This study demonstrates the implementation of a Parsum real-time granule size monitoring system within the segmented fluid-bed dryer of the ConsiGmaTM25 continuous manufacturing line. Reference real-time patterns were established for granules produced at liquid-to-solid (L/S) ratios of 0.15, 0.3 and 0.4, developing a comprehensive understanding of granule size throughout the entire drying process. The in-line measurements were found to be influenced not only by the size of individual granules passing through probe's optics, but also by granules' movement as a population during the process. It was also highlighted that the filling phase causes erratic granule movement, which further affects the real-time characterisation. Increasing the L/S ratio resulted in the formation of larger granules and a significant reduction in granule detection rate - from a maximum of 2500 granules/s at L/S 0.15 to 270 granules/s at L/S 0.4 - while the moisture content post-drying ranged from 2.4 % to 10.8 %. Granules formed under the highest L/S ratio also imposed processing and measurement limitations due to extensive liquid bridge formation, ultimately leading to channelling. Furthermore, off-line validation confirmed that overlapping granules distort Parsum size estimations, particularly causing overestimations of the Dv90 percentile by up to 13.97 %. Lastly, to support real-time decision making and ensure compliance with regulatory guidelines for continuous manufacturing regarding determination of any irregularities during processing, intentional process disturbances were created. By varying the L/S ratio from 0.15 to 0.4 during operation, size deviations from reference trends were detected and characterised in-line, enabling detection of process deviations using sensory measurement techniques.

If not controlled, temperature and humidity may induce caking of amorphous food powders that can be a major issue during food granulation. Caking must be avoided because it results in the permanent loss of material and process failure. The impact of key process parameters to achieve controlled particle agglomeration by avoiding caking in a High Shear Granulator was assessed across a range of Maltodextrins. Findings reveal that increasing impeller speed, batch size and run time promoted the rate of heat generation in the system. The resulting increase in bed temperature was found to impact the different Maltodextrin powders to varying extents depending on the powder Tg, with high DE Maltodextrins showing greater sensitivity to temperature increases. This study also highlighted that high DE Maltodextrins require less water for effective granulation. This behavior correlated with the rate at which the water binder's viscosity increases as it incorporates Maltodextrin during granulation. High DE Maltodextrins demonstrated slower viscosity rises with increased solid composition than low DE counterparts, producing binder systems that remains mobile and adhesive at higher solid contents, thereby facilitating more efficient granulation. A parameter k mu was modelled to reflect this relationship. The parameters (T- Tg) and (L/S)/k mu were then used to produce a caking regime map for the High Shear Granulation system. This regime map delineates an optimal region for controlled agglomeration and a region where a high likelihood of caking occurs. The threshold of this caking region was set at a T-Tg of 40 degrees C and (L/S)/k mu value of 0.0325.

Many consumer food products such as confectionary or culinary seasonings are particle-based systems containing varying amounts of lipids such as oils, fats, and greases. Lipid migration is the result of inherent metastability of multiphasic particulate food systems. Lipid instability is further aggravated by climatic conditions, interaction with packaging, porosity, material transitions, and even gravity. Resulting lipid mobility can lead to various quality defects such as fat bloom on chocolate or oil stains on fibrous paper-based wrappers. This review revisits the factors influencing lipid migration and the generally accepted transport mechanisms diffusion and capillary flow. The most common measurement methods and modelling approaches described in the literature are discussed and assessed. Modern mitigation strategies to control lipid mobility are reviewed, with discussion on applicability to different particle-based food types and structures. Current trends towards healthier diets, clean-label recipes and sustainable packaging challenge traditional methods to stabilise lipids in food. As such a fundamental understanding, and measurement, modelling and mitigation strategies of lipid migration are highly relevant for a wide range of lipid-containing particulate foods.

