An innovative form of the essential trace element copper for fortification of dairy products

Abstract

Microelementosis is a disease associated with a deficiency of certain vital microelements. Today, there are ways to combat the lack of essential micronutrients. In this article, the mechanochemical synthesis of a triple copper-containing complex with ascorbic acid and L-isoleucine, an essential amino acid, was carried out. Examination of the sample by X-ray diffractometry showed that the sample has a trigonal crystal structure with space group P31c. As a result of computer quantum chemical modeling, the values of the difference in total energy, chemical hardness, energy of the highest occupied molecular orbital and the lowest unoccupied molecular orbital were determined. We determined the optimal option for the interaction of copper with vitamin C and L-isoleucine, where the binding occurs through hydroxyl groups attached to the C2 and C3 atoms of ascorbic acid, and through the carboxyl group and α-amino group of isoleucine. The sample was examined by IR spectroscopy and confirmed by computer modeling data. The stability of the resulting complex was studied depending on the technological parameters — pH, temperature and exposure time. Using the Greco-Latin square method, a matrix for planning a multifactorial experiment was compiled. An analysis of the dependence of the change in optical density (∆ D) on pH, temperature and exposure time showed that the pH of the medium and the temperature of the solution have a significant effect on ∆ D: an increase in the pH of the medium and the temperature of the solution leads to an increase in ∆ D. Exposure time does not have a significant effect to change the optical density value (∆ D). The parameters at which sample stability is observed correspond to the lowest values of ∆ D: pH = 3–8, t = 25–70, τ = 5–15. The effect of the concentration of a copper-containing complex on the physicochemical parameters of milk was studied. It has been established that the optimal concentration of copper ascorbate isoleucinate for fortifying dairy products is 0.005 mol/l or less. Next, an organoleptic assessment of the indicators of milk enriched with copper ascorbate isoleucinate was carried out. The analysis of the results showed that the organoleptic parameters (smell and taste) of milk enriched with ascorbate-isoleucinate of copper are 0.1 points higher than those of milk enriched with the inorganic form of the essential trace element copper and 0.3 points lower than that of the control milk sample.