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Food foams are thermodynamically unstable systems. Their stabilization remains a challenge in the industry. To understand the interactions between an electrostatic field (SEF) and food foam, a microscopic study was conducted. Using a specially designed tensiometer, a liquid droplet (water, WPI solution, chickpea liquor) was placed between two parallel electrodes and subjected to an SEF (0 to 800 kV/m). Images of the pendant droplet were recorded throughout the experiment. Based on Laplace's equation, the surface tension was calculated as function of the applied voltage. The geometry of the droplet was deformed under SEF. The surface tension decreased proportionally to the rise of the voltage (γ distilled water = 21.7. 10 − 3 N/m at 800 kV/m). The mechanism causing surface tension reduction was found to be the electric charge existing on the liquid surface. By reducing surface tension, drops are likely to break up more easily during expansion, which improves the organoleptic qualities of the foam. • Tensiometer measures liquid droplets surface tension under electric field. • 3 model solutions used: water, WPI solution, and chickpea aquafaba. • For protein solutions, significant reduction of surface tension was determined. [ABSTRACT FROM AUTHOR]

Wheat malt has been widely used in food industry as an important source of endogenous enzymes, such as amylases. However, malting is a time-consuming process. Thus, this work proposed pulsed electric field (PEF) application to enhance wheat hydration, germination and amylase expression. Two-step hydration of Hendrix wheat variety was studied. PEF treatments (3 kV·cm−1; total energy applied of 9.9 and 19.8 kJ·kg−1) were applied with wheat in the water at the beginning or after the first hydration cycle. Hydration curves were accurately described by the Weibull exponential model (R2adj > 0.98). The more intense PEF treatments enhanced hydration rate (25%), water holding capacity (15%) and germination parameters when applied before the first hydration cycle. PEF enhanced α- and β-amylase activity by up to 104% and 25%, respectively, compared to control. Therefore, PEF can be used as a clean emerging technology to improve the malting process and malt quality. Growing concerns have gained attention regarding the use of synthetic enzymes or higher amounts of natural resources to perform enzymatic process to food applications. Malting cereals represents a clean technology to provide natural enzymes from natural resources, even though it is still considered a time- and energy-consuming method. In this sense, the use of pulsed electric fields (PEF) demonstrated to be a green and efficient technique to enhance the overall wheat malting process. Besides improving the process kinetics, the enzymatic activity and, thus, the quality of the final malt can be also improved. Because of that, malting producers can process wheat more rapidly to obtain more efficient ingredients when incorporating PEF to their processes. On the other hand, brewery and baking sector can use wheat malt stimulated by PEF as raw material with comparable technological effects as conventional malts, but in lower amounts instead. • PEF application enhanced the hydration rate of wheat by 25%. • PEF improved wheat germination power (up to 14%) and radicle development (2-folds). • Amylolytic capacity of wheat malt could be intensified by 104% with PEF pretreatment. [ABSTRACT FROM AUTHOR]

In the food industry, equipment surfaces with microbial entities can easily contaminate the food being processed, thereby leading to significant economic problems and even public health issues. To ensure the hygiene of materials in contact with food, cleaning processes are commonly implemented. Conventional strategies used for biofilm removal are energy and water intensive processes. Besides, they also use a substantial amount of chemicals. However, despite the strong enforcement of the conventional cleaning processes, each year, alarming statistics are reported by sanitary organizations, emphasizing the need of improving the safety and hygiene of equipment surfaces. Therefore, the investigation of strategies to effectively remove biofilm biomass is becoming essential. This literature review aims to describe the effectiveness of different physical strategies for biofilm biomass removal. Along with conventional physical methods (conventional CIP, water jet, and static foam cleaning) widely used in the food industry, other promising methods such as pulsed flow, bubble flow, foam flow, ice pigging, snow CO 2 , electromagnetic methods, plasma, and air jet were reported. Further, the principles, cleaning mechanisms, important process parameters, as well as, limitations associated with these methods have been discussed. All of these methods have shown a promising ability to remove biofilm, while some of them like foam flow and pulsed flow were found to be eco-friendly as they reduced environmental impacts based on LCA analyses. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Thermal treatments were applied to post-sprouted barley grains. • Enzymatic profile was assessed before and after the thermal treatments. • High enzymatic activity impaired the resulting bread-making properties. • Thermally treated malts improved dough fermentation, bread-making and bread quality. • Treatments at 70 °C/40 min showed the best overall performance in bread production. Malt flour represents a potential clean label bread improver, but a high enzymatic activity can lead to some bread defects. Thus, this study was focused on applying different thermal treatments (10 and 40 min; 70–90 °C) to green barley malt in order to promote a partial enzyme inactivation. The addition of 1.5 g of thermally treated malt (TTM) per 100 g of flour in wheat bread formulation was evaluated regarding the resulting bread-making properties, dough fermentation and overall bread quality. Activity of starch-degrading enzymes was not detectable above 80 °C/10 min. TTM incorporation improved the gas production by up to 60% during fermentation, mainly in formulations to which malts thermally treated under mild conditions have been added. Compared to untreated malt, thermal treatment reduced dough thermal weakening, improved gel strength during gelatinization and maintained low setback values. Bread collapse observed by baking follow-up was related to gas inflation and low mechanical resistance. Formulations with the addition of malts thermally treated at 70 °C for 40 min resulted in breads with higher specific volume, improved coloration and a crumb with slightly smaller pores than control and untreated malts. Thus, thermal treatment can be used as a technique to produce standardized malted flour to be used as clean label bread improvers. [ABSTRACT FROM AUTHOR]