Roller compaction is a widely used continuous dry granulation process in the food and pharmaceutical industries. The flow and distribution of the powder across the rollers in the compaction area plays a crucial role in determining the quality of the final product. Non-uniform powder flow and distribution across the rollers can lead to variations in quality across the ribbon, resulting in uneven qualities in the granules. Hence, it is essential to enhance the powder flow and distribution across the rollers in the compaction area. Besides that, insufficient compaction stress on both sides of the roller edges can also contribute to presence of uncompacted fines during compaction process. This research aims to systematically study a whole range of customized guiders design (T-1 until T-14) that improves powder flow and distribution across the rollers and reduces the percentage of fines in the compaction zone. The 3D printed customized guiders with different grade (1 mm until 14 mm) were applied in roller compactor with horizontal feeding system to control the amount of powder passing through the roller width by guiding more powder to the sides between the rollers and less powder to the centre. The effectiveness of the design was validated by examining crystalline and spray dry lactose powders with varying flowabilities using online thermal imaging. The results demonstrate a significant trend, indicating improved uniformity of powder flow and distribution across the rollers and reduced production of fines. These findings have the potential to contribute to long-term sustainability and resource conservation in industrial applications by reducing the need for material recycling and lowering energy consumption in continuous processes.

The homogeneity of particle suspension has attracted more attention in the fields of rehydrating infant milk formula and milk beverages. This work focus on size characterization of the floating, sticking (on the wall), suspended and settling particles involving both online and offline sizing techniques. Focused Beam Reflectance Measurement (FBRM) is a powerful online technique that is capable for measuring and analysing chord length distribution (CLD) of the suspended particles in liquid. It has been widely used in terms of monitoring size evolution of crystallization and sedimentation processes. In this work, a new approach that involves FBRM probe to measure the particle size distribution has been developed. The probe is placed at three different height levels in a standard container after one hour of free sedimentation. The results suggest that the finest fraction is dominant at all three heights but the percentage of it decreases with an increase of larger particles when looking at the bottom. Besides, all the floating, sticking and settling particles are collected and analysed, and the particle size distributions (PSDs) are obtained and compared using the offline sizing techniques, such as optical microscope and Camsizer. In the results, the suspended particle is the smallest one followed by the sticking and the floating particles, while the settling particle is the largest. However, for the sticking particles sticking on the wall, a great number of agglomerates is found during the test due to adhesion force, indicating that the size distribution might be overestimated. Based on the results, the target particle size range that can be stably suspended in the model suspension was selected by eliminating the unfavourable fractions.

In this research paper, the tablet strength as an indication of tabletability and tablet quality was examined and modelled as a function of different process parameters. The effects of the different process parameters of the various units of ConsiGmaTM -25 (i.e., wet granulation, drying, milling, blending and tabletting) were statistically examined. Then, a type-1 fuzzy based modelling framework based on the singular value decomposition-QR (SVD-QR) approach was developed and trained to mathematically map these parameters to the tablet strength. This structure was developed in a way that allows users to predict the tablet strength for tablets produced using different process parameters. Based on the results obtained, the statistical analyses show significant effects of the process parameters on the tablet quality. Furthermore, the proposed framework developed can be used to anticipate the tablet's strength successfully, where the performance measures in terms of the coefficient of determination and mean square error are 0.86 and 0.066, respectively. In addition, it can also provide users with linguistic understanding that can help in understanding as well as controlling the line.

Spray drying is currently the main method of industrial milk production because of its high drying speed and high process control accuracy. By controlling the parameters of spray drying process to control the characteristics of the milk powder is well researched. However, the drying mechanism in spray dryer is still not very clear. Methods of measuring single droplet drying kinetics are widely used instead of directly modelling spray drying kinetics.In this study, single droplet drying methods including sessile drying, filament hanging drying, and levitator drying in room temperature are used to compare and simulate the drying kinetics in spray dryer. Experiments show that the droplets in levitator are more spherical, but the final dry particles tend to be more donut-like due to the compression of the upper and bottom sides by the ultrasonic waves. In the filament hanging drying, the droplets are only suspended on the filament by friction. Due to gravity, the shape of the droplets and dried particles is non-sphere droplet shape. In sessile drying, the droplet is half-sphere shape, and the contact area is not changing because of capillary force. By comparison, the final particle morphologies of these are significantly different from those in the spray dryer, therefore, explore the characteristics of spray-dried droplets by monitoring the drying characteristics of single droplets may not suitable on some situation especially on multi-component materials.

