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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]

Featured Application: The developed edible coatings and films can be used as an alternative to plastic packaging and additionally increase the attractiveness of the product. The use of an appropriate coating composition obtains high-quality freeze-dried vegetable bars. The aim of this study was to analyze the selected physical properties of vegetable bars coated with a coating based on pork gelatin (8% or 12%) with (25% or 50%) or without vegetable broth. The scope of work included developing the composition of edible coatings; preparing bars and coating freeze-dried vegetable bars; analyzing the water activity, dry matter content, the structure of vegetable bars based on microscopic analysis, and porosity; and then conducting a comparative analysis of the obtained results. The analyses show that the composition of the coating and the coating method influence the structure and selected physical properties of freeze-dried bars. Coating freeze-dried vegetable bars increases their water activity to the range of 0.215–0.389, and reduces their dry matter content to 93–96%. The porosity of the samples decreased (85–91%), but the use of coatings in the form of an edible film was more beneficial than immersing the dried material in a film-forming solution. The addition of vegetable broth to edible films improves the physical properties of the dried fruit and may additionally increase the taste of vegetable bars. [ABSTRACT FROM AUTHOR]

The study aimed to evaluate the effect of storage temperature on quality changes in freeze-dried carrot–orange–ginger (COG) snacks obtained with 2% of apple (AP) or blackcurrant (BP) pomace powder or 1.5% of pectin (LMP). The material was stored at 4, 25 and 40 °C for 1, 3, 6 and 12 months in pouches impermeable to vapour, oxygen and light. Water content and activity, texture, colour, total polyphenol content and antioxidant activity were examined to evaluate the products' quality. During storage, water content and activity fluctuations were noted, but no critical values were exceeded. Texture properties remained stable in snacks with pomace powders compared to those with pectin, the hardness of which significantly decreased when stored at ambient and elevated temperatures. However, the product with pectin was found to change colour the least over time. The results obtained for chemical properties were not clear, but they strongly indicated the occurrence of the transformation of some chemical compounds. Overall, a lowered temperature helped to maintain the quality of the freeze-dried snacks for the longest time. The presented research contributes to the general knowledge of the behaviour of innovative products with the addition of nonconventional but sustainable compounds, revealing the potential for quality and stability improvements. [ABSTRACT FROM AUTHOR]

Edible hydrogel coatings or films in comparison to conventional food packaging materials are characterized as thin layers obtained from biopolymers that can be applied or enveloped onto the surface of food products. The use of lipid-containing hydrogel packaging materials, primarily as edible protective coatings for food applications, is recognized for their excellent barrier capacity against water vapor during storage. With the high brittleness of waxes and the oxidation of different fats or oils, highly stable agents are desirable. Jojoba oil obtained from the jojoba shrub is an ester of long-chain fatty acids and monovalent, long-chain alcohols, which contains natural oxidants α, β, and δ tocopherols; therefore, it is resistant to oxidation and shows high thermal stability. The production of hydrogel films and coatings involves solvent evaporation, which may occur in ambient or controlled drying conditions. The study aimed to determine the effect of drying conditions (temperature from 20 to 70 °C and relative humidity from 30 to 70%) and jojoba oil addition at the concentrations of 0, 0.5, 1.0, 1.5, and 2.0% on the selected physical properties of hydrogel edible films based on whey protein isolate. Homogenization resulted in stable, film-forming emulsions with bimodal lipid droplet distribution and a particle size close to 3 and 45 µm. When higher drying temperatures were used, the drying time was much shorter (minimum 2 h for temperature of 70 °C and relative humidity of 30%) and a more compact structure, lower water content (12.00–13.68%), and better mechanical resistance (3.48–3.93 MPa) of hydrogel whey protein films were observed. The optimal conditions for drying hydrogel whey protein films are a temperature of 50 °C and an air humidity of 30% over 3 h. Increasing the content of jojoba oil caused noticeable color changes (total color difference increased from 2.00 to 2.43 at 20 °C and from 2.58 to 3.04 at 70 °C), improved mechanical elasticity (the highest at 60 °C from 48.4 to 101.1%), and reduced water vapor permeability (the highest at 70 °C from 9.00·10−10 to 6.35·10−10 g/m·s·Pa) of the analyzed films. The observations of scanning electron micrographs showed the heterogeneity of the film surface and irregular distribution of lipid droplets in the film matrix. [ABSTRACT FROM AUTHOR]

