Plant-based Food Materials Research Articles

Prediction of food materials for the management of respiratory symptoms targeting PDE4B and NMDAR via machine learning approach

This study was conducted to explore the potential of plant-based food materials as reservoirs of natural active compounds for the management and prevention of respiratory diseases focusing on relief of symptoms including inflammation and cough. Herein, this research suggests the dietary choices that incorporate active compounds capable of targeting various respiratory symptoms simultaneously. To identify active compounds that regulate respiratory symptoms by targeting N-methyl-D-aspartate receptor (NMDAR) and Phosphodiesterase-4B(PDE4B), we adopted a systemic process integrated with machine learning. Through this process, the active compounds and food materials were predicted in an efficient manner. Additionally, we propose potential applications for drug candidate discovery and suggest assessing toxicity and safety through inter-material interactions.

Effect of different hydrocolloids on the physicochemical, printing, and digestion properties of 3D printed purple sweet potato

This study investigated the influence of different hydrocolloids, namely hydroxypropyl methylcellulose, xanthan gum, guar gum, flaxseed gum, and κ-carrageenan gum on the physicochemical, printing, and digestion properties of 3D printed purple sweet potato (PSP). Aside from κ-carrageenan gum, addition of these hydrocolloids could improve the 3D printing performance of PSP. Addition of hydrocolloids significantly altered the water mobility and rheological characteristics of PSP. The tanδ (G”/G’) values of PSP-hydrocolloid mixtures were strongly related to their 3D printability. The hydrogen bonds in PSP-hydrocolloid samples were weakened compared to PSP-H2O. In comparison to other hydrocolloids, the addition of guar gum significantly decreased the level of starch digestion in PSP during in vitro digestion. The release of phenolics and anthocyanins was highly correlated with the extent of starch digestion. The variations in interactions between hydrocolloids and phenolics affected the release of individual phenolics from PSP during gastrointestinal digestion and colonic fermentation. PSP-guar gum exhibited a significantly higher content of phenolics released after colonic fermentation than the other PSP-hydrocolloid samples. Overall, this study provided theoretical guidance for addition of hydrocolloids into plant-based food materials to enhance their 3D printing performance and modulate their release of intrinsic bioactives as well as digestion of starch during gastrointestinal digestion and colonic fermentation.

Physicochemical and Functional Properties of Yeast-Fermented Cabbage.

Microbial fermentation is often used to improve the functionality of plant-based food materials. Herein, we investigated changes in the physicochemical and functional properties of cabbage during yeast fermentation to develop new products using fermented cabbage. Among the 8 types of food-grade yeast, both Saccharomyces cerevisiae and Saccharomyces boulardii fermented 10% cabbage powder solution (w/w) the most effectively, leaving no soluble sugars after 12 h of fermentation. In addition, the yeast fermentation of cabbage resulted in functionally positive outcomes in terms of sulforaphane content, antioxidant properties, and anti-inflammatory activity. Specifically, the yeast-fermented cabbages contained about 500% more sulforaphane. The soluble fraction (5 μg/ml) of yeast-fermented cabbage had no cytotoxicity in murine RAW 264.7 cells, and the radical-scavenging capacity was equivalent to 1 μg/ml of ascorbic acid. Moreover, cabbage fermented with S. boulardii significantly suppressed both lipopolysaccharides (LPS)-induced nitric oxide production and LPS-induced reactive oxygen species production in RAW 264.7 cells, suggesting a potential anti-inflammatory effect. These results support the idea that yeast fermentation is promising for developing functionally improved cabbage products.

