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In this work, pine and birch wood were modified by graphene oxide using a single vacuum impregnation method. The research results indicate that the impregnation of wood with graphene oxide increases the crystallinity of cellulose in both pine and birch wood, and the increase in crystallinity observed in the case of birch was more significant than in the case of pine. FT-IR analyses of pine samples impregnated with graphene oxide showed changes in intensity in the absorption bands of 400–600, 700–1500 cm−1, and 3200–3500 cm−1 and a peak separation of 1102 cm−1, which may indicate new C-O-C connections. In the case of birch, only some differences were noticed related to the vibrations of the OH group. The proposed modification also affects changes in the color of the wood surface, with earlywood containing more graphene oxide than latewood. Analysis of scanning electron microscope images revealed that graphene oxide adheres flat to the cell wall. Considering the differences in the anatomical structure of both wood species, the research showed a statistically significant difference in water absorption and retention of graphene oxide in wood cells. Graphene oxide does not block the flow of water in the wood, as evidenced by the absorbability of the working liquid at the level of 580–602 kg/m3, which corresponds to the value of pure water absorption by wood in the impregnation method using a single negative pressure. In this case, higher graphene oxide retention values were obtained for pine wood. [ABSTRACT FROM AUTHOR]

Fresh meat has a limited shelf life and is prone to spoilage. Drying serves as a common method for food preservation. Non-thermal techniques such as ultrasound treatment (US) can positively affect the drying processes and alter the final product. The study aimed to evaluate the impact of US pre-treatment on the hot air (HA) and freeze-drying (FD) of chicken breast meat and the quality of the dried products. US pre-treatment had a varied impact depending on the drying method used. The contact US method extended the HA drying time (about 50%) but improved water removal during FD (about 30%) compared to the untreated samples. Both methods resulted in low water content (<8.3%) and low water activity (<0.44). While rehydration properties (RR) and hygroscopicity (H) were not significantly affected by US pre-treatment in HA drying (about 1.35% and about 1.1, respectively), FD noticed differences due to shrinkage and porosity variations (RR: 2.4–3.2%, H: 1.19–1.25). The HA-dried samples exhibited notably greater tissue shrinkage and a darker surface color than the FD meat. Ultrasonic processing holds substantial potential in creating dried meat products with tailored characteristics. Hence, meticulous consideration of processing methods and parameters is of utmost importance. [ABSTRACT FROM AUTHOR]

The study aimed to determine the optimal parameters of the pulsed electric field as pre-treatment, and air temperature, in order to determine the sustainable production of dried apples with beneficial selected physical properties. A combination of PEF with energies of 1, 3.5, and 6 kJ/kg with hot-air drying at 60, 70, and 80 °C was used. The highest dry matter content was observed in tissue treated with PEF with an energy of 6 kJ/kg, and dried at a temperature of 80 °C. Both the drying and pre-treatment parameters influenced the change in the color of the dried material and the loss of dry matter during rehydration, but did not cause significant changes in the rehydration capacity and thermogravimetric properties (TGA). The novelty of investigations indicates that PEF treatment is capable of altering the quality of dried products. Nevertheless, the selection of particular drying temperatures has a more significant influence on the ultimate product quality. Therefore, choosing specific parameters for the treatment and drying process should be guided by the desired properties of the final product. PEF treatment is one of the most promising pre-treatments used before drying, and examining the possibility of its application to apples, which are one of the most frequently preserved fruits, will make an important contribution to the study of this field of science. [ABSTRACT FROM AUTHOR]

Entrapping bioactive ingredients like elderberry extract in hydrogels improves their stability and functionality in food matrices. This study assessed the effect of sequential thermal treatment with ultrasound (US) or high hydrostatic pressure (HHP) and treatment duration on pea protein–psyllium hydrogels as elderberry extract carriers. Measurements included color parameters, extract entrapment efficiency, physical stability, textural properties, microrheology, FT-IR, thermal degradation (TGA), SEM images, total polyphenols content, antioxidant activity, and reducing power. The control hydrogel was obtained using only thermal induction. Both treatments impacted physical stability by affecting biopolymer aggregate structures. Thermal and US combined induction resulted in hydrogels with noticeable color changes and reduced entrapment efficiency. Conversely, thermal and HHP-combined induction, especially with extended secondary treatment (10 min), enhanced hydrogel strength, uniformity, and extract entrapment efficiency (EE = 33% for P10). FT-IR and TGA indicated no chemical structural alterations post-treatment. Sequential thermal and HHP induction preserved polyphenol content, antioxidant activity (ABTS = 5.8 mg TE/g d.m.; DPPH = 11.1 mg TE/g d.m.), and reducing power (RP = 1.08 mg TE/g d.m.) due to the dense hydrogel structure effectively enclosing the elderberry extract. Sequential thermal and HHP induction was more effective in developing pea protein–psyllium hydrogels for elderberry extract entrapment. [ABSTRACT FROM AUTHOR]

