Plant oils contain a high content of unsaturated fatty acids. Studies of food products have revealed a considerable disproportion in the ratio of ω6 to ω3. This article presents information on the healthful qualities of eight new oil blends that contain a beneficial proportion of ω6 to ω3 fatty acids (5:1), as well as their degradation during heating at 170 and 200 °C. The fatty acid profile was analyzed by gas chromatography (GC), content of polar compounds and polymers of triacylglycerols by liquid chromatography (LC), water content was measured by the Karl Fischer method, and oxidative stability was measured by differential scanning calorimetry (DSC) and low-field nuclear magnetic resonance (LF NMR) methods. The results showed that during heating, the polar fraction content increased in samples heated at both analyzed temperatures compared to unheated oils. This was mainly due to the polymerization of triacylglycerols forming dimers. In some samples that were heated, particularly those heated to 200 °C, trimers were detected, however, even with the changes that were observed, the polar fraction content of the blends did not go beyond the limit. Despite the high content of unsaturated fatty acids, the analyzed blends of oils are characterized by high oxidative stability, confirmed by thermoanalytical and nuclear magnetic resonance methods. The high nutritional value as well as the oxidative stability of the developed oil blends allow them to be used in the production of food, in particular products that ensure an adequate supply of ω3 fatty acids.

Vegetable oils rich in polyunsaturated fatty acids are a valuable component of the human diet. Properly composed oil blends are characterized by a 5:1 ratio of ω6/ω3 fatty acids, which is favorable from a nutritional point of view. Unfortunately, their composition makes them difficult to use in food production, as they are susceptible to oxidation and are often characterized by a strong smell. Encapsulation in yeast cells is a possible solution to these problems. This paper is a report on the use of native and autolyzed yeast in the encapsulation of oils. The fatty acid profile, encapsulation efficiency, morphology of the capsules obtained, and thermal behavior were assessed. Fourier transform infrared analysis and low-field nuclear magnetic resonance relaxation time measurements were also performed. The process of yeast autolysis changed the structure of the yeast cell membranes and improved the loading capacity. Lower encapsulation yield was recorded for capsules made from native yeast; the autolysis process significantly increased the value of this parameter. It was observed that NY-based YBMCs are characterized by a high degree of aggregation, which may adversely affect their stability. The average size of the AY capsules for each of the three oil blends was two times smaller than the NY-based capsules. The encapsulation of oils in yeast cells, especially those subjected to the autolysis process, ensured better oxidative stability, as determined by DSC, compared to fresh blends of vegetable oils. From LF NMR analysis of the relaxation times, it was shown that the encapsulation process affects both spin-lattice T₁ and spin-spin T₂* relaxation times. The T₁ time values of the YBMCs decreased relative to the yeast empty cells, and the T₂* time was significantly extended. On the basis of the obtained results, it has been proven that highly unsaturated oils can be used as an ingredient in the preparation of functional food via protection through yeast cell encapsulation.