Mathematical Modelling of Heat and Mass Transfer during Jackfruit Drying Considering Shrinkage

Shrinkage is an obvious phenomenon that occurs when drying plant-based food materials, and it has a crucial influence on heat–mass transfer mechanisms, energy consumption in drying, and dried product quality. The present study aims to develop a theoretical shrinkage model considering the drying kinetics and shrinkage velocity approach during the convective drying of jackfruit. Since there is no theoretical model in the literature that considers the transfer process along with shrinkage phenomena for jackfruit drying, this work focuses on presenting the drying and shrinkage kinetics behaviour through the development of a mathematical model. Two distinct models were developed, each considering the presence or absence of shrinkage phenomena. Model validation was carried out by comparing the predicted results with experimental data from drying tests conducted at 60 °C, and model accuracy was evaluated through statistical error analysis. In the shrinkage-induced model, the shrinkage exhibited a linear relationship with drying time, as the moisture content decreased from 5.25 to 0.47 kg/kg on a dry basis when the temperature increased to 54 °C. Notably, the shrinkage-induced model demonstrated superior performance, displaying low mean absolute error (MAE) values—0.27 kg/kg on a dry basis for moisture content, 2.07 °C for temperature variation, and 0.04 for shrinkage, when compared to the model without shrinkage. Furthermore, the mean relative error (MRE) values for the shrinkage-induced model were 45.71% and 33.33% lower than those of the model without shrinkage for average moisture content and temperature, respectively. The findings of this study provide valuable insights for the food drying industry, offering new knowledge about drying kinetics and shrinkage characteristics that can contribute to the development of energy-efficient drying systems.

A novel physics-informed neural networks approach (PINN-MT) to solve mass transfer in plant cells during drying

Predicting microscale mechanisms of plant-based food materials has been an enduring challenge due to the inherent complexity of involved physics and prohibitively-high computational costs. As an alternative to conventional methods of solving corresponding Partial Differential Equations (PDEs), Physics-Informed Neural Networks (PINNs) have recently received significant attention from the research community. This article investigates the feasibility of PINNs' Automatic Differentiation (AD) to solve mass transfer (PINN-MT) and effectively predict cellular-level mass loss and subsequent moisture variations during low-temperature drying. PINN-MT has been developed by incorporating the residuals of convective mass transfer equation, Fick's law of diffusion and relevant initial conditions into the loss function. The integration of Adaptive Activation (AA) and Transfer Learning (TL) leads to improved computational efficiency, prediction accuracy and consistency. To the best of the authors' knowledge, this study is the first of its kind to apply PINNs' AD to solve mass transfer for food-drying. The PDE-solving capacity of the proposed approach has been compared with that of the state-of-the-art Finite Element Analysis (FEA) techniques. Compared to benchmark FEA results, percentage errors for PINN-MT-based mass loss and moisture distribution predictions remain below 0.23% and 0.33%, respectively. In addition, TL enhances the solution-based prediction efficiency of PINN-MT by more than 80%. Further, a novel approach has been proposed to achieve time-efficient predictions by feeding mass transfer coefficient-hm as an independent input to the proposed predictive framework, which has the potential to tackle complex and highly non-linear physics-based models, where conventional computational approaches usually struggle.

Generalized moisture diffusivity for food drying through multiscale modeling

Drying plant-based food materials can be time consuming and energy intensive, making optimization of its processes essential. However, current mathematical models are plagued with condition-dependent diffusivities restricting their performance in developing optimal drying strategies. Multiscale modeling is one technique which can help transition towards a more physics-based approach, improving model's predictive capabilities. This research constructs a multiscale food drying model utilizing a generalized moisture diffusivity to investigate its predictive capabilities. The study investigates two food materials (apple and potato) convective drying at two different temperatures (47 °C and 64 °C). Additionally, to be able to utilize the generalized diffusivity, cell rupturing must be considered. Therefore, a theoretical rupturing threshold was developed exploiting the equilibrium vapor pressure to recognize which transport mechanisms were occurring. The generalized diffusivity was able to distinguish between the two materials and was able to describe the experimental data accurately at both drying temperatures. The generalized property resulted in diffusivities with the range of 1.94 × 10 −10 -5.14 × 10 −10 m 2 /s. • A multiscale model with a generalized diffusivity for food drying is investigated. • Multiscale model investigates two materials drying at low and medium temperatures. • Theoretical cell rupturing threshold is developed using equilibrium vapor pressure. • Multiscale model can predict if and when cell rupturing occurs.