Paper packaging for compacted or tabletted foods is seen as a key sustainable packaging of the future. Yet its fibrous structure is susceptible to absorb oils, fats, greases and other small molecules from the contacting food. Underlying phenomena associated with oil release from compacted food on fibre -based packaging, such as viscous liquid flow, capillarity, and gravity from compacted particle systems into fibre networks are not fully understood yet. As such, oil stain mitigation on packaging remains a challenge. Using model food tablets of 95% 500 and 50 mu m particle size with 5% sunflower oil as the liquid phase, this work employed for the first-time quantitative Raman spectroscopic chemical imaging (RCI) coupled with automated image quantification for comparison of oil flow dynamics between food compacts and contacting paper packaging. The extent of de -oiling from the compact and imbibed into paper showed similar exponential decay with time for both porous systems. For the first time, oil migration dynamics on the food compact surface was 2D visualised via Raman spectroscopy and showed markedly different trends with varying environment climatic conditions and compact microstructure. The larger particle system leaked up to 50% of oil into paper, whereas the 50 mu m system retained 100% of its oil, creating an effective internal oil barrier. This novel technique opens the way for further understanding liquid transfer between porous food media and harnessing microstructure engineering to increase food and packaging performance.

In this research, the Consigma25 Continuous Manufacturing (CM) Line is statistically analysed and modelled. First, the main effects plot is employed to examine the effects of different process parameters on the granules size and the tablet strength. Second, a modelling framework based on serial interconnected artificial neural networks is proposed to model the CM line by mapping these parameters to the granules size and the tablet strength. Then, Gaussian mixture models (GMMs) are adopted to characterize the error resulting from these networks in a way that helps in extracting more information and, as a result, improves the performance of the modelling framework. Validated on an experimental data set, the proposed interconnected framework can anticipate the characteristics of the granules and tablets produced using a specific blend of excipients with an absolute error percentage value of less than 12.3%. In addition, the GMMs have improved the predictive performance by 9.7%.

Little is known about the sustainability of competing granulation technologies, despite them being key and widespread industrial processes. This study has evaluated the sustainability of four prominent granulation technology pathways with respect to material wastage (Yield %), Specific Time (Hours/kg) and Specific Energy (kWh/kg). The Fluidised Bed Granulator proved to be the most material efficient while the Roller Compactor was the most time efficient. The energy efficiency of the granulators improved in the following order: Twin Screw Granulator, Fluidised Bed Granulator, High Shear Granulator and Roller Compactor. The wet granulation techniques proved to be the more energy inefficient technologies due to energy expensive sub stages such as drying. This was especially the case with the Twin Screw Granulator and High Shear Granulator where the actual granulating equipment only accounted for around 13% and 15% of the total energy consumed by the entire production pathway. Comparatively, the drying stage accounted for around 45% and 84% of the Twin Screw Granulation and High Shear Granulation production pathways. The different granulation technologies were shown to produce granules with significantly varying properties due to changing granule shape and porosities. The use of visual tools such as parallel co-ordinate graphs and radar plots alongside analytical methods such as priority scoring are suggested as important tools to help manufacturers choose the optimum process pathway based on these varying sustainability and granule suitability factors.

