the period before the intervention: there was a lower increase in ghrelin (T0, T60, T120 and T180 min) and a decrease in insulin (T0 and T180 min), hormones related to hunger, when at high levels, as well as an increase in peptide YY (PYY) at all timepoints. When comparing the Control and UBF groups at the end of the intervention, the latter presented a reduction in ghrelin (T0, 120 and 180 min) and insulin (T0 and 180 min) and an increase in PYY (T30 and 180 min). The consumption of inulin (8 g), compared to the period before and at the end of the intervention, resulted in a lower increase in ghrelin (T0, T120 and T180 min) and a decrease in insulin (T180 min). PYY also increased at all timepoints, which indicates higher satiety. When the Control and INU groups were compared at the end of the intervention, the INU group presented reductions in ghrelin (T0, 120 and 180 min) and insulin (T180 min) and an increase in PYY (T180 min). At the subsequent meal, there was a reduction in energy intake of approximately 15% (129 kJ) for the UBF and 12% (130 kJ) for the INU groups. Both inulin and UBF present positive effects on gastrointestinal hormones and energy intake and may be used for producing products that stimulate healthy eating habits. [ABSTRACT FROM AUTHOR]

The green banana flour (GBF) from Musa cavendischii , variety “Nanicão”, can be used as a functional ingredient due its high content of resistant starch (RS 2 ), in view of postprandial glycemic reduction and insulinemic levels when ingested. However, the GBF presents a cohesive profile, a low rate of wettability and dispersability in water at ambient temperature, besides its RS is thermo sensitive. Therefore, GBF was submitted to an agglomeration process using a pulsed fluidized bed (PFB) at pulsation frequency of 10 Hz. Aqueous solution of sodium alginate (5 g/100 g) was used as binder at a flow rate of 3.0 mL min −1 , and temperature of 95 °C, pressure of 100 kPa, air velocity of 1.2 m s −1 and time of 50 min. Agglomerated flour was obtained with reduced moisture content, increased mean particle diameter, high flowability and porosity with irregular shape. Agglomerated flour presented a RS content of (53.95 ± 0.22) g/100 g in comparison to (57.49 ± 0.43) g/100 g (db) to the original content, showing that the agglomeration process did not affect the functional properties of GBF and increased the particles wettability properly to be used in liquid preparations. [ABSTRACT FROM AUTHOR]

Low-Temperature Long-Time pasteurization (LTLT) is normally applied in donor human milk from Human Milk Banks (HMBs) to guarantee microbiological safety; however, this treatment can modify the protein structures, decreasing their beneficial effects. Thus, this study aimed to determine the impact of microwave-assisted heating on the concentration of key biological compounds in donor human milk to verify whether a microwave heating technique can be used as an alternative to LTLT pasteurization in Human Milk Banks. The concentrations of oligosaccharides, immunoglobulins, lactoferrin and fatty acids were monitored in raw donor milk and after processing to assess the impact of the microwave and LTLT treatments. The concentration of oligosaccharides was determined by HPAEC-PAD, immunoglobulins and lactoferrin were quantified using ELISA kits and fatty acids were quantified by gas chromatography. Oligosaccharides and fatty acids were not significantly affected (p > 0.05) by LTLT and microwave processes; however, immunoglobulins and lactoferrin concentrations were better preserved when microwave-assisted heating was applied. For this reason, microwave-assisted heating can be considered a promising alternative to LTLT pasteurization of donor human milk in Human Milk Banks. • Oligosaccharides and fatty acids were not affected by LTLT and microwave processes. • Immunoglobulins and lactoferrin were better preserved with microwave heating. • Microwave-assisted heating is an alternative to pasteurize donor human milk. [ABSTRACT FROM AUTHOR]

The objectives of this research were to study the effect of the addition of lyophilised kefir milk to premixes for household production of bread and evaluate the quality attributes of them. Four lyophilised samples were obtained from the followings: skim milk, acidified skim milk, fermented skim milk and neutralised fermented skim milk. Breads were prepared with commercial wheat flour, lyophilised milk samples and yeast through a straight dough process. Quality was assessed through loaf volume, crumb porosity and moisture, crumb texture and crust colour. Changes in texture and starch recrystallisation by X-ray diffractometry were determined after 1 and 3 days of storage at room temperature. Breads with acidified milks showed the highest specific volumes and crumbs with the best texture properties. Crystallinity in bread with fermented milks was higher than for skim milk sample. This would indicate that there would be a certain effect of the type of milk processing on the promotion of starch retrogradation. [ABSTRACT FROM AUTHOR]