Starch retrogradation and water loss have effects of the same intensity on the increase in firmness in the phenomenon of bread staling. Writing the equations of this system, in order to understand the mechanisms of water transfer in the vapour and liquid phases, is apparently simple. Nevertheless, choices are necessary for the simplifying hypotheses. Two models, differing in their geometry and their equations, were developed. Besides investigating the water transfer mechanisms in the vapour and liquid phases, the aim of this study is to compare the results of the two models and to conclude as to their individual interest. Concerning the physical phenomena, the study shows that a part of the water lost by the crumb escapes into the atmosphere while another part is absorbed by the crust. As regards the modelling the study shows that the most complete model is not the best choice and specifies the simplifying assumptions that should be retained or eliminated. [ABSTRACT FROM AUTHOR]

This study aimed to model an innovative process of pulsed microwave assisted freezing (MAF), which was expected to improve frozen product quality. The phase change model was based on spherical ice crystal growth and an original enthalpy formulation. The objective was to understand better the thermal interactions between microwaves and a product being frozen in a TE10 waveguide in which nitrogen gas and microwaves reach the product on the top surface. The 2D model was validated against the literature data and used to perform numerical simulations. The freezing front location and the reflection at air-product interfaces have a large impact on microwave behaviour in the product, especially on hot-spot displacement. As in some experimental works, temperature oscillations were observed. It is shown that their amplitude is related to the pulse duration. These results will help in designing experimental procedures to study the interest of using low energy pulsed microwaves during freezing. [ABSTRACT FROM AUTHOR]

The purpose of this study is to understand and describe the mechanisms occurring during the baking of a French crêpe product with a focus on the impact of the baking temperature on the formation of the “leopard” appearance. A French crêpe is a very thin bakery product (ca. 0.7 mm thick), which is baked in less than 20 s at 240 °C ± 20 °C in industrial conditions. Different microscopic techniques were used to understand the impact of the process parameters on the crêpe structure and the formation of the “fleur”. Crêpe baking is a very rapid process during which boiling occurs at selected locations of the crêpe-surface contact zone. The onset of boiling leads to the detachment of the crêpe batter from the baking surface: it is related to the balance between the resistance of the batter undergoing the baking transition and the vapor pressure inside the blister formed between the baking surface and the crêpe. [ABSTRACT FROM AUTHOR]

Freezing is the most popular and widely used food preservation method of the modern times. The freezing process of food matrices is related to their high water content and its metamorphoses into ice on cooling. The final quality of the frozen product is highly depended on the ice crystal morphology because it can cause irreversible damage on the microstructure of the food matrix. Supercooling and ice nucleation temperature need to be controlled both in suppressing and inducing the solidification to improve technological processes such as freeze drying, freeze concentration, cryopreservation, ice formation and cold-energy storage both in food industry and domestic preservation. However, the mechanism of freezing is not yet well known and it is affected by several factors. Several emerging technologies have been recently proposed for ice nucleation control during freezing. This review article is focused on the alternative freezing methods such as ultrasound waves, magnetic, electric, and electromagnetic field assisted freezing. In addition, the properties, mechanism of action and possible applications of electrofreezing are extensively discussed. [ABSTRACT FROM AUTHOR]

Experiments were carried out to study the effects of resting time (also well known as first proofing) on properties of dough and bread. Three resting times were used in the experiment: 0, 10 and 20 min. The results indicated that resting time significantly ( p < 0.05) affects the properties of dough and bread. Porosity of the dough increased with increase in resting time. Decrease in the number of smaller bubbles and increase in the median pore area of the bubbles present in the dough was observed as the resting time proceeded. Significant decrease ( p < 0.05) in torque value was observed with increase in resting time. Elastic recovery in terms of recoil strain was highest for 0 min resting followed by 10 and 20 min resting. Degassing was found to closely related to the air content of the dough as it was found that degassing increased with resting time. Bread specific volume and the porosity fraction increased, whereas median pore area in the bread crumb decreased with resting time. [ABSTRACT FROM AUTHOR]