The design of composites offers extensive opportunities for controlling parameters and utilizing diverse materials, including those sourced from recycling or waste streams. In this study, biocomposites were developed using high-density polyethylene (HDPE) and pomace derived from oilseed plants such as evening primrose, gold of pleasure, rapeseed, and sunflower seeds, mixed in a 1:1 ratio. These biocomposites were evaluated for their structural, mechanical, morphological, and thermal properties, as well as their vulnerability to overgrowth by cellulolytic fungi. The results indicate that incorporating plant waste into HDPE reduces thermal stability while increasing water absorption and thickness swelling. Additionally, the biocomposites showed enhanced fungal growth, which may improve their biodegradability. Notably, the PE_EP composite, derived from evening primrose pomace, did not show significant differences in surface roughness and MOE parameters compared to pure polyethylene. In the case of PE_R composite, an increase in MOE was observed while maintaining the MOR parameter compared to pure PE. Although generally the mechanical properties of composites were lower compared to pure polyethylene, the findings suggest that with further optimization, oil plant pomace can be a valuable raw material for producing biocomposites suitable for various industrial applications, thereby contributing to sustainability and effective waste recycling. [ABSTRACT FROM AUTHOR]

The growing world population necessitates the implementation of appropriate processing technologies for edible insects. The objective of this study was to examine the impact of distinct drying techniques, including convective drying at 70 °C (70CD) and 90 °C (90CD) and freeze-drying (FD), on the drying kinetics, physical characteristics (water activity, color), chemical characteristics (chemical composition, amino acid profile, oil properties, total polyphenol content and antioxidant activity, mineral composition, FTIR), and presence of hazards (allergens, microorganisms) of blanched yellow mealworm larvae. The freeze-drying process results in greater lightness and reduced moisture content and water activity. The study demonstrated that the freeze-dried insects exhibited lower contents of protein and essential amino acids as compared to the convective-dried insects. The lowest content of total polyphenols was found in the freeze-dried yellow mealworm larvae; however, the highest antioxidant activity was determined for those insects. Although the oil isolated from the freeze-dried insects exhibited the lowest acid and peroxide values, it proved to have the lowest PUFA content and oxidative stability. All the samples met the microbiological criteria for dried insects. The results of the study demonstrate that a high temperature during the CD method does not result in the anticipated undesirable changes. It appears that freeze-drying is not the optimal method for preserving the nutritional value of insects, particularly with regard to the quality of protein and oil. [ABSTRACT FROM AUTHOR]

Featured Application: Single-cell protein is a type of protein derived from fungi and it has gained attention as a meat substitute due to its high protein content, low fat content, and specific texture. However, this type of protein can be used in the development of functional foods as well as additive to high-protein products, protein bars, shakes, snacks, dairy alternatives, etc. In recent years, there has been an increasing demand for new sources of protein, both for human and animal nutrition. In addition to alternative sources of protein, such as algae or edible insects, protein obtained from yeast and mold biomass is becoming more and more important. The main fungal protein producers are the yeasts Saccharomyces cerevisiae, Kluyveromyces marxianus, Candida utilis, Yarrowia lipolytica, and the molds Fusarium venenatum, Aspergillus oryzae, and Monascus purpureus. The production of fungal protein has many advantages, including the ability to regulate the amino acid composition, high protein content in dry matter, the possibility of production in a continuous process, independence from climatic factors, and the possibility of using waste substrates as ingredients of media. One of the disadvantages is the high content of nucleic acids, which generates the need for additional purification procedures before use in food. However, a number of enzymatic, chemical, and physical methods have been developed to reduce the content of these compounds. The paper presents the current state of knowledge about fungal producers, production and purification methods, the global market, as well as opportunities and challenges for single-cell protein (SCP) production. [ABSTRACT FROM AUTHOR]

