IntroductionFood production processes are organized in sucha way as to ensure the highest quality of the finishedproduct. During processing, raw materials of plantorigin are exposed to various mechanical stresses. Inthis regard, rheological analysis of food products isbecoming increasingly important for assessing thequality of raw materials and finished products, as wellas for predicting the behavior of semi-finished productsduring processing. In particular, it is used to determinethe structure of the product and its characteristics inaccordance with the technical regulations [1].Mayonnaise is a multicomponent, finely dispersedwater-fat emulsion of the direct oil-in-water type thatis stable over a wide temperature range [2–4]. In thisproduct, vegetable oil is an internal phase in the formof tiny drops in a dispersion medium [5].According to the standard, high-calorie mayonnaisemust contain more than 50% of edible vegetable oil,which forms its fat phase [6]. Mayonnaise is classifiedas a promising food product due to its compositionand sensory properties. Also, it is used as a seasoningfor various dishes. By enhancing the food’s nutritionalvalue and taste, mayonnaise stimulates appetite andimproves digestion. It is a product of high biologicaland physiological value [7].Vegetable oil is one of the main componentsof mayonnaise that contributes to its sensory andphysicomechanical properties [8]. The oil content hasa significant effect on the product’s rheological propertiessuch as yield strength, as well as storage and loss moduli.A combination of sunflower and pumpkin seed oilscan provide an optimal composition of fatty acids andtocopherols, natural antioxidants that improve nutritionaland sensory properties of mayonnaise. In particular,sunflower oil enriches the product with essential linoleicacid, while cold-pressed pumpkin oil is rich in oleic acidand gamma-tocopherol, contributing to longer shelf life.In addition, the latter’s aroma and color can enhancethe product’s sensory properties.Other main ingredients of mayonnaise are milk proteins,egg powder, stabilizers, and water. Fat-solublevitamins, sugar, salt, mustard, and various flavor additivesare present in small amounts [9].Powdered milk, egg powder, and vegetable phospholipidsare used as emulsifiers [10]. Powdered milkis also a structure-forming agent, since milk proteinsswell in the presence of moisture, increasing the waterretainingcapacity of mayonnaise [11].Mustard powder is used as a flavor additive, as wellas an emulsifier and a structure-forming agent due to itsproteins. Mustard powder should be dry, with a sharpsmell of allyl oil and a light yellow color. Mustardpaste should be free of mustiness and bitterness [12].Acetic acid improves the taste and enhancesbactericidal properties of mayonnaise. Water is neededto dissolve salt and sugar, as well as to dissolve andswell milk proteins and other ingredients.Vegetable oil contained in mayonnaise provides thehuman body with physiologically active (essential) fattyacids, which lower blood cholesterol and help preventatherosclerosis. Milk and egg powder are sources ofproteins and essential amino acids, while sugar is asource of carbohydrates. Organic acids (acetic and citric)improve digestion, provide the required acidity andbactericidal purity, and determine taste and aroma [11].Mayonnaise is a direct-type emulsion that is easilyabsorbed by the body. This fact and the content ofvegetable oil determine its nutritional value [14].Egg yolks act as emulsifiers mainly due to thepresence of phospholipids, as well as high and lowdensity lipoproteins. Vinegar, salt, sugar, and mustardare added to mayonnaise for flavor. These ingredientsplay an important role in the physical stability ofthe emulsion [15, 16]. Lutein, phycocyanin and othercompounds, as well as processed beets and fruitcomponents provide mayonnaise with oxidation stabilityand contribute to its taste and color, enhancingconsumer interest [10, 17–19]. Rheological propertiesare an important quality criterion for food products,including water-fat emulsions (mayonnaise, sauces, andmargarine) [20]. They are responsible for the product’sconsistency and quality during production, storage, andtransportation [21, 22]. The rheological characteristicsof mayonnaise are mainly