Bread dough baking was investigated using ohmic heating technology. An experimental system was set up for the measurement of the electrical conductivity of bread dough during heating. The influence of temperature, salt content and degree of fermentation (porosity) on the electrical conductivity of dough was investigated. It was observed that it increased linearly with temperature, until starch gelatinisation during which the dough conductivity remained constant or slightly decreased. The conductivity increased linearly again after starch gelatinisation, but at a lower rate. The electrical conductivity of dough had a linear positive dependence on salt content, but decreased with increasing dough porosity. Numerical simulations of temperature increase were carried out and compared with experimental data. For a good correlation between numerical and experimental data, a corrective coefficient was numerically estimated and validated, taking into account mainly the conversion of electrical energy to heat, and geometric uncertainties. Numerical results showed that the linear evolution of temperature with heating time was mainly caused by heat losses. [ABSTRACT FROM AUTHOR]

The collapse of the sides of sliced bread is a technological problem for the baking industry. This study aims to understand the possible link between bread structures, internal pressure gradient, waiting time in the pan before depanning, and side collapse. The collapse variation was measured using laser to get bread profiles, and using image analysis of bread slices. The pressure variation at the centre and at the periphery was measured, and the product structure was observed using X-ray microtomography. The collapse increases with the cooling time in pan. The pressure in the cells is always higher than pressure in ambiance and cannot explain the collapse. The bread structure measurements indicate that the collapse is probably due to the cells shrinking of bread sides cells. A complementary explanation is to be searched in the specific volume variation of the material constituting the dough and the bread during the baking and the cooling. [ABSTRACT FROM AUTHOR]

Cake batters – made of flour, egg, sugar and fat – are complex systems. Ingredients interactions and their impact on protein secondary structure and starch conformational structures were studied in model batter systems using Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) spectroscopy. The results showed the possibility of using the pregelatinized starch without affecting protein conformation. The estimation of protein secondary structure highlighted the prevalence of α-helical structures in the model batter system, while β-sheets are predominant in flour systems as known in dough systems. The protein conformation in batter system is related to fat–protein interactions and could explain fat functionality in the final product. Starch crystallinity increased when each ingredient – except for pregelatinized starches – was added to the flour. Changes in starch conformation could be related to the redistribution of water between the batter ingredients. The overall results highlighted the importance of ingredients on the structural conformation of the batter polymers – starch and proteins – which could be the key factor to understand the functional properties of the batter. [ABSTRACT FROM AUTHOR]

Highlights: [•] A mathematical model of modified atmosphere packages (MAP) was developed. [•] The model was validated against experimental data for MAP of part-baked Sangak bread. [•] The model can be used to predict the quality stability of MAP products during storage. [•] Storage temperature had a large effect on the gas composition and volume of package. [•] The results showed the importance of obtaining accurate data of gas solubility in food. [Copyright &y& Elsevier]

Thermal conductivity of foods at high pressure (HP) is important for understanding the thermal response of food products during HP processing. Available information is still very limited, in this study, a line heat source (LHS) probe was installed in a HP vessel to evaluate pressure-dependent thermal conductivity of food and related materials. The probe was calibrated using agar gel (2%, w/w), resulting in an excellent linear agreement between measured values and reference data of pure water. Experiments were conducted to determine thermal conductivity of several materials at pressures up to 350 MPa and initial temperatures of 5 and 25°C. At given temperature and pressure, thermal conductivity depended on the nature of test samples and ranked in the decreasing order: water> fresh potato > lylose> chicken breast> salmon fillet> cheddar cheese. Thermal conductivity was sensitive to both pressure and temperature, increasing with both. Polynomial regression model was found to give a good fit for thermal conductivity as a function of pressure both at 5 or 25 `C. Results from this study were generally comparable to available published values thereby indicating the usefulness of the experimental approach for thermal conductivity data gathering. [ABSTRACT FROM AUTHOR]

• Raman spectroscopy was used to study gluten structure changes during mixing. • Raman spectroscopy measurements were performed directly in the dough matrix. • A thiol blocking reagent was used as a reducing agent to reduce disulphide bonds. • Intermolecular disulphide bonds are decisive for the stability of the gluten network. • Hydrophobic bonds are important in the structural evolution of dough during mixing. The aim of the present study was to evaluate Raman spectroscopy in determining changes that occur in the structure of gluten proteins induced during bread dough mixing. Raman spectra were measured directly within the dough. Three particular phases of mixing were studied: under-mixing, optimum mixing and over-mixing. A thiol blocking reagent, Tris(2-carboxyethyl)phosphine (TCEP) was then used to reduce disulphide bonds within proteins to confirm the important role of disulphide bridges in gluten network formation. For the control dough, the most important changes occurred during the optimum mixing phase when an increase in intermolecular disulphide bonds, anti-parallel β-sheet and α-helix structures was observed, combined with the hydrophobic burial of tryptophan and tyrosine residues. The addition of TCEP appeared to effectively reduce the formation of intermolecular disulphide bonds, anti-parallel β-sheet and α-helix structures and lead to a more disordered secondary protein structure. [ABSTRACT FROM AUTHOR]