A New Approach for Quantifying Purpurogallin in Brewed Beverages Using LC-MS in Combination with Solid Phase Extraction.

Purpurogallin (PPG) is a phenolic compound known for its high antioxidant properties in plant-based food materials. However, there is no easy and reliable method for direct determination of PPG in brewed beverages owing to its hydrophobicity, which makes it hard to separate from the background hydrophobic components. Therefore, a method employing solid-phase extraction (SPE) and liquid chromatography-mass spectrometry (LC-MS) was developed for detection and quantification of PPG in brewed beverages, and PPG content was quantified in commercial coffee, cocoa, and tea samples. The limits of detection and quantification were 71.8 and 155.6 ng/g dry weight (dw), respectively. The recovery with SPE was 26.6%. When combined with acetonitrile extraction (ANE), the recovery was 6.8%, higher than 2.6% with water extraction (WTE). Test tube extractions were better than moka pot brewing (MPB) for PPG quantification. Total PPG content of ground coffees prepared by ANE, WTE, and MPB ranged between 635 and 770, 455 and 630, and 85 and 135 ng/g dw, respectively. PPG was detected in two English breakfast tea samples (335–360 ng/g dw) using WTE, but not in cocoa samples. ANE showed higher (p < 0.05) PPG levels, but WTE (r = 0.55, p < 0.01) correlated better with MPB than ANE (r = 0.43, p < 0.01). The result indicated that WTE is the best method to determine PPG in brewed beverages. This work demonstrated that PPG was significant in brewed coffee, and our pioneer study in developing the method for beverage sample preparation and LC-MS analysis has made possible industrial applications and provided new perspectives for future research.

Fermentation Affects the Antioxidant Activity of Plant-Based Food Material through the Release and Production of Bioactive Components.

This review reports on the effects of fermentation on the chemical constituents and antioxidant activity of plant-based food materials. Fermentation involves a series of reactions that modify the chemical components of the substrate. It could be considered a tool to increase the bioactive compounds and functional properties of food plant materials. Oxidative damage is key to the progression of many human diseases, and the production of antioxidant compounds by fermentation will be helpful to reduce the risk of these diseases. Fermentation also can improve antioxidant activity given its association with increased phytochemicals, antioxidant polysaccharides, and antioxidant peptides produced by microbial hydrolysis or biotransformation. Additionally, fermentation can encourage the breakdown of plant cell walls, which helps to liberate or produce various antioxidant compounds. Overall, results indicated that fermentation in many cases contributed to enhancing antioxidants’ content and antioxidant capacity, supporting the fermentation use in the production of value-added functional food. This review provides an overview of the factors that impact the effects of fermentation on bioactive compound composition and antioxidant activity. The impacts of fermentation are summarized as a reference to its effects on food plant material.

Dehydration mechanisms in electrohydrodynamic drying of plant-based foods

Electrohydrodynamic drying (EHDD) is an energy-efficient and non-thermal technique for dehydrating heat-sensitive biological materials, like fruits, vegetables, or medicinal plants. Although this method has been studied for more than three decades, still little is known about the relative contribution of the different dehydration mechanisms in EHDD. An accurate understanding of the impact of the different EHD-driven mass transfer processes inside the food and its surrounding air is essential for a targeted future optimization and successful upscaling of EHDD technology. Examples of these dehydration mechanisms are convective moisture removal, electroporation of the cell membrane, or electro-osmotic flow in the fruit. In this modeling study, we first identify possible dehydration mechanisms for mass transfer during the EHDD process of plant-based food materials. Using available theoretical models, we then estimate the relative contribution of each dehydration mechanism to the overall mass transfer during the constant rate period and rank them based on their contribution. We show that convective dehydration by ionic wind is the dominant dehydration mechanism, with a contribution of about 93% to the overall water flux for a capillary-porous material. Cell-membrane electroporation is the second important driving force that increases the contribution of the transmembrane water flow to about 6.5% of the total mass flux in fruit tissue. The contribution of all the other water transport mechanisms is only 0.5%. These insights provide a stepping stone towards developing a full physics-based model of the dehydration process by EHD, including the falling rate period.