determined by its fat phase,as well as thickeners, stabilizers, and emulsifiers inits formulation [23]. The product’s quality, stability,and viscosity depend on the homogenization process,the dispersion of fat droplets in the continuous waterphase, egg yolk, the type of carbohydrates, as well asthe amount and type of milk [24–27]. In this type ofemulsion, fat droplets are mechanically dispersed inthe continuous water phase of acetic acid, while naturalemulsifiers from egg yolk (phospholipids and proteins)ensure greater stabilization of the entire system [28].The homogenization parameters (rotor speed and time)and the choice of a rotor-stator system, which formsfat droplets of a larger or smaller diameter, determinethe medium’s stability and play an important role inthe formation of a water-fat emulsion [29–31].We aimed to study the rheological and texturalproperties of mayonnaise containing pumpkin and riceoils, as well as various types of honey. We also soughtto determine the influence of process parameters andthe composition of the oil phase on the rheologicalproperties of mayonnaise.Study objects and methodsHigh-calorie mayonnaise with pumpkin and rice oilswas formulated from refined sunflower oil, cold-pressedpumpkin seed oil, and refined rice oil (fat phase); eggproducts (fresh and pasteurized egg yolks and wholeegg powder); carbohydrates (glucose, fructose, lactose,742Bredikhin S.A. et al. Food Processing: Techniques and Technology. 2022;52(4):739–749sucrose, inulin HD); acetic acid; sea salt; mustard; dairyproducts (whole milk, skimmed milk, and whey powders);tartaric acid; distilled water; and banana puree (Table 1).Mayonnaise with the addition of honey was formulatedfrom refined sunflower oil (fat phase), egg yolk, honey,acetic acid, sea salt, tartaric acid, and distilled water(Table 2).The fat phase of mayonnaise consisted of refinedsunflower oil (Sloboda, Russia), cold-pressed pumpkinseed oil (Organic brand), and refined rice oil (Tayra,Thailand). Vinegar, sea salt, and mustard were boughtat a local shop. Egg yolk was purchased from a privatesupplier and prepared both fresh and pasteurized. Fourtypes of honey (acacia, spring, linden, and forest) werepurchased from a private supplier (Moscow region).The milk component consisted of whole milk powder(26.3% proteins, 39.8% sugars, 26% fats), skimmed milkpowder (1.5% fat) (Tagris), and whey powder (2% milkfat, 12–14% proteins, 74% lactose) (Vita-Max). Thecarbohydrates glucose, sucrose, fructose, lactose, tartaricacid, and inulin HD were purchased from Novaprodukt.Tartaric acid was added as an acidity regulator. Thefruit component (banana puree) was prepared by peelingbananas, cutting them into pieces, and crushing by stirringto obtain a homogenized sample.Mayonnaise preparation. Mayonnaise samples(300 g) with pumpkin and rice oils were prepared in thetraditional way on a T25 Ultra Turrax IKA laboratoryhomogenizer, using a S25 D-14 G-KS rotor-stator systemwith a rotor speed of 3500–24 000 rpm. For this, wepre-weighed the ingredients (fresh egg yolk, vinegar,water, and others) and mixed them with half of sunfloweroil. Then, we turned on the homogenizer and slowlyadded the rest of sunflower oil, as well as pumpkinseed and rice oils. The mixture was homogenized for3 min at 10 000 rpm at room temperature, followed byrheological analysis. Other samples were prepared in thesame way, with varying ingredients and homogenizationparameters depending on the formulation.Rheological properties. The rheological analysisof freshly prepared mayonnaise samples with pumpkinand rice oils was performed on a Brookfield rotationalviscometer with coaxial cylinders. The viscometer wasconnected to a computer equipped with Rheocalc 3.2software for measurements and data processing. Themeasurements were taken at 25 and 10°C. The temperatureswere maintained using a TC-501P Brookfieldthermostat. In particular, we determined the dependenceof shear stress (τ) and effective viscosity (μ) on shearrate (D) in the ranges of 2.15–136.6 1/s (increasingmeasurement) and 136.6–2.15 1/s (reverse measurement).We also studied the phenomenon of thixotropy, i.e. theability to restore viscous and plastic properties afterthe load is removed and deformation ceases.The experimental data showed the rheologicalmodel of mayonnaise. Particularly, the samples hadnon-Newtonian properties and belonged to pseudoplasticfluids. The rheological parameters of consistencycoefficient (k) and flow index (n) were calculated usingthe linear regression method in Microsoft Excel.Formula (1) describes the Ostwald-Reiner powerlaw used to calculate the rheological parameters.