In this study, the impacts of different heating rates (HRs) from 6 to 40 °C/min were investigated in terms of the 1H proton water mobility, starch microstructure, texture, soluble amylose (AM), amylopectin (AP) retrogradation and AM crystallization during staling. A degassed breadcrumb baked in a miniaturized baking system was used to ensure better time-temperature control during baking. Proton nuclear magnetic resonance (1H NMR) data showed that the evolution of the proton T 2 relaxation time decreased with increasing HR during staling. The amount of soluble AM, AP retrogradation degree, AM crystallization degree and crumb firmness tend to increase at higher HR. Environmental scanning electron microscopy (ESEM) observations showed that most starch granules in crumbs treated at higher HR exhibited strong deformation and disruption. These results confirmed that the increase in crumb firmness during staling with increasing HR was related to a higher level of starch disruption. This yielded a higher degree of separation between the AM and AP, which resulted in more pronounced water trapping in the starch crystals. The resulting dehydration of the matrix (gluten network, with AM gel surrounding of starch granules) yielded a loss in crumb softness, and crumb baked at higher HR tended to have a firmer texture and faster staling. [Display omitted] • First-order kinetic model confirms that higher heating rate yields faster staling. • Starch granules in crumbs treated at higher heating rate exhibits strong deformation. • Higher heating rate increases amylose leaching and crystallization during staling. • Faster baking increases gluten dehydration and water trapping by starch crystals. • Amylose crystallization followed by amylopectin retrogradation yields crumb firming. [ABSTRACT FROM AUTHOR]

• The quality of wheat flour has been studied over 30 months in selected condition. • Storage in a sealed container at −20 °C enabled the flour quality to be preserved. • The loss of quality was mainly due to lipid oxidation. • The Hagberg falling number was increasing for flours stored at 20 °C. This paper presents a study on the effect of storage conditions on wheat flour quality for 30 months. Such study may be of interest for research projects conducted over long periods. Wheat flours were stored in two types of packaging (permeable paper bags and watertight containers) and at two temperatures (ambient temperature and a cold storage room). Selected qualities parameters were evaluated regularly such as chemical stability, consistency, extensibility, resistance, water absorption, Solvent Retention Capacity and Gluten Index Performance. In addition, Near-Infrared Spectroscopy was used to monitor the flour's evolution and models were employed to predict certain parameters. The results showed that storage at ambient temperature led to significant modifications of flour parameters and baking performances, whereas storage at low temperature preserved the initial quality of the flour. A practical recommendation is to favour storage at low temperature in a sealed container to prevent interaction with oxygen and moisture uptake. [ABSTRACT FROM AUTHOR]

This work evaluated the impact of PEF on the structure, properties, and functionality of wheat and cassava starches focusing on 3D printing application. Aqueous starch suspensions were PEF-treated using three different combinations of field strength and total specific energy input (T1:15 kV/cm;25 kJ/kg; T2:25 kV/cm;25 kJ/kg; and T3:25 kV/cm;50 kJ/kg). The three conditions had the same effect on cassava starch (no damage on granules surface, reduction of peak apparent viscosity, firmer gels), while T3 promoted a greater effect on wheat starch (fractures on granules surface, reduction in peak apparent viscosity, and firmer gels). T3 condition was selected for further evaluation, revealing depolymerization, reduction of relative crystallinity, and gelatinization enthalpy, but no changes in functional groups. PEF-treated wheat starch resulted in 3D printing with a smoother surface and different texture, while PEF-treated cassava starch showed the same performance of native starch. Therefore, PEF affects differently each source, potentially enhancing 3D printing applications. • Pulsed electric field (PEF) was used to modify cassava and wheat starches. • The starch modification was focusing on 3D printability of hydrogels. • PEF treatment differently affected the properties of each starch. • PEF treatment improved the 3D printing capacity of wheat starch. • Modified cassava starch showed the same performance of native cassava starch. [ABSTRACT FROM AUTHOR]

