JELLY FOOD CONCENTRATE WITH ENCAPSULATED HIBISCUS EXTRACT

Background. Taking into consideration the intense rhythm of life, the development of technologies for instant food products of increased nutritional value is urgent. Typically, food concentrates for desserts include fruit or fruit and berry fillings and require cooking to prepare ready-made meals. In this case, heat treatment of the mixture (boiling) negatively affects the thermolabile biologically active compounds. The aim of the work was to develop a recipe for instant food jelly concentrates of increased nutritional value based on encapsulated powdery hibiscus extract. Materials and methods. To encapsulate the aqueous-alcoholic extract of hibiscus and obtain a powdered semi-finished product, swelling potato starch was used. Rheological studies were carried out using a "REOTEST-2" rotational viscometer. Results. In order to enrich food concentrates of instant kissel with biologically active substances, we studied a method for extracting dry hibiscus flowers with aqueous-alcoholic solutions of various concentrations. It was found that the extractivity and the transfer of polyphenolic compounds, including anthocyanins, to the extract are improved when a water-alcohol mixture with an ethyl alcohol concentration of 30 % is used as an extractant. For the preparation of a powdery hibiscus extract, modified swelling starch was used, which has the property of swelling in cold water, which makes it possible not to subject the mixture to prolonged heat treatment for preparing a ready-made dish and to preserve the biologically active substances of the hibiscus extract. In addition, this starch is an effective solid carrier that plays a protective role for thermolabile vitamins and bioflavonoids. On the basis of experimental studies, formulations of instant jelly have been developed, which include fructose, powdered hibiscus extract, apple pectin and ascorbic acid. The study of the rheological properties of semi-finished products based on hibiscus extract, as well as ready-made jelly, testifies to the receipt of a finished dessert with a delicate creamy consistency. Conclusion. A method for obtaining a powdery encapsulated hibiscus extract based on swelling potato starch and a composition of a food jelly concentrate using this semi-finished product have been developed. It was found that for the extraction of raw materials it is better to use a water-alcohol mixture with an ethanol content of 30 %, since most of the anthocyanins are converted into the extract under these conditions. The developed semi-finished product of dry hibiscus extract can be used as a thickener, acidifier and colorant in recipes for food concentrates for instant dessert dishes. Due to the use of swelling starch, food concentrates of jelly do not need to be boiled, and the presence of vitamins, organic acids, flavonoids and especially anthocyanins in the hibiscus extract increases the nutritional value of the finished product.

Catalytic Reduction of Graphene Oxide Membranes and Water Selective Channel Formation in Water–Alcohol Separations

Graphene oxide (GO) is a promising membrane system for chemical separation applications due to its 2-D nanofluidics properties and an ability to control interplanar spacing for selectivity. The permeance of water, methanol (MeOH) and isopropyl alcohol (IPA) through 5 µm thick membranes was found to be 0.38 ± 0.15, 0.33 ± 0.16 and 0.42 ± 0.31 LMH/bar (liter/m2·h·bar), respectively. Interestingly, the permeance of a water–alcohol mixture was found to be dramatically lower (~0.01 LMH/bar) than any of its components. Upon removing the solvent mixture, the transmembrane flux of the pure solvent was recovered to near the original permeance. The interlayer space of a dried GO membrane was found to be 8.52 Å, which increased to 12.19 Å. 13.26 Å and 16.20 Å upon addition of water, MeOH and IPA. A decrease in d-space, about 2 Å, was consistently observed when adding alcohol to water wetted GO membrane and an optical color change and reduction in permeance. A newly proposed mechanism of a partial reduction of GO through a catalytic reaction with the water–alcohol mixture is consistent with experimental observations.

PURIFICATION OF WATER-ALCOHOLIC MIXTURE WITH MODIFIED NATURAL MATERIALS

The aryticle presents the results of theoretical and experimental research on improving the technology of purification of water-alcohol mixture with natural modified minerals for the production of vodka. The methods and main filtering materials used in alcohol technology have been considered, the inefluence of natural efficiencies of modilification has been determined. Methods for determining physicochemical parameters, cationic-anionic composition of the sort, method of modification of natural obsidian and natural zeolite clinoptilolite are described. The paper presents the main unit specific costs of hydrochloric acid solution for removal from the surface of ash elements and limestone inclusions, drinking water and prepared for washing material, water-alcohol mixture to establish an equilibrium strength value to prevent dilution of the sort. The influence of modified natural materials on physicochemical parameters and cationic-anionic composition of sorting before and after its purification by modified obsidian and clinoptilolite in comparison with quartz sand is shown. Achieving a positive effect of cleaning and improving the transparency of sorting in the technology of filtration with modified natural minerals. The predicted resistance to changes in the physical and chemical parameters of the sorting after its aging in critical conditions and the control sample and the array of parameter stock to the critical limit is determined. It was found that filtering the sort with modified obsidian allows to increase the shelf life by two months, modified clinoptilolite - by 4 months. Modification of natural obsidian and clinoptilodite allows for reduced specific consumption of hydrochloric acid and prepared water in preparation for the main cycle to increase filtration efficiency by 10-15% and get vodka with higher transparency by 0,1-0,2 units and improve the microcomponent composition of the finished vodka