Plant-based food materials are porous and hygroscopic in nature; therefore, it contains three water environments, namely, intercellular, intracellular water and cell wall water. The intercellular water is known as capillary water or free water which is less constrained than intracellular water, considered as loosely bound water (LBW), and cell wall water, which is recognised as strongly bound (SBW). During food processing such as drying, frying, heating and cooking, optimisation of heat and mass transfer is crucial. The existing heat and mass transfer models for food processing are developed based on the concept that all of the water inside the food material is bulk water, which can act as free water that can be easily transported. This simplistic assumption has been made due to a lack of sufficient data to enable consideration of the proportion of free and bound water in plant-based food materials. Therefore, the aim of the present study is to investigate the proportion of different types of water such as free, LBW and SBW in 11 different plant-based food materials. The water proportion was investigated using 1H NMR T2 relaxometry. The experimental results uncovers that plant-based food materials contain about 80 to 92% LBW, 6 to 16% free water and only about 1 to 6% SBW. This investigation also confirms that among the five different fruits, kiwi contains the lowest percentage of LBW while Apple contains the highest percentage of LBW. Among the vegetables, eggplant comprises the largest amount of LBW while cucumber contains least amount of SBW. An attempt was made to establish a relationship between physical properties of fruits and vegetables and the proportion of the different types of water. Interestingly, it was found that SBW strongly depends on the proportion of solid in the sample tissue whereas FW depends on the porosity of the material.Food preservation is a major concern in today's world as about one-third of the global food production is lost annually due to lack of proper processing and preservation. Food processing is very energy intensive process and it consumes about 15–20% of energy used in industrial processes. Quality of processed food is also a big concern in the industries. Therefore energy efficiency and food quality are two major concerns in the food processing industry.The current food processing techniques such as drying are unable to ensure best quality and energy efficiency as many microlevel fundamentals of hygroscopic food material are unknown. One of the major unknown is the proportions and characteristics of different types of water inside the food materials and because of this an optimised food processing cannot be designed in order to ensure high quality and energy efficiency. The existing heat and mass transfer models are based on some simplistic assumptions, for instance all of the water inside the food material is considered bulk water; which means that it acts as free water that can be transported easily. This simplistic assumption has long been used due to lack of sufficient data to enable consideration of the proportion of free and bound water. Therefore, the aim of the present study is to determine the proportion of different types of water such as free water, loosely bound water (LBW) and strongly bound water (SBW) and establish relationship between physical properties and water characteristics in hygroscopic food materials.The findings of this study will enhance the understanding of plant-based food tissue that will contribute to a better understanding of potential changes occurring during food processing and will contribute to the development of accurate heat and mass transfer models and prediction of deformation. These findings will ultimately be significant for the equipment design engineers in food processing industry.

A thermal conductivity prediction regression equation was developed for four food materials as a single function of moisture content, porosity and initial thermal conductivity. It was assumed that temperature has a negligible effect on thermal conductivity. Thermal conductivity values of beef, apple, potato, pear and squid were used to develop the regression equation considering 122 points from the literature. The regression coefficient was 0.992. Squid gave the maximum mean per cent deviation of 11.89% (standard deviation 14-39). Potato gave minimum mean per cent deviation of 4.10% (standard deviation 1.74).

Water sorption isotherms and effective moisture diffusivities were determined at 20 degrees C for sponge cakes at high water activity as a function of their initial porosity, in the range 86 and 52% (0 g/g dry basis fat content), and of their fat content, ranging between 0 and 0.30 g/g dry basis (67% initial porosity). The equilibrium moisture values were not affected by food structure and decreased with increasing fat content. The effective moisture diffusivity decreased from 7.5 to 0.3 X 10(-10) m2/s with increasing moisture content from 0.30 to 2.20 g/g dry basis. Decreasing initial porosity from 86 to 52% decreased effective moisture diffusivity by more than four orders of magnitude. This behaviour was related to differences of water transfer mechanisms, with the contribution from liquid water diffusion in the solid matrix and from vapour water diffusion in pores. Increasing fat content of 0.30 g/g dry basis in sponge cake, independently of porosity, decreased effective moisture diffusivity by more than five orders of magnitude. A predictive mathematical model was used to simulate moisture intake in two-composite food systems: sponge cakes with varying initial porosities and fat contents and an agar gel as a model of a non-rate limiting water source. Increasing the density of the structure or addition of fat in the cereal-based phase could increase shelf life of composite foods.