An original device dedicated to additive manufacturing was developed to pre-bake cake batter. Its originality lies in the fact that pre-baking is ensured by ohmic heating implemented in a rectangular channel equipped with two parallel electrodes. Experiments and numerical studies were carried out and benchmarked. The rheological properties of the cake batter (non-Newtonian power-law fluid) and the influence of voltage and temperature on electrical conductivity were accommodated in the numerical model. Due to the low velocities of the very viscous products near the solid-liquid interface, it was found that the heterogeneity of the temperature at the nozzle outlet under continuous ohmic heating could lead to nozzle clogging when high temperatures are reached. Hot spots were identified in different areas of the channel, such as corners where the electric field is high and velocity is close to zero. A parametric study was performed on the impact of the thermophysical properties of the batter, showing that specific heat has a much greater impact than thermal conductivity on the accuracy of the temperatures computed. Analysis of the process parameters showed that a stronger electric field leads to a higher temperature gradient in the nozzle section. The temperature gradient decreases with electrode distance (d elect) and nozzle width (l). This model could be used to optimize the ohmic heating nozzle configuration, with the objective of obtaining a continuous flow of pre-baked cake batter, while preventing clogging. Such a system could be used as 3D printing head. Conventional 3D printing of bakery products is based on the deposition of a batter, followed by a baking. This study proposes an innovative approach based on a printing nozzle equipped with ohmic heating, with the objective of achieving a uniform temperature distribution and of obtaining high mass flow rate. Despite a significant temperature gradient in the baked batter at the exit of the nozzle, the obtained results showed that adjusting the nozzle geometry allows a reduction of the gradient. Further investigations are thus needed to reduce the temperature gradient and to accommodate expansion of the batter in the case of formulation using baking powder. The transfer of such concept for industry application may be doable in a close future. • Pre-baking of a cake batter circulating in a rectangular channel was investigated. • Ohmic heating (OH) was used, with the objective of a uniform temperature profile. • A 3D numerical model was developed to investigate the channel's geometry. • Hot spots were observed in the corners of the channel due to high voltage gradients. • A temperature difference up to 12 °C was observed at the channel exit for E = 65 V/cm. [ABSTRACT FROM AUTHOR]

• Dry heating treatment (DHT) modified wheat starch and its gels. • DHT promoted a slight depolymerization and reduction of the starch crystallinity. • Hydrogels based on DHT starch were stronger and showed the lowest syneresis. • DHT improved the 3D printability and diversified the texture of the printed samples. The futuristic technology of three-dimensional (3D) printing is an additive manufacturing that allows obtaining creative and personalized food products. In this context, the study of food formulations (named as "inks") to be processed through 3D printing is necessary. This work investigated the use of dry heating treatment (DHT), a simple and safe method, to improve the wheat starch properties aiming to produce hydrogels to be used as "inks" for 3D printing. Wheat starch was processed by dry heating for 2 (DHT_2h) and 4 h (DHT_4h) at 130 °C. Modified wheat starches showed an increase in granule size, but processing did not alter the granule's shape nor surface, neither alter the molecular functional groups. On the other hand, DHT promoted slight molecular depolymerization, and reduction of starch crystallinity. Hydrogels "inks" based on the modified starches showed lower peak apparent viscosity during pasting, higher structural strength at rest, higher resistance to external stresses, higher gel firmness, and lower syneresis than hydrogels based on native starch. The hydrogels based on starch DHT_4h showed the best printability (greater ability to make a 3D-object by layer-by-layer deposition and to support its structure once printed) and this "ink" showed better reproducibility. Another point observed is that DHT extended the texture possibilities of printed samples based on wheat starch hydrogels. These results suggested that DHT is a relevant process to improve the properties of hydrogels based on wheat starch, making this ink suitable for 3D printing application. [ABSTRACT FROM AUTHOR]

This paper presents a novel system able to determine in touchless conditions some rheological properties of bread dough, by application of a force driven by a short air-jet impulse, and the concomitant surface displacement measurement by a laser interferometer. In this work, it is shown that in the FPD (Food Puff Device) is based on the displacement measurement due to an air jet by a laser interferometer test, a "softening" of the bread dough along the kneading process is observed, although it is well known that the bread dough gets strengthened by the kneading. This paradox is explained by the fact that, during the kneading, not only the dough become smooth and elastic, but a certain air amount is incorporated in the form of small air bubbles. FPD provides an empirical short time rheology test exciting the time scales linked to the air bubbles entrapped in the dough, so that the surface displacement is mainly due to the dough aeration. Demonstrating a good sensitivity to the air content, the FPD test seems a relevant method to follow the kneading process, in the aim of developing a tractable and efficient supervision tool. The bulk properties of the dough are also measured by a conventional creep recovery test in a rotational rheometer. An attempt of modelling the viscoelastic behavior in FPD treated like a creep-recovery test is proposed here, to provide some insights in the baking monitoring. • FPD (Food Puff Device) is based on the displacement measurement due to an air jet by a laser interferometer. • This exploratory study of the FPD shows feasibility for bread dough monitoring. • First results showed that the FPD is adapted for in-line or on-line control of bread dough aeration during kneading. • A Generalized Kelvin-Voigt system is used to model the dough creep-recovery test induced by the air-jet. [ABSTRACT FROM AUTHOR]