The aim of this study was to determine the peroxide values, acid numbers, oxidative stability (Rancimat method), antioxidant activity (DPPH method), antimicrobial activity (disc diffusion method), sensory properties (9-point hedonic scale), and fatty acid profiles (FAME) of five edible oils purchased from local Slovakian producers—grape seed oil, flax seed oil, walnut oil, poppy seed oil, and milk thistle seed oil. The peroxide value ranged from 2.27 (milk thistle oil) to 8.51 (flax seed oil) mmol O₂/kg. All these values were in accordance with regulations (upper limit of 20 mmol O₂/kg). The values of the acid number ranged from 0.11 (walnut oil) to 2.49 (milk thistle oil) mg KOH/g, and were in accordance with regulations as they did not exceed the value of 4 mg KOH/g. The oxidation stability was the lowest in flax seed oil (0.18 h) and the highest in grape seed oil (2.05 h). In milk thistle oil, the highest amounts of oleic and behenic acids, in flax seed oil, the highest amount of α-linolenic acid, and in grape seed oil, the highest amount of linolic acid were determined. Antioxidant activity was the strongest in the sample of grape seed oil—65.53 mg TEAC/L (Trolox equivalent antioxidant capacity). Samples of flax seed oil showed the strongest inhibition of Candida albicans CCM 8186 (4.58 mm) and Bacillus subtilis CCM 2010 (0.31 mm). Poppy seed oil was determined to be the most inhibiting towards Klebsiella pneumoniae CCM 2318 (3.68 mm). Milk thistle oil showed the strongest inhibition of Clostridium perfringens CCM 4435 (6.31 mm). Grape seed oil was the most inhibitory towards Staphylococcus aureus subs. aureus CCM 2461 (5.32 mm). Walnut oil showed the strongest activity towards Yersinia enterocolitica CCM 5671 (6.33 mm). The sensory analysis resulted in the samples of walnut and grape seed oil being awarded the highest scores for smell, taste, and overall acceptability. The tested edible oils are rich in biologically active compounds with antioxidant and antimicrobial activities. Their consumption can have a positive effect on the functioning of the human body and its health. Proper storage conditions are, however, necessary because of the susceptibility of these oils to oxidation.

The aim of this work was to assess the physical properties of Langmuir monolayers of three new oil blends “RBWg” (obtained by mixing rapeseed oil, black cumin oil, and wheat germ oil), “REp” (rapeseed oil and evening primrose oil), and “CRb” (camelina oil and rice bran oil), as well as to characterize the molecular dynamics of their protons using low-field nuclear magnetic resonance (LF NMR) method. The studied blends are rich in oleic acid (C18:1), linolenic acid (C18:2), and α-linolenic acid (18:3). The chromatographically determined ratio of n6 to n3 fatty acids was found to be in the range of 5.18–5.27. The appropriate n6/n3 fatty acid ratio was also confirmed by FT-IR analysis. The spin–lattice relaxation rate (R ₁) and spin–spin relaxation time (R ₂) measured by LF NMR method were similar for the RBWg and REp blends but different from the third oil blend (CRb), which indicates lower proton mobility in CRb. The observed changes in the properties of monolayers of oil blends suggest that the refined rice bran oil in the CRb blend also significantly changes the viscoelastic properties of this blend. The results obtained in this study provide a theoretical basis for the development of a well-balanced approach to using oils in food production technology.

The retrogradation of starch strongly influences the texture and stability of starchy foods. This study applied low-field nuclear magnetic resonance (LF NMR) to examine the effect of buckwheat hull (BH) fiber and green barley (GB) on water dynamics in normal (NPS) and waxy (WPS) potato starch gels. Relaxation times (T₁, T₂) and mean correlation times (τ_c) were monitored during 15 days of storage to evaluate changes in water mobility and starch–polymer interactions. Results showed that WPS, with its high amylopectin content, retrograded earlier than NPS. The addition of BH inhibited conformational changes associated with water binding in WPS gels, indicating that insoluble fiber entrapped water within the amylopectin network. Conversely, GB promoted higher τ_c values in WPS, reflecting enhanced ordering and reduced water mobility, while its impact on NPS was minor. In NPS systems, BH decreased τ_c, suggesting disruption of amylose-driven structural reorganization. These findings demonstrate that BH and GB exert opposite effects on starch retrogradation and highlight their potential as functional additives for tailoring texture and stability in starch-based food systems.

The aim of this study was to develop yeast-based microcapsules (YBMCs) containing vegetable oil blends with n3/n6 fatty acids in a ratio of 5:1. The oil blends, as well as YBMCs with these oils, were analyzed in nitrogen and oxygen. The shape and course of the TG and DTG curves were observed for yeast cells with all types of oil blends. No differences were observed in shape because of the microencapsulation curves with all oil blends between YMBCs prepared using native and autolyzed yeast. The results show that the yeast cells could be used as efficient microcarriers for the encapsulation of cold-pressed oils in order to provide thermal stable ingredients for the food industry.