During the last decade, research into genetic markers in the casein gene cluster has been actively introduced in cattle breeding programs. A special interest has been paid to the polymorphism of the CSN3 gene, responsible for the expression of the k-casein, playing a key role in protein coagulation, interaction with whey proteins, stabilization, and aggregation of casein micelles. This paper aimed to determine the effect of CSN3 genetic polymorphism on acid; rennet; acid–rennet; heat- and acid-induced as well as heat- and calcium-induced coagulation in skimmed milk; and protein-standardized milk systems (UF, NF, RO, VE). The influence of polymorphic variants of the CSN3 gene on the coagulation ability of milk proteins was assessed by the particle size of casein micelles, protein retention factor in the clot, and coagulation ability (duration of induction period, mass coagulation period, dynamic viscosity in gel point). The correlation between CSN3 gene polymorphism and protein coagulation was revealed. Milk systems obtained from CSN3 BB milk were found to have the shortest duration of coagulation, formation of better gel strength values, and increased yield compared to CSN3 AA. This study will improve the efficiency of milk processing and optimize the technology of dairy product production.

The development of molecular genetic and bioinformatic systems for identifying the species of milk and the raw material composition of dairy products is of great scientific and practical importance with the purpose of introducing developments in the system for controlling the turnover of falsified products. The aim of the research is to develop a method of PCR-RFLP analysis for species identification of milk and dairy products from agricultural ruminant animals by the κ-casein gene (CSN3) with the possibility of qualitative and relative quantitative assessment of species-specific DNA of the tested biomaterial. The objects of research were samples of raw milk and milk powder, pasteurized cream, and hard and semi-hard cheeses. The developed method of species identification of milk and dairy products includes sample preparation of the studied samples, nucleic acid extraction, combined PCR-RFLP technique, detection of obtained results by the method of horizontal electrophoresis in agarose gel and their analysis, including using the developed mathematical algorithms and software. The synergistic effect established in combined operation of 2 restriction enzymes ensured their application in a mix with increased performance in an ergonomic way in the context of DNA authentication of cow, goat, and sheep milk and dairy products based on them. The specificity and sensitivity of the proposed method is potentially suitable for implementing the development of a system to control the turnover of falsified and counterfeit goods.

Sweetened condensed milk (SCM) is a product widely used by both consumers and other food production branches. However, it contains a lot of sucrose. This study aimed to examine the effects provided by sugar substitutes, such as trehalose, isomaltulose, and polydextrose, upon the SCM sensory profile and valuable quality indicators, such as water activity, viscosity, acidity, crystals size, and Maillard reaction potential (browning index, color change, loss of free amino acids). The study was performed by making model systems of SCM (MSCMs) using the method of reconstitution of powdered ingredients. All the presented carbohydrate compositions in MSCMs provided Aw value typical of intermediate-moisture food, which contributes to the long-term shelf-life of the product. However, only 2 MSCMs with compositions consisted of isomaltulose, trehalose (22.55% and 22.55%); trehalose (28.19%), sucrose (5.64%), polydextrose (5.64%), isomaltulose (5.64%) showed the stability of Aw within 14-d storage period. Trehalose and polydextrose in MSCMs with mono-carbohydrate added fraction demonstrated their high structure-forming ability expressed in high values of dynamic viscosity (>30 Pa·s), provided not by crystallization. MSCMs containing trehalose in predominant amount in the carbohydrate compositions (≥50%) showed lower average crystal size (<16 μm) compared with other MSCMs with di- and tetra-carbohydrate added fractions with predominant amount of isomaltulose and polydextrose. Isomaltulose and polydextrose added to MSCMs led to pronounced browning, while trehalose and sucrose reduced this effect in MSCMs with di- and tetra-carbohydrate added fractions. Addition of 22.55% of polydextrose to carbohydrate fraction of MSCMs caused bitterness, while 5.64% didn't affect the taste. Based on the results of all the research conducted the most optimal carbohydrate compositions to produce SCM with lower calorie, sucrose contents and stable adequate values of processing and sensory properties were trehalose (22.55%) with isomaltulose (22.55%) and trehalose (28.19%) with sucrose (5.64%), polydextrose (5.64%), isomaltulose (5.64%).

DNA authentication of wines is a process of verifying their authenticity by genetic identification of the main plant component. The sample preparation of experimental and commercial wines was carried out by precipitation of wine debris by centrifugation with preliminary exposure with precipitators and co-precipitators, including developed macro- and micro-volume methods applicable to white or red wines, using polyvinylpyrrolidone as a co-precipitator. Addition of 2-mercaptoethanol and proteinase K to the lysing solution made it possible to adapt the technology for DNA extraction from the precipitated wine debris. The additionally tested technique of DNA extraction from wine debris by dimethyl sulfoxide (DMSO) lysis had fewer stages and, consequently, a lower risk of contamination. The results of further testing of one of the designed primer pairs (UFGT-F1 and UFGT-R1) in conjunction with the tested methods of wine material sample preparation and nucleic acid extraction, showed the advantage in the given set of oligonucleotides over previously used ones in terms of sensitivity, specificity and reproducibility. The developing strategy for genetic identification of grape varieties and DNA authentication of wines produced from them based on direct sequencing of polymerase chain reaction (PCR) products is implemented by interpreting the detected polymorphic positions of variable Vitis vinifera L. UFGT gene locus with distribution and split into 13 UFGT gene-associated groups.