Chemical analysis and classification of black pepper (Piper nigrum L.) based on their country of origin using mass spectrometric methods and chemometrics

The current study applied gas chromatography-mass spectrometry (GC–MS), liquid chromatography-mass spectrometry (LC-MS), and thermal desorption direct analysis in real-time mass spectrometry (TD-DART-MS) methods to the analysis of black pepper (Piper nigrum L.) samples from different countries. The black pepper powder samples were analyzed directly by TD-DART-MS without any extraction, but for GC–MS and LC-MS methods, a methanol extraction procedure was employed before the analysis. Various compounds, such as piperamides and terpenes, were detected. Partial least squares-discriminant analysis (PLS-DA) was used to classify black pepper samples based on their origins. Total ion mass spectrum (TMS) data profiles from GC–MS, LC-MS, and TD-DART-MS methods were constructed and evaluated for the performance of classification. A cubic-root data transformation was tested in the data preprocessing and found to be effective for improving the classification rates. The average classification rates of PLS-DA models with GC–MS-cubic-root-TMS, LC-MS-cubic-root-TMS, and DART-MS-cubic-root-TMS data representations were 94.1 ± 0.6%, 87.7 ± 0.6%, and 97.0 ± 0.3% respectively, for 100-time bootstrapped-Latin-partition cross-validation. This study presents for the first time the analysis of plant-based food materials by using TD-DART-MS, and it has been demonstrated as a simple and high-throughput method for classification studies.

Plant-Based Food By-Products: Prospects for Valorisation in Functional Bread Development

The industrial and small-scale processing of plant-based food materials is associated with by-products that may have a negative impact on the environment but could add value to bread-based products. The bioactivity of plant-based food by-products, their impact on the properties of functional bread, and their bioavailability/bioaccessibility leading to potential health effects when consumed was reviewed. Plant-based food by-products which may be added to bread include rice bran, wheat bran, corn bran, grape pomace/seed extract, tomato seed/skin, and artichoke stems/leaves. These by-products contain high concentrations of bioactive compounds, including phenolics, bioactive peptides, and arabinoxylan. Pre-treatment procedures, including fermentation and thermal processing, impact the properties of plant-based by-products. In most cases, bread formulated with flour from plant-based by-products demonstrated increased fibre and bioactive compound contents. In terms of the sensory and nutritional acceptability of bread, formulations with an average of 5% flour from plant-based by-products produced bread with acceptable sensory properties. Bread enriched with plant-based by-products demonstrated enhanced bioavailability and bioaccessibility and favourable bioactive properties in human blood, although long-term studies are warranted. There is a need to investigate the bioactive properties of other underutilised plant-based by-products and their potential application in bread as a sustainable approach towards improving food and nutrition security.

Characterisation of mechanical properties of food materials during drying using nanoindentation

The microstructure of plant-based food materials (PBFM) is mostly composed of assemblies of irregular cellular compartments. Dynamically changing mechanical properties play a vital role in the drying kinetics, deformation, and the quality attributes of PBFM. Therefore, understanding the micro-level mechanical properties and their relationships with the moisture loss during food drying is essential. However, research on this filed has rarely been attempted. This research aims to investigate the micro-level mechanical properties of PBFM during drying and establish a set of relationships between the elastic modulus, hardness, and stiffness and the moisture content. Nanoindentation experiments were performed using Hysitron TI-950 TriboIndenter at different stages of drying. It was found that the mechanical properties remained quite steady at early stages of drying, which were significantly increased at the later stages of drying. This study established the essential relationships among different micro-mechanical properties of PBFM and moisture content during drying.