Featured Application: Consumers are becoming more conscious of how their eating habits influence their health, and they are more inclined to incorporate fruits and vegetables into their regular meals. In addition, they are exploring for novel raw materials with potential health benefits. Kiwiberry fruits include bioactive components such as vitamin C, carotenoids, chlorophylls, anthocyanins and phenolic acids, which contribute to their antioxidant activity. They also include lots of dietary fiber. However, they are seasonal and have a short shelf life. As a result, it is essential to adopt processing methods that ensure their availability at all times. To do this, they can be processed into a variety of products, including jams, juices, dry snacks and food powders, which can be used as components in a variety of other food and pharmaceutical items. The kiwiberry is an interesting source of bioactive compounds (micronutrients, polyphenols vitamins and pectins) and enzyme actinidine but has limited durability. The aim of this study was to determine the impact of shelf temperature (10 °C, 25 °C and 40 °C) during freeze drying on the foam-mat kiwiberry pulp drying process and the quality of the obtained material based on analyses such as moisture content, water activity, hygroscopicity, solubility, microstructure and spectral measurement using the FTIR method. The use of higher shelf temperatures during freeze drying positively influenced the drying process, reducing its duration by up to 40.7%. The shelf temperature caused changes in the dry matter content (97.2–99.6%), water activity (0.159–0.221), structure and hygroscopic properties (1.41–4.41 g water/100 g d.m.) of the kiwiberry foam mats. Foam-mat drying at 40 °C exhibited a significantly lower water activity, total porosity and hygroscopicity, providing properties favorable for good microbiological and functional stability during storage. Furthermore, this temperature applied during freeze drying resulted in an increase in the solubility of the obtained material, which indicates its possible use in the matrix of other food products. [ABSTRACT FROM AUTHOR]

Featured Application: A widely used method of food preservation is drying. Unfortunately, apart from the increase in the durability of the raw material and the decrease in its weight and volume, there are also negative changes related to its physical, chemical, and sensory properties. To reduce some unfavorable effects of the drying process, pretreatment can be used. Ultrasonic waves applied before drying in most cases positively affect the changes in food, obtaining high-quality products with changed physical properties. Additionally, ultrasounds have a positive impact on the efficiency of the technological process based on heat and mass transfer, reducing its duration, which results in lower production costs. Therefore, pretreatment using ultrasound is a promising alternative to the thermal pretreatment of raw materials. Beetroots are sources of bioactive compounds and valued pigments such as betalains. The purpose of this study was to determine the influence of ultrasound pretreatment on the beetroot infrared–hot air drying process and the functional properties of the obtained product. In this study, there were two used frequencies—21 and 35 kHz—and three different periods of time—10, 20, and 30 min. Since beetroots are usually subjected to thermal treatment, another aim was to examine the influence of blanching and soaking on the beetroot tissue properties in order to compare traditional and ultrasound-treated methods. As a result of this study, it was found that ultrasound pretreatment changed the dry matter content, water activity, thickness of the tissue, total color difference, and contents of betanin pigments in the beetroot. It was revealed that the drying process is shorter after ultrasound pretreatment using a 21 kHz frequency. Drying tissue exposed to ultrasounds showed a significant increase in the L* parameter; however, the decrease in the a* parameter was caused by a reduced content of betalain pigments. Taking into consideration parameters important from a technological point of view, it was found that the best condition for beetroot pretreatment is 20 min treatment, regardless of the frequency used. [ABSTRACT FROM AUTHOR]

Porous wood-based boards, like any lignocellulosic material, are susceptible to biocorrosion caused by mold fungi. Their durability can be extended by using biocides. Due to the fact that porous boards are considered an ecological material, it would be beneficial to also use natural agents to protect them. For this purpose, the surface of softboards was protected with a 30% solution of cinnamon bark oil in ethanol. Three application levels were used: 75 g/m2, 120 g/m2, and 200 g/m2 of solution. It has been shown that the cinnamon bark oil solution used at an application rate of 200 g/m2 is an effective fungicide, protecting softboards (SBs) against the development of mold fungi: T. viride and C. globosum. The dominant volatile component of cinnamon oil identified in the boards turned out to be cinnamaldehyde. Three months after treatment, this substance constituted 74% of the volatile components. The proposed treatment method allows for short-term preventive protection of boards against mold fungi. [ABSTRACT FROM AUTHOR]