The pharmaceutical field is currently moving towards continuous manufacturing pursuing reduced waste, consistency, and automation. During continuous manufacturing, it is important to understand how both operating conditions and material properties throughout the process affect the final properties of the product to optimise and control production. In this study of a continuous wet granulation line, the liquid to solid ratio (L/S) and drying times were varied to investigate the effect of the final granule moisture content and the liquid to solid ratio on the properties of the granules during tabletting and the final tensile strength of the tablets. Both variables (L/S and granule moisture) affected the tablet tensile strength with the moisture content having a larger impact. Further analysis using a compaction model, showed that the compactability of the granules was largely unaffected by both L/S and moisture content while the compressibility was influenced by these variables, leading to a difference in the final tablet strength and porosity. The granule porosity was linked to the L/S ratio and used instead for the model fitting. The effect of moisture content and granule porosity was added to the model using a 3d plane relationship between the compressibility constant, the moisture content and porosity of the granules. The tablet tensile strength model, considering the effect of moisture and granule porosity, performed well averaging a root mean squared error across the different conditions of 0.17 MPa.

Dry powder mixing is a common process in the food industry. The aim of dry powder mixing is to improve the mixture quality within the optimum critical mixing time. Therefore, critical mixing time and mixture quality need to be monitored and quantified. An optical camera has advantages of high resolution, short image acquisition time and relatively large sam-pling area. An optical camera was used to online monitor the mixing process of the dairy-based powder and coffee powder of different sizes in a 5-L bin mixer. A new image analysis method including seven mixing indices and three dispersion indicators, has been developed. This method can provide precise results and identify different effects on mixing performance. This study confirms that the best mixing quality can be achieved when mixing particles of similar size. When the rotation speed is increased from 5 to 15 and 30 rpm, the critical mixing time is shortened.

Roller compaction is a continuous dry granulation process in which two counter-rotating rollers compress the powder. The feeding of powder to the compaction zone has a significant effect on product quality in the process. This work aims to improve ribbon property uniformity using new feeding guiders and develop a relationship map. The feeding guiders were designed in a range of grades considering the different powder properties and process parameters to achieve a uniform powder feeding to the compaction zone. An online thermal imaging camera was used as a process analytical technology to monitor the powder compaction and the uniformity of temperature across ribbon width, which was indirectly related to the powder distribution. The uniformity of the ribbon temperature of all powders increased from 20% using the original design to about 70% using the optimum design of the guiders, which indicated better powder distribution during the compaction. A relationship was also investigated for different materials with varying properties, grades of feeding guider and roller forces, which is useful for the design of experiments and predicting relative temperature uniformity of other materials.

This paper presents a flowsheet modelling of an integrated twin screw granulation (TSG) and fluid bed dryer (FBD) process using a Model Driven Design (MDD) approach. The MDD approach is featured by appropriate process models and efficient model calibration workflow to ensure the product quality. The design space exploration is driven by the physics of the process instead of extensive experimental trials. By means of MDD, the mechanistic-based process kernels are first defined for the TSG and FBD processes. With the awareness of the underlying physics, the complementary experiments are carried out with relevance to the kinetic parameters in the defined models. As a result, the experiments are specifically purposeful for model calibration and validation. The L/S ratio (liquid to solid ratio) and inlet air temperature are selected as the Critical Process Parameters (CPPs) in TSG and FBD for model validation, respectively. Global System Analysis (GSA) is further performed to assess the uncertainty of CPPs imposed on the Critical Quality Attributes (CQAs), which provides significant insights to the exploration of the design space considering both TSG and FBD process parameters.

Model-driven design approaches have great potential to improve current engineering workflows for wet granulation and other particulate processes. The key to model-driven design is a predictive process model. In this paper, a novel predictive model is proposed for high-shear wet granulation using a one-dimensional population balance modelling framework. The wet granulation mechanisms are represented by rate expressions which are based on mechanistic understanding. Material characterisation tests and granulation experiments are designed to verify critical modelling assumptions and determine the modelling parameters. Based on the Sobol' indices results from a parameter sensitivity analysis, the impactful parameters to estimate are identified: critical pore saturation, and coefficients for consolidation, collision and breakage. Only impactful parameters that cannot be measured are estimated to reduce the experimental effort and improve the model's predictive power. Lab scale experiments are designed to estimate parameters individually before fine-tuning the results. The model is assessed using a novel model validation workflow, which is based on predictions of experiments at four different scales from lab scale to pilot plant: 2 L to 70 L. (c) 2021 Elsevier B.V. All rights reserved.