Effect of sample rugged surface on energy consumption and quality of plant-based food materials in convective drying

Drying is a simultaneous heat and mass transfer process aiming to remove water in order to extend the shelf life of food. However, food drying is very energy-intensive and time-consuming process and results in quality deterioration throughout drying. Energy requirement and the degree of quality degradation strongly depends on drying conditions. Although many studies investigated the effect of sample shape and size on drying kinetics and quality changes, there is no reported investigation on the effect of rugged surface or surface waviness on energy consumption and quality of food. In this study, relationships between sample corrugation and energy requirements and food in quality during drying have been investigated. The pattern of deformation and changes in esthetic appearance have also been investigated in this study. It was found that the amount of energy required during drying of brinjal, carrot, and radish varied significantly with the variation of sample shape. The minimum energy was required for drying samples with rugged surfaces; whereas the plane slice samples consumed higher energy. Similarly, changes in product quality attributes such as shrinkage, deformation and color were also different for these two types of samples.

Isothermal drying of plant-based food material: An approach using 2D polydimethylsiloxane (PDMS) micromodels

The aims of this study were to build PDMS micromodels that simulated plant-based food material, and use them to investigate the drying mechanisms at pore-scale, the drying front morphologies and the drying curves during the isothermal drying process. Micromodels were built using a modified photolithographic technique. Three normal pore size distribution functions were developed to simulate the plasmodesma, intercellular space, and cell wall. Micromodels were impregnated with a pyranine aqueous solution and placed on a balance illuminated with ultraviolet light. Isothermal drying was developed by natural convection (20 °C). Drying front morphologies displayed a hierarchical behavior in which pores with the largest diameter dried first. Drainage and surface evaporation sequences and internal evaporation controlled the drying of PDMS micromodels. The micromodels were useful to simulate plant-based food material and study isothermal drying of such porous media. The results led to the proposal of some drying mechanisms that were involved.

Novel Affordable, Reliable and Efficient Technologies to Help Addressing the Water-Energy-Food Nexus

Improving the food system sustainability and security is becoming an urgent global challenge. In this regard, one of the most effective routes is the shift of the human diet toward healthier and more sustainable consumption, involving in particular the prevalence of plant-based raw food materials. Controlled hydrodynamic cavitation (HC) technologies could help considerably in this transition. HC techniques are gaining increased scientific interest, and are quickly spreading across a wide range of technical fields, recently showing surprising performances with biological raw materials related to the food, agricultural and forestry sectors and resources. HC processes enjoy recognized advantages in the acceleration of the processing steps of plant-based food, the extraction of valuable bioactive compounds, the reduction and the valorization of waste streams, as well as the superior efficiency in resource use, energy consumption, process yield, and exergy balance than competing processes. Thus, HC is very promising candidate to help addressing the water-energy-food nexus, and, ultimately, sustainability. Findings obtained from direct experimental trials and recent literature concerning the applications of HC to food processing, provide a strong basis for novel investigation aimed at standardization, starting from the identification of the most suitable devices and the optimal processing parameters, eventually oriented to further spreading of HC applications.

Recent advances in micro-level experimental investigation in food drying technology

Food materials, particularly plant-based food materials, are mostly cellular in structure with diverse structural heterogeneities and variable cellular properties. To uncover the fundamental drying process, the cellular-level understanding of simultaneous heat and mass transfer process and associated morphological changes is essential. Consequently, researchers have attempted to investigate microlevel transport and material properties and their spatial and temporal distribution using recent innovative and cutting-edge experimental methods and technologies. The aim of this paper is to review the latest experimental technologies that can be applied to investigate the micro-level features of food material during drying. A comprehensive overview of advanced experimental techniques including X-ray microtomography, nuclear magnetic resonance (NMR), Near Infrared (NIR) Spectroscopy, light microscopy, nanoindentation and atomic force microscopy (AFM) has been presented. Finally, a summary of the current challenges of micro-level investigation for food drying is presented at the end of this paper.

