Удосконалення технології жирових систем зі зниженим вмістом транс-ізомерів жирних кислот для маргаринів

Abstract

The thesis for a candidate of technical science degree by speciality 05.18.06 – technology of fats, essential oils and perfume-cosmetic products. – National Technical University "Kharkiv Polytechnic Institute", The Ministry of Education and Science of Ukraine, Kharkiv, 2019. In the dissertation the need of improvement of the production technology of fatty systems for margarines with minimal content of trans-isomers has been theoretically and experimentally substantiated and the necessary technological techniques for its implementation have been determined. Fatty systems are the integral part of human nutrition. Therefore, the modern demands for quality and safety require the improvement of the respective technologies for their production. The formed conjuncture of the foreign and domestic markets dictates the need to increase the production rate of major fat-and-oil products with high added cost, in particular margarines. Depending on the exclusion or introduction of a component in the formulation of the fatty product, its property is improved or significantly changed. The need to adjust the diet of modern humans in the direction of reducing the proportion of fats, which in their composition contain an excessive amount of trans-isomers of fatty acids, arises from the social effect of consumption of high quality fatty products and aims at improving the health of the population of Ukraine. The feasibility of reducing the content of trans-isomers in fatty systems is based on the proven relationship between the content of these isomers in the composition of fatty foods and the increased risk of cardiovascular disease, as well as diseases of metabolic disorders. In particular, the increased content of trans-isomers blocks the action of high density lipoproteins, initiating the deposition of cholesterol plaques on the walls of human blood vessels and provoking the development of atherosclerosis. The kinetics of the processes of biocatalytic interesterification and glycerolysis, on which the technology of production of fatty systems with reduced content of trans isomers is based, has been investigated. The basic regularities of kinetics of biocatalytic interesterification of triacylglycerols under the action of the enzymatic preparation Novozym 40086 and biocatalytic glycerolysis of triacylglycerols enriched with omega-3 polyunsaturated fatty acids have been determined using mathematical modeling. The rate constants of the forward and reverse reactions occurring in the reaction systems and the equilibrium constants of each of them have been determined. Based on the obtained data, the thermodynamic parameters have been calculated and conclusions have been made about the contribution of each of the reactions to the overall process as a whole. The results obtained will serve as the scientific basis for the determination of technological parameters for the production of fatty systems with a minimal content of trans-isomers. The regularities of the process of biocatalytic interesterification of fats under the influence of Novozym 40086 have been investigated and rational parameters of technology of production of fatty systems with reduced content of trans-isomers have been established. A mathematical model has been obtained, which allows to predict the solid phase content of biocatalytic interesterification products, which is one of the most important ways of estimating their consistency, based on data of the fat base composition. The developed model allows to solve the inverse problem – based on the target consistency of the fat product to find its formula. The possibility of improving the composition and properties of fat systems with reduced content of trans-isomers by fractionation of the product of biocatalytic interesterification has been shown. A mathematical model has been developed that allows to predict oleogels thermal stability based on the their component composition. The response surface methodology was applied, and the unknown values of the parameter vector have been determined by applying regression analysis algorithms. The analysis of the obtained dependences made it possible to conclude that the increase in the oleogel formulation of the content of beeswax from 0.30 to 3.30% of the mass. causes an increase in thermal stability. Further enhancement of the content of the specified component is not rational, as it practically does not affect the response. However, when varying the content of tripalmitin from 0.30 to 3.10% of the mass. there is an increase in thermal stability, and with a further increase – a decrease in this indicator. The rational values of the mass fractions of oleogel components have been determined: the content of beeswax is 3.27 wt%; the content of tripalmitin 3.07% of the mass. and the content of monoacylglycerols 4.70% wt. At these values, the maximum value of the coefficient of thermal stability is reached. It has been shown that the number of mesophilic aerobic and optional anaerobic microorganisms in soft margarines based on fatty systems with reduced content of trans-isomers during 60 days of storage was below the standard and were not higher than 3.4 · 103, i.e. more than an order of magnitude less than the norm. In addition, 0.01 g of the tested samples did not show CGB, and quantitative indicators of the presence of molds and yeast also did not exceed the norm. The process operational diagram for the production of soft margarines with reduced content of trans-isomers of fatty acids has been proposed. The scientific novelty of the obtained results is that for the first time: – the basic regularities of the course of biocatalytic processes underlying the technology of production of fat systems with reduced content of trans-isomers have been established; – rational parameters of biocatalytic interesterification of fats under the action of the enzyme preparation Novozym 40086 have been determined; – a mathematical model has been developed that allows to predict the content of the solid phase at different temperatures in the products of biocatalytic interesterification on the basis of data on the component composition of fatty raw materials; – quantitative dependences of thermal stability of oleogels on the formulation composition of their dispersed phase have been established. The practical significance of the results for the fat-and-oil industry consists in the developing of promising technology of fatty systems with reduced content of trans-isomers using products of biocatalytic reactions and oleogels. Formulations of emulsion products based on developed fat systems have been offered. The standard manual has been developed: TUU 10.4-02071180-087: 2019 for a new type of product – soft margarine "Novel" with extended shelf life. The results of the dissertation have been introduced into the educational process of the Department of Technology of Fats and Fermentation Products of the National Technical University "Kharkiv Polytechnic Institute".