Highlights: [•] Development of biodegradable films impregnated with cinnamaldehyde. [•] Supercritical solvent impregnation (SSI) was used to produce active films. [•] Total amount of impregnated cinnamaldehyde depends on CO2 solubility. [•] Water vapor permeability of the films decreased after SSI. [ABSTRACT FROM AUTHOR]

Although the number of studies focused on bio-based plastics is constantly rising, an important challenge to overcome is migrating from casting to extrusion, an industrially scalable method of production. In this work, we studied starch modification by dry heating treatment (DHT) and the production of cassava starch films or sheets, by casting or extrusion processes, respectively. The molecular changes promoted by the DHT process resulted in a new matrix. Furthermore, the slower drying in casting, and the faster drying in extrusion, promoted different molecular arrangements, which affected the material performance. The main results showed that DHT for 4 h in cassava starch produced bio-based plastics with increased mechanical properties and opacity while decreasing water permeability, moisture content and light transmittance. In conclusion, DHT showed to be an interesting alternative to produce biodegradable plastics with potential use in different industries. [Display omitted] • DHT promoted molecular changes resulting in a denser matrix. • For casting or extrusion, different polymeric matrix organization was obtained. • The faster drying in extrusion resulted in the formation of cracks and micro-void. • The slow drying in casting process resulted in an entangled matrix. • For casting or extrusion, DHT produced plastics with enhanced performance. [ABSTRACT FROM AUTHOR]

Abstract: The classic conservative approach for thermal process design can lead to over-processing, especially for laminar flow, when a significant distribution of temperature and of residence time occurs. In order to optimize quality retention, a more comprehensive model is required. A model comprising differential equations for mass and heat transfer is proposed for the simulation of the continuous thermal processing of a non-Newtonian food in a tubular system. The model takes into account the contribution from heating and cooling sections, the heat exchange with the ambient air and effective diffusion associated with non-ideal laminar flow. The study case of soursop juice processing was used to test the model. Various simulations were performed to evaluate the effect of the model assumptions. An expressive difference in the predicted lethality was observed between the classic approach and the proposed model. The main advantage of the model is its flexibility to represent different aspects with a small computational time, making it suitable for process evaluation and design. [Copyright &y& Elsevier]

Abstract: Biodegradable films based on cassava starch and with addition of natural antimicrobial ingredients were prepared using the casting technique. The tensile properties tensile strength (TS) [MPa] and percent elongation (E) at break [%] and the water vapor transmission (WVT) of the biodegradable films were evaluated and compared with the control (without antimicrobial ingredients). The evaluation of the Colony Forming Units per gram [CFU/g] of pan bread slices packed with the best biodegradable films, in terms of packaging performance, was also determined. The addition onto the matrix of only clove and cinnamon powders could reduce the films WVT when compared to the control, however TS and E were lower than the control and the effect of cinnamon was milder regarding this property. Since water activity of the pan bread slices packed with the biodegradable films increased considerably during the storage period, the antimicrobial effect could not be clearly determined. [Copyright &y& Elsevier]

Coconut water is an isotonic beverage naturally obtained from the green coconut. After extracted and exposed to air, it is rapidly degraded by enzymes peroxidase (POD) and polyphenoloxidase (PPO). To study the effect of thermal processing on coconut water enzymatic activity, batch process was conducted at three different temperatures, and at eight holding times. The residual activity values suggest the presence of two isoenzymes with different thermal resistances, at least, and a two-component first-order model was considered to model the enzymatic inactivation parameters. The decimal reduction time at 86.9 °C ( D86.9 °C) determined were 6.0 s and 11.3 min for PPO heat labile and heat resistant fractions, respectively, with average z-value = 5.6 °C (temperature difference required for tenfold change in D). For POD, D86.9 °C = 8.6 s ( z = 3.4 °C) for the heat labile fraction was obtained and D86.9 °C = 26.3 min ( z = 6.7 °C) for the heat resistant one. [ABSTRACT FROM AUTHOR]

Abstract: In the present study a virtual prototype of a four-channel plate heat exchanger with flat plates was developed using computational fluid dynamics (CFD). Parallel and series flow arrangements were tested and experimental results were compared to numerical predictions for heat load obtained from the 3D CFD model and also from a 1D plug-flow model. The CFD model represents channels, plates and conduits of the exchanger and takes into account the unequal flow distribution among channels and the flow maldistribution inside the channel. CFD results are in good agreement with experimental data, especially for the series arrangement. [Copyright &y& Elsevier]