Among innovative freezing processes, electromagnetic wave assistance during freezing has received great attention in recent years. The literature provides interesting studies indicating that smaller ice crystals may be obtained during freezing with the assistance of microwaves. In the companion paper, we designed a laboratory scale prototype to perform experiments of this type in well controlled conditions at 2.45 GHz. In the current study, we performed freezing experiments using this prototype and developed a protocol to measure ice crystal sizes using X-ray micro-tomography. The methodology was first validated by measuring ice crystal distribution in unidirectional conventional freezing. Then several microwave assisted freezing modalities were studied. Experiments were conducted with pulsed and continuously applied microwaves. The impact of microwave irradiation time was studied at a constant incident microwave power, and then at constant energy supplied to the system. We observed a significant reduction of up to 25% in ice crystal size when microwave assistance was used during freezing with both pulsed and continuously applied microwaves. These observations tend to disconfirm the hypothesis in the literature according to which ice crystal size reduction is due to temperature oscillations. The only remaining hypothesis in the literature is that ice crystal size reduction may be due to the perturbation of the H-bond network in water, which could be a precursor to crystalline structure. It appeared that at constant incident microwave power, the increase in irradiation time tended to decrease ice crystal size. No significant difference in ice crystal size reduction was observed for a constant energy supplied to the system. The amount of energy supplied by microwaves seems to be a factor influencing ice crystal size. Industrial relevance Microwave assisted freezing is an emerging process which permits reducing ice crystal size, and thus improving frozen product quality. The measurement of ice crystals in samples frozen in controlled conditions of both freezing and microwave irradiation allows studying the main parameters that induce the reduction of their size. Better understanding of the relevant factors influencing nucleation and/or crystal growth can help to optimize the process. • Ice crystal size is measured by X-ray micro-tomography after freeze-drying. • The X-ray micro-tomography method is validated for conventional freezing. • Microwave assistance during freezing significantly reduces ice crystal size (−25%). • Ice crystal size reduction is not due to temperature oscillations. • Increasing the amount of energy supplied by microwaves decreases ice crystal size. [ABSTRACT FROM AUTHOR]

• MAF has been applied to apple and potato to reduce freeze damage. • MAF of apples and potatoes was performed under constant and pulsed microwave power. • The temperature profile was minimally affected by the microwave emission. • MAF process produced a better microstructure than the control condition. • Drip loss was reduced in the case of application of MW during freezing process. This study considered the effect of low energy microwave assisted freezing (MAF) on freezing time and quality attributes (microstructure, texture, drip loss and colour) of apple and potato. MAF of apples and potatoes was performed by applying constant microwave (MW) power (167 W/kg) and pulsed MW power (500 and 667 W/kg with 10 s pulse width and 20 s pulse interval resulting in an average power of 167 and 222 W/kg) during the freezing process. The temperature profile was monitored during the freezing process, and the microstructure was examined using X-ray micro-tomography and cryo-SEM. Other quality parameters such as texture, drip loss and colour were evaluated with thawed samples. It appeared that the freezing time was not affected by the MAF process. It is the first time that a MAF process is used for freezing plant-based products and showed that the application of microwaves during freezing process caused less freeze damage than the control condition. [ABSTRACT FROM AUTHOR]

• Dry heating treatment was used to modify cassava starch focusing on printability of gels. • Dry heating treatment period, gelatinization conditions and storage period were investigated. • The gelatinization conditions affected the gel strength differently for control and treated starches. • The highest storage period promoted increase in gel firmness only for the treated starches. • Dry heating treatment with 4 h resulted in hydrogels with the best printability. 3D printing is a technology capable of presenting creative, unique and intricate items in an attractive format, with specific compositions. However, novel ingredients must be developed to satisfy this new technological requirement. This work proposes dry heating treatment (DHT), a simple physical technique, as a method for modifying cassava starch, with particular focus on its use for 3D printing. DHT processing was conducted at 130 °C for 2 and 4 h (named DHT_2h and DHT_4h, respectively). Different gelatinization conditions (65, 75, 85, and 95 °C) were applied, and the hydrogels were evaluated considering different storage periods (1 and 7 days). Cassava starch properties were evaluated, focusing on the application of its hydrogels to 3D printing. The increase of DHT time produced a starch with higher carbonyl content and bigger granule size. It also reduced the water absorption index, increased the water solubility index, affected granule crystallinity and reduced molecular size. The longest storage period increased gel firmness. Increasing the temperature used in the gelatinization process reduced the gel strength of the native and DHT_2h. DHT_4h showed the lowest peak apparent viscosity and provided the strongest gels for all the evaluated conditions. Gels produced with DHT starches exhibited better printability than the native starch, mainly for the DHT_4h. This treatment was chosen to print 3D stars, and displayed better resolution than the native gels. Therefore, by using DHT, it was possible to obtain hydrogels with enhanced pasting properties, gel texture, and printability, thereby expanding the potential of applying cassava starch to 3D printing. [ABSTRACT FROM AUTHOR]

