Вестник МГТУ. 2018, №3.

Талейсник М. А. и др. Технология мучных кондитерских изделий с использованием эмульсии… 506 Materials and methods The study objects were experimental samples of emulsions for sugar cookies and samples of sugar cookies with optimized structural-mechanical and organoleptic characteristics. Physicochemical and organoleptic parameters of emulsion and biscuits were determined using standard methods. Organoleptic indicators were examined in accordance with GOST (All Union State Standard) 24901-89 and GOST 5897-90 1 ; mass fraction of moisture – by the sample drying in the drying chamber according to GOST 5900-73 2 ; mass fraction of fat – by the extraction-weight method according to GOST 31902-2012 3 ; biscuit absorptivity – in terms of mass increase in the product when immersed in the water at the temperature of 20 °C for a certain time (2 minutes) – according to GOST 10114-80 4 . Absorptivity depends on the products porosity and is characterized by the items mass ratio after wetting to the mass of dry products, which is expressed as a percentage. The water activity was determined with AquaLab 4TE analyzer (Decagon Devices, USA) using the mirror-cooled dew point sensor method; rheological characteristics of the emulsion (effective viscosity) was determined by the rotational viscometer Rheotest-2; plastic strength of the cookies – with the KP-3 tool belonging to Professor Volarovich. Results and discussion The quality of flour confectionery products largely depends on how the semi-finished products and dough are prepared. The processes of obtaining emulsions are among the most important fundamentals of the present day food industry. The use of cavitation effect is one of the most promising ways for forming stable emulsions in the presence of high productivity technical means [13]. There are two types of cavitation: acoustic cavitation occurs in a liquid medium during the passage of a high intensity sound wave; hydrodynamic cavitation takes place due to a sharp local decrease in the fluid pressure as a result of high flow velocities [13–14]. Industrial use of cavitation mixers has shown that they allow to exponentially intensify the mixing processes [4], and the physical phenomena associated with cavitation cause a number of effects (Table 1). Table 1. Effects caused by cavitation Таблица 1. Эффекты, вызванные кавитацией Effects Reason • Destruction and dispersion of solids; Caused by shocks (short-term pressure pulses) that arise when the bubbles collapse and the microflows appear beside them • Emulsification of immiscible products (emulsions); • Homogenization of the processed product; • Surface cleaning • Initiation and acceleration of chemical reactions Caused by ionization of gas during the formation of cavitation bubbles For the practical implementation of ultrasonic emulsification process, it is necessary to identify optimal exposure regimes and propagation conditions in order to create a uniform ultrasonic field in the mixture of two mutually insoluble liquids and to obtain emulsions with specified dispersion characteristics [13]. The initial stage of emulsion technology for sugar cookies is the stage of preliminary suspension preparation. VNIIKP has developed the basic scheme for suspension preparation in the three-step process [15–16] (Fig. 1). The three-stage method for the preparation of the suspension ensures high uniformity in the distribution of components throughout the volume and a marked decrease in the amount of undissolved solid phase particles and their size [16; 17] (Fig. 2). It is commonly known that suspensions are unstable systems and can be demixed with time. In order to increase their stability and dispersion, they were treated under cavitation conditions. The basic scheme of the emulsion preparation technology using cavitation processing is shown in Fig. 3. 1 GOST 24901-89. Biscuits. General specifications ; GOST 5897-90. Confectionery. Methods for determination of organoleptic quality indices, sizes, net-mass and components. 2 GOST 5900-73. Confectionery. Methods for determination of moisture and dry substances. 3 GOST 31902-2012. Confectionery. Methods of determination of fat weight fraction. 4 GOST 10114-80. Bisquits. Method for determination of swelling in water.