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A model for the structure of supported bilayer lipid membranes (s-BLM) is assumed based on the measurement of specific capacitance, electrostriction and surface potential of the s-BLM formed on the tip of freshly cut Teflon or polymer coated stainless steel wire and of the electrolyte-metal interface, depending on the frequency of AC voltage. We have shown that s-BLM does not represent a continuous bilayer on a metal support. Its structure is like that of a continuous monolayer, three layers, or in certain case, also like that of a bilayer interrupted by 'islands' of metal support. The former ones are characterized by a smaller resistance in comparison with a lipid bilayer and with specific capacitance 20-50 times higher than that of conventional, free standing BLM. The assumed model allows us to understand the nature of a number of effects observed on s-BLM, particularly the behavior of current fluctuations. The nature of current fluctuations can be easily explained by fluctuations of the size of the 'islands' both towards increase and/or decrease of their diameter due to removal and/or appearance of new lipid molecules on a metal support.

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The paper reviews and analyses the advantages and disadvantages of the existing technologies of drying shiitake mushrooms, which are a valuable source of bioactive polysaccharides, vitamins, antioxidants, etc. The findings presented in the paper show how various drying methods and their thermotechnological operating parameters affect the mechanostructural properties, chemical composition, content of aromatic substances and other compounds of mushrooms. It has been demonstrated that the traditional convection drying of shiitake in the temperature range 50–60°C allows maximum preservation of phenolic compounds, organic acids, nucleotides, sulphuric aromatic substances, and enhances the unique aroma of the mushroom. Radiation drying has such advantages as lower shrinkage of dried shiitake mushrooms, a higher coefficient of rehydration and higher hardness, and the drying time reduced by 66% compared with freeze-drying. Vacuum drying makes it possible to obtain high quality products, but significantly increases the duration of the process and reduces the content of aromatics. Radiation drying combined with hot air allows obtaining a dry form of shiitake rich in protein and bioactive polysaccharides and having high physicochemical properties, and reduces the duration of the process by 37.5% compared with convection drying. Spray drying of shiitake mushrooms is highly practical economically and allows organising industrial manufacture of high-quality dry mushroom powder in large volumes. It is characteristic of this drying method that its temperature effect on the product is slight, which makes it possible to preserve thermolabile bioactive substances. When using spray drying, it is advisable to add dextrin additives. This improves the structuring and moisture-conducting properties of the suspensions and their thermal stability, and helps preserve the unique aroma of shiitake mushrooms due to encapsulation of aromatic compounds. Studying the effect of various drying methods on the physicochemical properties of shiitake will lead to improving the existing technological processes and will make it possible to obtain products with desired properties.

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