Abstract: Bread partially baked for 7min at 250°C, after cooling, was frozen until core temperature reached −18°C and stored at this same temperature up to 7 days. Samples were removed daily from the freezer, thawed and baked at 250°C for 6min. Analyses were performed 1h after final baking, and were also conducted on fresh French bread daily produced (control). Weight and specific volume of frozen part-baked bread presented significant difference () compared with fresh one. Sensory analysis was carried out by a trained panel using the Difference from Control test to evaluate the difference and the degree of difference between frozen part-baked French bread (FPBFB) and fresh bread regarding appearance, tactile by direct touch and mouthfeel. All scores obtained indicated that the panelists, during the studied period, considered FPBFB to be slightly different compared with fresh one. Consumer Acceptance test was applied to compare appearance (gloss, roughness and cut on bread surface), oral texture (crust crispness and crumb firmness) and overall flavor between frozen part-baked bread and a commercial brand. All sensory scores obtained from Consumer test indicated that the 4-day frozen part-baked presented a superior acceptance to the commercial brand. [Copyright &y& Elsevier]

Thermal models of plate heat exchangers rely on correlations for the evaluation of the convective heat transfer coefficients inside the channels. It is usual to configure the exchanger with one countercurrent single-pass arrangement for acquiring heat transfer experimental data. This type of configuration approaches the ideal case of pure countercurrent flow conditions, and therefore a simplified mathematical model can be used for parameter estimation. However, it is known that the results of parameter estimation depend on the selected exchanger configuration because the effects of flow maldistribution inside its channels are incorporated into the heat transfer coefficients. This work presents a parameter estimation procedure for plate heat exchangers that handles experimental data from multiple configurations. The procedure is tested with an Armfield FT-43 heat exchanger with flat plates and the parameter estimation results are compared to those obtained from the usual method of single-pass arrangements. It can be observed that the heat transfer correlations obtained for plate heat exchangers are intimately associated with the configuration(s) experimentally tested and the corresponding flow distribution pattern(s). [Copyright &y& Elsevier]

Non-starch polysaccharides recovery from overripe bananas is challenging due to the high quantities of soluble sugars accumulated during the ripening process. Non-starch polysaccharides isolated from overripe bananas may be used as a functional ingredient. Kinetic extraction of soluble sugars from ripe banana (Musa cavendishii) using ethanol as solvent is presented. Different extraction methods (mechanical stirring and ultrasound-assisted), solid/solvent ratio (1:3 and 1:5) g⋅mL−1 and temperature (25 and 65) °C were investigated. Process efficiency was evaluated through the extraction index (EI), defined as the percentage of sugar extracted after 30 min. Soluble solid extraction curves were adequately represented by Patricelli and Peleg models, but only the Patricelli model represented the water extraction adequately. The condition that maximizes the soluble solids extraction and minimizes energy consumption was 1:5 g⋅mL−1 of solid/solvent ratio, 25 °C under mechanical stirring (EI = 87 ± 1 g ss extract /100 g ss banana). • Ripe bananas were used as a source of non-starch polysaccharides (NSP). • Conventional (SLE) and ultrasound-assisted extraction (UAE) are compared. • Equilibrium condition was achieved at 30 min, with high extraction index m. • SLE, low temperature and solvent amount extracted 87 g soluble solids /100 g banana. [ABSTRACT FROM AUTHOR]

The main objective of this work was to verify the efficiency of batch microwave-assisted heating for donor human milk and assess the activity of alkaline phosphatase (ALP) and microbiological quality. Processing was conducted at different temperatures between (50 and 80) °C and times from (5–300) s in order to evaluate the suitability of ALP as a target for the microwave process of donor human milk. The thermal inactivation of ALP followed first-order kinetics with a z -value of 4.4 °C that indicates a strong dependency of ALP inactivation with temperature. The optimal conditions (60 °C for 30 s) were determined, based on ALP inactivation, and the microbiological quality of the processed donor human milk was evaluated. No pathogens (mesophilic bacteria, coliforms at 35 °C, Salmonella spp. and Staphylococcus spp.) were detected after microwave-assisted heating and this suggests that this technology can be applied to ensure adequate safety and quality in Human Milk Banks (HMBs). • The microwave-assisted heating was tested in donor human milk (DHM). • Microwave-assisted heating was effective to inactivate the alkaline phosphatase in DHM. • At 60 °C for 30 s the ALP level was low (<1 μg of phenol/mL DHM). • Microwave process inactivated Salmonella and Staphylococcus aureus. [ABSTRACT FROM AUTHOR]