In recent years, an increasing interest has been shown in alternative food sources. Many studies are focused on the use of insects. The aim of this study was to investigate the changes in the chemical and thermal properties of black soldier fly larvae influenced by the pulsed electric field (PEF) and convective (CD) or infrared–convective (IR-CD) drying techniques. Examinations of the basic chemical composition, properties of extracted fat (fatty acid composition, acid and peroxide values, and oxidative stability), total polyphenol content, antioxidant activity, allergen content, and thermogravimetric analysis (TGA) were performed. Generally, the results showed that dried black soldier fly larvae are a good source of protein and fat, up to 33% and 44%, respectively. The fat extracted from the dried insects consisted mainly of saturated fatty acids (above 75%), in particular lauric acid (C12:0). A good oxidative stability of the fat was also observed, especially from samples dried with the IR-CD method. The convective drying technique allowed for better preservation of protein content compared to samples dried with the IR-CD method. Nevertheless, samples treated with PEF were characterized by significantly lower protein content. The samples after PEF pretreatment, with an intensity of 20 and 40 kJ/kg and dried with the IR-CD method, were represented by a significantly higher total polyphenol content and antioxidant activity. Furthermore, in most cases, the convectively dried samples were characterized by a higher allergen content, both crustaceans and mollusks. Taking into account all of the investigated properties, it can be stated that the samples without treatment and those that were PEF-treated with an intensity of 40 kJ/kg and dried with the infrared–convective method (IR-CD) were the most rewarding from the nutritional point of view. [ABSTRACT FROM AUTHOR]

Vacuum impregnation (VI) stands as a diffusion-driven food processing method that has found recent application within the food industry, particularly for the cold formulation of fortified food products. Pulsed electric field (PEF) treatment can affect the food structure, influencing therefore the mass transfer phenomena during the further processing. Thus, the study aimed at investigating the effect of PEF treatment on selected physicochemical properties of vacuum-impregnated apples. Apple slices were vacuum impregnated with aloe vera juice solution with or PEF treatment at different intensities (125, 212.5 or 300 V/cm). The PEF was applied as a pretreatment—applied before the VI process as well as posttreatment—applied after the VI process. The VI process with aloe vera juice resulted in a sample weight increase of over 24% as well as structural changes, partial cell viability loss and color alteration. In addition, the decrease of bioactive compounds was observed, while antioxidant activity remained at a similar level as in raw material. PEF treatment adversely affected vacuum impregnation efficiency, causing microstructural changes and cell viability loss. Additionally, chemical composition modifications were evident through thermogravimetric analysis (TGA) and Fourier Infrared Spectroscopy (FTIR) analyses. Tissue hardness decreased significantly due to structural damage and caused high leakage from plant tissue, which resulted in hindering saturation with aloe vera juice during the VI process. Additionally, reduced bioactive substance content after PEF treatment was observed and the VI process did not restore apple samples of the bioactive compounds from aloe vera juice. [ABSTRACT FROM AUTHOR]

Food safety is a crucial aspect, when designing food packaging. It is necessary to assess every layer of the material that could be interacting with food. There are various substances that could be used to produce coatings for the cardboard materials, safe for the application in the food packaging materials. By introducing additional layer to the packaging material, it is possible to enhance food safety, improve packaging and food quality, and extend food shelf-life. The aim of this work is to present the background of some applications of paper coatings based on proteins, polysaccharides, lipids and others. Moreover the food safety aspect of paper and cardboard was described.

The study examined the effects of pulsed electric field treatment on the kinetics and properties of convective-dried mushrooms using different drying agents. Increasing the drying air temperature reduced drying time, while the use of dehumidified air resulted in faster water removal. PEF treatment, depending on the parameters, shortened the drying time maximum by 12% or extended the drying time. The physical (dry matter content, rehydration properties, hygroscopic properties, and color) and chemical (polyphenols content and anti-oxidant activity) properties were analyzed. The dry matter contents of the mushrooms were influenced by the drying temperature, while PEF pre-treatment did not influence the rehydration and hygroscopic properties in both cases of drying using air humidity. However, the color parameters were affected by the drying method and energy input, with higher energy input leading to decreased lightness, increased redness, and color saturation. The chemical analyses revealed that the anti-oxidant compounds in the dried mushrooms were influenced by various factors, with PEF treatment and drying non-dehumidified air polyphenol content increasing, whereas dehumidified air caused more phenolic degradation if it was combined with PEF treatment. Anti-oxidant activity varied depending on the drying agent, with non-dehumidified air generally exhibiting better properties. The highest total polyphenol content and best anti-oxidant properties were obtained for the PEF pre-treated with 3 kJ/kg of energy and dried with non-dehumidified air at a temperature of 70 °C. [ABSTRACT FROM AUTHOR]