The aim of this work was to develop edible films derived from gelatin and beef broth and to analyze the physical properties of the output products. The presented research is important from the point of view of searching for food packaging solutions that may replace traditionally used plastic packaging. This study's conceptual framework is in line with the trend of sustainable development and zero waste. This study was conducted to develop a recipe for edible films derived from beef gelatin with gelatin concentrations at 4%, 8%, and 12% enriched with additions of beef broth in amounts of 25, 50, 75, and 100%. Selected physical properties of the output edible films were examined in terms of thickness, swelling in water, opacity, water content, water solubility, structure, and mechanical properties. The conducted research made it plausible to conclude that the addition of broth has a positive effect on the extensibility of the edible films and the other physical properties under consideration, especially on decreasing the film thickness, which was found to vary between 50.2 and 191.6 µm. When gelatin and broth were added at low concentrations, the tensile strength of the films increased, and subsequently decreased; however, an opposite effect was observed for elongation at break. The increased broth concentration caused the film opacity to increase from 0.39 to 4.54 A/mm and from 0.18 to 1.04 A/mm with gelatin concentrations of 4% and 12%, respectively. The water solubility of the gelatin films decreased as a result of the broth addition. However, it was noticed that increasing the content of broth caused the water solubility to increase in the tested films. The mere presence of broth in the gelatin films changed the microstructure of the films and also made them thinner. [ABSTRACT FROM AUTHOR]

The development of fruit-based products with a high proportion of fruit and good nutritional, sensory and functional properties may help to diversify market supply. These products ought to be attractive, especially to young people, easy to consume and have a reasonably long shelf life. Three recipes of freeze-dried strawberry jelly with low-methoxyl pectin (LMP) (2.0, 2.5, 3.5% LMP) with the use of strawberry pulp were obtained and physical properties were investigated to choose the sample with the best quality factors. The quantity of added low-methoxyl pectin influences the physical properties of freeze-dried strawberry jellies. The recipe with 2.5% addition of low-methoxyl pectin was chosen based on the results obtained. Despite the relatively high friability and low hardness, and higher shrinkage, it has a fast rate of rehydration. It is also characterised by high porosity and the parameters of the colour most similar to the raw material and low water content and activity.

The work aimed to investigate the rheological properties and the gelling process of selected film-forming solutions obtained based on hydrocolloids, such as sodium alginate, highly methylated pectin, and soy protein isolate with the addition of pumpkin purée. It was found that both concentration of hydrocolloid and the addition of pumpkin purée affected the rheological parameters. The non-linear nature of the flow curves was demonstrated, which allowed the curves to be described using the Ostwald de Waele model. The addition of pumpkin purée and the concentration of the structure-forming substance affected the apparent viscosity of the composite film-forming solutions. Considering the applied parameters, only the gelation temperature of composite gelatin film-forming solutions with the addition of pumpkin purée was possible to determine. Additionally, degassing of the solutions with the addition of pumpkin purée resulted in the reduction of the aeration degree and smoothening of the edible films' surface. [ABSTRACT FROM AUTHOR]