Pharmaceutical and food pollutants have threatened global health. Pharmacotherapy has left a positive impression in the field of health and life of people and animals. However, the many unresolved problems brought along with residues of pharmaceuticals in the environmental and food. Consumption of the world's freshwater resources, toxic chemicals, air pollution, plastic waste directly affects water and soil resources. Pesticides have a wide role in pollutants. Therefore, the determination of pesticides is significant to eliminate their negative effects on living things. Nowadays, there are many analytical methods available. However, new analysis methods are still being researched due to certain limitations of traditional methods. Electrochemical sensors have drawn attention because of their superior properties, such as short analysis time, affordability, high sensitivity, and selectivity. The development of new analytical strategies for assessing risks from pharmaceutical to food pollutants in water and soil sources is important for the measurement of different pollutants. Moreover, the 2D-carbon nanomaterials used in the development of electrochemical sensors are widely utilized to enlarge the surface area, increase porosity, and make easy immobilization. Graphene (graphene derivations) and carbon nanotubes integrated nanosensors are widely used for the determination of pesticides. 2D-carbon nanomaterials can be tailored according to the purpose of the study. The characterization and synthesis methods of 2D-carbon nanomaterials are widely explained. Furthermore, enzyme nanobiosensors, especially Acetylcholinesterase (AChE), are widely used to determine pesticides. The three main topics are focused on in this review: 2D-carbon nanomaterials, pesticides that threaten life, and the application of 2D-carbon nanomaterials-based electrochemical sensors. The various developed 2D-carbon nanomaterials-based electrochemical sensors were applied in pharmaceutical forms, fruits, tap/lake water, beverages, and soils sources. This work aims to indicate the recently published paper related to pesticide analysis and highlight the importance of 2D-nanomaterials on sensors.

Few data are available on the thermophysical properties of high porosity foodstuff in the freezing domain. This paper presents some data obtained with a cellulose sponge used as a model food. The fraction of unfreezable water was obtained from differential scanning calorimetry data, using two different methods with a very good agreement. Water activity was experimentally determined at positive temperature. Experimental data were modeled by the Guggenheim-Anderson-de Boer (GAB) model, and a model deduced from the Clausius-Clapeyron equation. The GAB model was used to extrapolate these data in the subzero domain. It showed a good agreement until a water activity of 0.9, whereas the second model is usable only up to the value of 0.75.

Efficient extraction of polar sulfonamides antibiotics from aqueous samples and food is very challenging, because they are hydrophilic, their concentration is very low, and the matrix is complex. Covalent organic frameworks (COFs), a novel porous organic material, have attracted great attention. In this work, the spherical triphenylbenzene-dimethoxyterephthaldehyde-COFs (TPB-DMTP-COFs) were synthesized by a simple room temperature method, and due to their attractive properties, such as high outstanding acid-base stability, large specific surface area, low skeletal density, inherent porosity and high crystallinity, so TPB-DMTP-COFs as ideal solid phase extraction adsorbents showed excellent adsorption performance for trace polar sulfonamides in food and water. TPB-DMTP-COFs were characterized by scanning electron microscopy, Fourier-transform infrared spectroscopy, powder X-ray diffraction, and so on. The important parameters were optimized to improve the extraction efficiency of TPB-DMTP-COFs toward sulfonamides. Analysis of sulfonamides was performed by liquid chromatography–tandem mass spectrometry. The developed method based on TPB-DMTP-COFs material achieved low limits of detection (0.5–1.0 ng L⁻¹), wide linearity (5–1000 ng L⁻¹), and good repeatability (2.5%–8.7%). The possible extraction mechanism was also discussed. Finally, the method was successfully applied to the enrichment and detection of sulfonamides in environmental water samples and food samples. The present study indicated that TPB-DMTP-COFs had splendid prospects in highly sensitive analysis of other pollutants in complex matrix.