This study investigated the effects of microwave-assisted freezing on the quality attributes of button mushrooms ( Agaricus bisporus ). Four levels of microwave power (0, 10, 20, 30%) were applied to the mushroom samples during freezing. The quality attributes of the frozen and thawed mushrooms were then evaluated. The results suggested that higher microwave power produced the smaller and more uniform ice crystals. Moreover, the browning index of the mushroom samples increased with increasing microwave power. The textural properties (hardness) of the mushrooms were also affected by the microwave power, showing higher values as the power increased. Furthermore, the ratio of the microwave operating system's power to the freezer power was low and approximately 20% at the highest power level. Therefore, these findings confirm the potential of microwave-assisted freezing for reducing freeze damage to mushroom tissue and, thus, provide frozen mushroom with a better texture.

The emerging world of 3D food printing is reviewed. Its role in food manufacturing, including benefits and impacts, underemphasized gastrophysical aspects, and limitations are discussed. Foods can be digitally designed and physically prepared using the layer-by-layer deposition of food components, unleashing opportunities to deliver nutritionally personalized food and new food-human interactions. Existing bottlenecks, under-researched gastropsychophysical aspects, and the lack of harmonized standards hindering its use for mass production are mentioned., (© 2024. The Author(s).)

The present article responds to the food engineering community's growing interest in an emerging and lauded approach to food preservation, popularised by its developers as ' isochoric freezing '. A strong campaign in the scientific literature and mass media has recently promoted this technique as a universal replacement for traditional food freezing and the frozen supply chain by highlighting a number of alleged advantages of ' isochoric freezing '. Some of these claims therefore require a more neutral and critical assessment against the background of the today's state of the art in food freezing technologies. Hence, this article spotlights several concerns regarding the plausibility, energy expenditure, resource efficiency, process rate, throughput and safety of ' isochoric freezing ', as well as the correct use of food refrigeration terminology. The aspects considered are intended to make food scientists, technologists and engineers more aware of the real capabilities and the application perspectives of this still immature mode of refrigerated food processing.

Background: Sweeteners and sweetness enhancers (S&SE) are used to replace energy yielding sugars and maintain sweet taste in a wide range of products, but controversy exists about their effects on appetite and endocrine responses in reduced or no added sugar solid foods. The aim of the current study was to evaluate the acute (1 day) and repeated (two-week daily) ingestive effects of 2 S&SE vs. sucrose formulations of biscuit with fruit filling on appetite and endocrine responses in adults with overweight and obesity., Methods: In a randomised crossover trial, 53 healthy adults (33 female, 20 male) with overweight/obesity in England and France consumed biscuits with fruit filling containing 1) sucrose, or reformulated with either 2) Stevia Rebaudioside M (StRebM) or 3) Neotame daily during three, two-week intervention periods with a two-week washout. The primary outcome was composite appetite score defined as [desire to eat + hunger + (100 - fullness) + prospective consumption]/4., Findings: Each formulation elicited a similar reduction in appetite sensations (3-h postprandial net iAUC). Postprandial insulin (2-h iAUC) was lower after Neotame (95% CI (0.093, 0.166); p < 0.001; d = -0.71) and StRebM (95% CI (0.133, 0.205); p < 0.001; d = -1.01) compared to sucrose, and glucose was lower after StRebM (95% CI (0.023, 0.171); p < 0.05; d = -0.39) but not after Neotame (95% CI (-0.007, 0.145); p = 0.074; d = -0.25) compared to sucrose. There were no differences between S&SE or sucrose formulations on ghrelin, glucagon-like peptide 1 or pancreatic polypeptide iAUCs. No clinically meaningful differences between acute vs. two-weeks of daily consumption were found., Interpretation: In conclusion, biscuits reformulated to replace sugar using StRebM or Neotame showed no differences in appetite or endocrine responses, acutely or after a two-week exposure, but can reduce postprandial insulin and glucose response in adults with overweight or obesity., Funding: The present study was funded by the Horizon 2020 program: Sweeteners and sweetness enhancers: Impact on health, obesity, safety and sustainability (acronym: SWEET, grant no: 774293)., Competing Interests: Declaration of interests JCGH and JAH are in receipt of research funding from the American Beverage Association. ARA has received honoraria from Nestle, Unilever and the International Sweeteners Association. University of Liverpool has received income from International Food Information Council by CH. CH has received honoraria for work with Food Standards Agency Advisory Committee on Social Sciences. MW was previously contracted to research funded by AstraZeneca through funding paid to University of Liverpool. CS is a paid employee of Cargill, Inc. The University of Leeds has received income from consultancy for Mars Inc by JCGH. EAR has received honoraria for manuscript writing from Institute of Life Sciences (ILSI-Europe)., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