Highly methylated apple pectin (HMAP) and pork gelatin (PGEL) have been proposed as gelling agents for pumpkin purée-based films. Therefore, this research aimed to develop and evaluate the physiochemical properties of composite vegetable films. Granulometric analysis of film-forming solutions showed a bimodal particle size distribution, with two peaks near 25 µm and close to 100 µm in the volume distribution. The diameter D4.3, which is very sensitive to the presence of large particles, was only about 80 µm. Taking into account the possibility of creating a polymer matrix from pumpkin purée, its chemical characteristic was determined. The content of water-soluble pectin was about 0.2 g/100 g fresh mass, starch at the level of 5.5 g/100 g fresh mass, and protein at the level of about 1.4 g/100 g fresh mass. Glucose, fructose, and sucrose, the content of which ranged from about 1 to 1.4 g/100 g fresh mass, were responsible for the plasticizing effect of the purée. All of the tested composite films, based on selected hydrocolloids with the addition of pumpkin purée, were characterized by good mechanical strength, and the obtained parameters ranged from about 7 to over 10 MPa. Differential scanning calorimetry (DSC) analysis determined that the gelatin melting point ranged from over 57 to about 67 °C, depending on the hydrocolloid concentration. The modulated differential scanning calorimetry (MDSC) analysis results exhibited remarkably low glass transition temperature (Tg) values, ranging from −34.6 to −46.5 °C. These materials are not in a glassy state at room temperature (~25 °C). It was shown that the character of the pure components affected the phenomenon of water diffusion in the tested films, depending on the humidity of the surrounding environment. Gelatin-based films were more sensitive to water vapor than pectin ones, resulting in higher water uptake over time. The nature of the changes in water content as a function of its activity indicates that composite gelatin films, with the addition of pumpkin purée, are characterized by a greater ability to adsorb moisture from the surrounding environment compared to pectin films. In addition, it was observed that the nature of the changes in water vapor adsorption in the case of protein films is different in the first hours of adsorption than in the case of pectin films, and changes significantly after 10 h of the film staying in an environment with relative humidity RH = 75.3%. The obtained results showed that pumpkin purée is a valuable plant material, which can form continuous films with the addition of gelling agents; however, practical application as edible sheets or wraps for food products needs to be preceded with additional research on its stability and interactions between films and food ingredients. [ABSTRACT FROM AUTHOR]

The main research objective of the work was to demonstrate that the low-temperature sous-vide method allows obtaining a culinary product with selected physical, chemical, microbiological, and sensory properties that are more favorable compared to the corresponding features of the product obtained by conventional methods used in closed-type mass catering establishments, with the example of chicken breast. In addition, the aim was to demonstrate higher storage stability of culinary samples of chicken breast prepared by the sous-vide technique compared to samples prepared by conventional methods. The results confirm that the sous-vide method allows obtaining a product with the expected physical and chemical properties, comparable or even better with samples obtained by heat treatment methods, provided that high-quality raw materials and a high level of hygiene in the production process are used. Implementation of the innovative sous-vide method allows for extending the gastronomic offer of closed-type mass catering establishments with microbiologically safe dishes, desirable in sensory evaluation and stable during storage, which also allows for reducing the loss of prepared meals. [ABSTRACT FROM AUTHOR]

The influence of the structure formed by the type of hydrocolloids (low-methoxyl pectin, the mixture of xanthan gum, and locust bean gum, and mixture of xanthan gum, and guar gum) and the aeration time (3, 5, 7, and 9 min) on textural properties of freeze-dried gels were investigated. The hardest texture generating the strongest acoustic emission was obtained by freeze-dried pectin gel, characterised by the lowest porosity and the largest pore diameter. Aeration time significantly affected mechanical and acoustic properties of the pectin gel lyophilisate. No effect of gel aeration time on tested characteristics of samples with mixture of hydrocolloids was observed. Strong positive correlations between acoustic energy as well as the maximum force and work and negative ones between porosity and pore diameter indicate that greater resilience and stronger acoustic emission of freeze-dried gels was caused by the reduction of porosity and the increase in the pore size of the material. Practical applications The research is expected to show the phenomenon of structure formation when preparing and freeze-drying gels and explain the influence of the process parameters (time of aeration, the type of hydrocolloids) on the formation of the internal structure and physical properties of a dried product, especially mechanical and acoustic properties. This achievement will contribute to the development of the science of food and human nutrition, especially within the context of the popular research on aerated diet products. The expected result will be the ability to develop a new technology for producing food with a delicate texture, using the phenomenon of sublimation. As a result, designing changes in the structure of freeze-dried fruit gels with a delicate structure will be possible due to the choice of ingredients and aeration parameters in order to develop innovative food characterised by favorable nutritional, health and functional properties, which will be attractive for the consumers. [ABSTRACT FROM AUTHOR]