Effect of hysteresis phenomena of cellular plant-based food materials on convection drying kinetics

Water removal rate during drying depends on the microstructural pathways of water migration from inside the food materials. The water removal rate also depends on the mechanical properties of plant tissue. There is no literature that shows the interrelationship between viscoelastic property and transport phenomena during drying. In this study, the influence of viscoelastic property of plant-based food material on transport phenomena during drying has been experimentally investigated. Granny Smith apple, pears, and beet root has been taken as the sample in this study. A 2 kN Instron universal testing machine and ImageJ software were used in order to measure and analyze the viscoelasticity of the samples. Three different fruits Granny Smith apple, pears, and beet root show different viscoelastic properties along with different energy loss due to hysteresis. A positive relationship was found between energy loss due to viscoelastic nature of materials and drying kinetics. This correlation can be explained by the nature of the cell wall stiffness that facilitates or hinders the water migration in mechanical and thermal energy applications.

A micro-level transport model for plant-based food materials during drying

Microscale transport phenomena govern the overall transport mechanism during drying of plant-based food material. However, there is limited research available that considers micro-level transport phenomena during drying. The primary goal of this work is to develop a microscale drying model based on the heterogeneous microstructure of the plant-based food materials to predict cellular-level water transport mechanism during drying. The microstructure, which was used as a heterogenous computational domain for the model, was developed from scanning electron microscope images of food samples. Simulation results show that moisture transport and distribution are significantly affected by the characteristics of cells, the intercellular spaces and the cell walls. The predicted moisture profile from the developed model was compared with results obtained by X-ray microtomography (µCT), and a good agreement was found. The model and the experimental results also confirmed that a water gradient (2–3%) still existed in the dried sample around the walls of the cells that are located at the centre of the tissue. The micro-level temperature distribution in the cells and intercellular spaces was also successfully predicted. It was found that the air-filled intercellular spaces were heated faster than the cells during drying. Sensitivity studies were performed to investigate the influence of the key drying parameters on the micro-level transport process. The developed model accurately reflects the micro-level transport phenomena that occur during drying.

Non-destructive investigation of cellular level moisture distribution and morphological changes during drying of a plant-based food material

This study investigates the complex microstructural changes and cell-level water transportation in plant-based food materials during drying, using X-ray micro-computed tomography (X-ray μCT). The investigations were performed on apple tissue to uncover the cellular level moisture distribution and the structural changes during convective drying at 50 °C, 60 °C, and 70 °C. Image analysis revealed that significant changes occurred in moisture content, and cell and pore size distribution with drying time and temperature. The moisture content determined using the X-ray μCT images was compared with that determined by the electronic moisture analyser (EMA) and good agreement was found. The results show a strong relationship between drying temperature, pore formation and deformation of the food material. At high drying temperature, the pore formation increased, which led to reduced shrinkage of the food material. The porosity of a sample of dried apple increased by 35% as drying temperature increased from 50 °C to 70 °C. However, a significant amount of cell rupture was observed during drying at the higher temperature. The cellular level moisture distribution profile confirmed that a traceable amount of water was still present in the centre cells of the tissue although the sample was deemed dried from the bulk moisture analysis. The findings of this study substantially enhance our understanding of instantaneous cellular level moisture distribution in a food sample over the time of drying.

Development of realistic food microstructure considering the structural heterogeneity of cells and intercellular space

Abstract The geometric characterization of the microstructure is required to model the micro level transport process inside the plant-based food material during thermal processing. However, the existing geometric construction methods are unable to consider the distinctive geometrical characteristics of cells and intercellular spaces during generation of the virtual microstructure. The main aim of this study is to develop a new method to build microstructure of the plant-based food materials with clear identification of cell and intercellular spaces. Granny smith and red delicious apple were taken as samples to implement and validate the proposed method. The virtual microstructure was generated from the scanning electron microscope image (SEM) of the apples. A new algorithm was developed based on the modified ellipse fitting method to generate the microstructure from microscopic images. Linear Discriminant Analysis (LDA) was used to classify the cells and the intercellular spaces. Statistical analysis was performed between the developed geometrical model and microscopic image to determine the accuracy of the proposed method. The area distribution of the microstructural model found in this study is significantly better than that found in the literature.