In most soft wheat products such as cakes, baking powder (BP) plays an important role in achieving the desired product volume through batter aeration by the release of CO 2 during baking. However, the optimization of a blend of constituents in BP is minimally documented, especially the selection of acids, which is often supported by the suppliers based on their experience. The objective of this study was to evaluate the impact of two sodium acid pyrophosphate leavening acids (SAPP10 and SAPP40) at different levels in BP on final pound cake properties. A central composite design of the response surface methodology (RSM) was used to design the blend ratio of SAPP with different amounts of BP to investigate some selected cake parameters such as specific volume and conformation. Results showed that increasing the BP level significantly increased the batter specific volume and porosity but dropped as BP approached maximum (4.52%). The batter pH was influenced by SAPP type; SAPP40 presented a relatively sufficient neutralization of the leaving system as compared to SAPP10. Furthermore, lower BP levels resulted in cakes with large air cells, which presented a non-homogeneous crumb grain. This study therefore highlights the need to identify the optimum amount of BP to attain the desired product qualities.

This study investigated the impacts of the complete substitution of sucrose by maltitol and/or sorbitol on the dough-crumb transition in biscuits. To this end, the phenomena of starch gelatinization/melting were studied at different moisture contents, both in the biscuit dough and model systems, by X-ray diffraction (XRD), differential scanning calorimetry (DSC), and by environmental scanning electron microscopy (ESEM). Observation of doughs in ESEM revealed sorbitol had a structure very different from sucrose and maltitol crystals. After forming the dough pieces, it could be seen that at least some sugar and maltitol crystals were still present while sorbitol flakes were solubilized. At a limiting real water content (~20% dry basis), adding sweeteners to the mixture increased the gelatinization temperature, more markedly for sucrose and maltitol, as well as increasing the enthalpy. These results were confirmed by the model systems analyses. The calorimetric study with mixing batch cells revealed that sorbitol dissolved completely while maltitol and sucrose competed with the flour constituents to capture water. The proportion of water available for the sorption of the starch grain and its gelatinization was therefore different according to the affinity of the sweetener for water, and might influence the degree and temperature of starch gelatinization/melting.

The impact of hydrothermal processing undergone by bread dough during baking on the degree of starch granule disruption, on leaching of soluble amylose, on water mobility, on firmness and on amylopectin retrogradation during staling has been investigated. Two heating rates during baking have been considered (4.67 and 6.31 °C/min) corresponding respectively to baking temperature of 220 and 240 °C. An increase in firmness and in the amount of retrogradated amylopectin accompanied by a decrease in freezable water has been observed during staling. Although a lower heating rate yielded in larger amount of retrogradated amylopectin retrogradation, it resulted in a lower firmness. Additionally, the amount of soluble amylose and the relaxation times of water measured by Nuclear Magnetic Resonance NMR (T20, T21 and T22) decreased during staling. It was demonstrated that the amount of soluble amylose was higher for bread crumb baked at lower heating rate, indicating that an increasing amount of amylose is leached outside the starch granules. This was corresponding to a greater amount of retrograded amylopectin during staling. Moreover, it was found that the degree of gelatinization differs locally in a same bread slice between the top, the centre and the bottom locations in the crumb. This was attributed to the differences in kinetics of heating, the availability of water during baking and the degree of starch granule disruption during baking. Based on first order kinetic model, it was found that staling kinetics were faster for samples baked at higher heating rate.

Cylindrical specimens (50 mm diameter and 160 mm length) of fresh pork muscle (boneless rib portions) packed in plastic bags were frozen by pressure shift freezing (PSF) at 100, 150, and 200 MPa, air blast freezing (ABF), and liquid immersion freezing (LIF). Temperature and phase transformations of the muscle tissue were monitored during the freezing process at three locations: center, midway between the center and the surface, and near the surface. Pork muscle quality changes [color, drip loss (both thawing and cooking), texture (shear force), and protein stability (DSC thermal profiles)] were evaluated after thawing the frozen samples at room temperature (20 degrees C). Employing pressures above 150 MPa caused very significant (P < 0.01) color changes in pork muscle during the PSF process. The PSF process reduced thawing drip loss of pork muscle but did not cause obvious changes in total drip loss following thawing and subsequent cooking. PSF at 150 and 200 MPa resulted in considerable denaturation of myofibrillar proteins of pork muscle. The PSF process also caused an increase in the pork muscle toughness as compared with that of unfrozen, ABF, and LIF samples.