Food powders often exhibit hydrophobic surface areas. To understand the effect of corresponding wettability variations on particle floating, which critically influences powder reconstitution, we studied floating of glass beads after creating surface heterogeneity by spraying cocoa butter. Force-position curves were recorded to characterise contact line pinning. Floating of particles with surface heterogeneities comprised a dynamic phase, which to our knowledge has not been reported previously. Measured forces varied due to contact line pinning/depinning. The results indicate that the dynamic floating phase is caused by gradual depinning. Steady-state floating is reached once pinning is sufficiently pronounced. We also demonstrate that surface heterogeneities complicate theoretical predictions of particle floating. The use of sessile drop contact angles for modelling was identified as an important source of error, as weak pinning points can affect contact angles but are oftentimes overcome during floating. Moreover, local pinning effects are not necessarily represented by a sessile drop. (c) 2021 Elsevier B.V. All rights reserved.

Spray-dried milk powders are characterized by an underrepresentation of hydrophilic compounds on the particle surface compared to the bulk, which renders reconstitution unfavourable. To overcome this issue, in the present study we instigated the coating of whole milk powder with two types of micronized lactose: crystalline and amorphous. We demonstrate that deposition of micronized lactose on the surface of whole milk powder leads to an increase in the reconstitution rate at 21 degrees C, correlated with a decrease in the apparent contact angle of the material. We also show that the physical solid state of micronized lactose is an important factor influencing the reconstitution performance of coated whole milk powder; If micronized lactose is amorphous, increasing the coating concentration beyond a certain point has little or no further effect on the reconstitution kinetics, which could be explained by viscosity build-up effects that hamper capillary penetration and sinking. (c) 2021 Elsevier B.V. All rights reserved.

Reconstitution of dairy powders is strongly influenced by the presence and physical state of fat on the particle surface. The present study investigates the effect of a micronized lactose coating on the physical state of the fat and the reconstitution kinetics of whole milk powder at four different temperatures (4/21/40/60 degrees C) and two stirring rates (400/800 rpm). For this purpose, two types of micronized lactose were used as coating materials: crystalline and amorphous. At 4 degrees C and 21 degrees C, the coated powders sink and are reconstituted faster than pure whole milk powder, regardless of the stirring rate applied. At 40/60 degrees C and 400 rpm, although the amorphous micronized lactose coating leads to a significant decrease in the reconstitution time, the crystalline coating has the opposite effect (or no effect). This discrepancy is related to the large differences in terms of dissolution enthalpy between the two micronized lactose physical states. It is posited that the dissolution of the coating material causes a temperature shift at the powder-water interface which could hamper the complete melting of surface fat and influence its viscosity, thereby affecting wetting and sinking. These differences are overcome at a high stirring rate (800 rpm) or if agglomerated whole milk powder is used as the host material.

Food powder reconstitution is frequently compromised by powder floating. Although particle floating has been studied for many years, several common properties of food powders have not been considered. To elucidate the effect of dissolution and hydrophobic surface defects, floating of pure and partially coated spherical sucrose beads was analysed. It was found that floating of soluble particles is characterised by a gradual increase of immersion depth which proceeds until the particle is fully engulfed and detaches from the interface. The duration of floating depends on initial floating position, immersion and dissolution velocity. Floating of partially coated beads is additionally affected by contact line pinning at coating material. Theoretical predictions, based on force balance analysis did not reflect the observed floating behaviour indicating that dissolution requires consideration of further factors. Particularly the observed formation of a convection current, which creates an additional downwards drag, is suggested to play a decisive role.