τ = k·Dn (1)where τ is the shear stress, Pa; D is the shear rate, 1/s;k is the consistency coefficient, Pa·sn; n is the flow index.Formula (2) was used to calculate effective viscosityof the mayonnaise sample:μ = k·Dn-1 (2)where μ is the effective viscosity, Pa·s.Statistical analysis. All the experiments were carriedout in triplicate. One-way analysis of variance (ANOVA)Table 1. Formulation of mayonnaise with pumpkinand rice oilsТаблица 1. Рецептура для приготовления майонезас добавлением тыквенного и рисового маселFormulation SampleContent, % Weight, gRefined sunflower oil 50.0 150.0Cold-pressed pumpkin seed oil 12.5 37.5Refined rice oil 12.5 37.5Egg products 6.2 18.6Dairy products 2.1 6.3Carbohydrates 2.2 6.6Acetic acid 3.0 9.0Sea salt 0.9 2.7Mustard 0.2 0.6Tartaric acid 0.1 0.3Distilled water 7.8 23.4Banana puree 2.5 7.5TOTAL 100 300Table 2. Formulation of mayonnaise with honeyТаблица 2. Рецептура приготовления майонеза с добавлениеммедаFormulation SampleContent, % Weight, gRefined sunflower oil 75.0 225.0Fresh egg yolk 7.7 23.1Honey 3.8 11.4Acetic acid 4.0 12.0Sea salt 0.9 2.7Tartaric acid 0.1 0.3Distilled water 8.5 25.5TOTAL 100 300743Бредихин С. А. [и др.] Техника и технология пищевых производств. 2022. Т. 52. № 4. С. 739–749was used to establish the significance of differences inthe experimental data. Data management and analysiswas performed using SPSS software and presented asmean ± standard deviation.Results and discussionRheological properties of mayonnaise with honey.We determined the influence of honey varietiesand homogenization parameters on the rheologicalproperties of mayonnaise measured at 25°C (Figs. 1and 2, Tables 3–6). Figure 1 shows the relationship betweenshear stress and shear rate for spring honey.According to the results, honey belongs to Newtonianfluids, since the line passed through the origin of thecoordinate system (Fig. 1). Table 3 presents the rheologicalproperties of the studied honey varieties expressedin terms of rheological parameters.As can be seen in Table 3, forest honey had thehighest viscosity and consistency coefficient, whilelinden honey had the lowest viscosity.The relationship between shear stress and shearrate for mayonnaise with acacia honey indicated thatthe samples with honey exhibited non-Newtonian,pseudoplastic properties (Fig. 2).Li et al. confirmed that mayonnaise is a non-Newtonianfluid that exhibits yield strength, pseudoplasticity,and thixotropy [32]. Sakai et al. reported thepseudoplastic behavior of mayonnaise with characteristicsdepending on the raw material [10].Empirical flow curves with a high degree of adequacyare described by the Herschel-Bulkley model.Table 4 shows the effect of honey on the rheologicalparameters of mayonnaise homogenized at 10 000 rpmfor 2 min at 25°C.The control mayonnaise with acacia honey had aneffective viscosity of 3.118 ± 0.001 Pa·s, a shear rate of77.82 1/s, a consistency coefficient of 77.420 ± 0.125 Pa·sn,and a flow index of 0.2624 ± 0.0003 measured at25°C. The sample with linden honey had slightly highereffective viscosity (3.294 ± 0.002 Pa·sn) and consistencycoefficient (78.460 ± 0.002 Pa·sn) compared tothe acacia honey mayonnaise. Forest honey showedhigher viscosity (3.4270 ± 0.0005 Pa·sn) and consistency(101.260 ± 0.002 Pa·sn) but a lower flow index(0.2224 ± 0.0002) compared to the other samples.Tables 5 and 6 show the effects of homogenizationtime and rotor speed on the rheological properties ofmayonnaise with acacia honey measured at 25°C.As can be seen in Table 5, the homogenization time of2 min led to an effective viscosity of 6.253 ± 0.001 Pa·sat a shear rate of 30.36 1/s, a consistency coefficient of77.42 ± 0.04 Pa·sn, and a flow index of 0.2628 ± 0.0002.Increasing the time to 4 min contributed to higherviscosity (8.7360 ± 0.0005 Pa·s) and consistency(134.240 ± 0.125 Pa·sn) but a lower flow index(0.1995 ± 0.0002).Table 6 shows the effect of the rotor speed (10 000and 12 000 rpm) during 2 min of homogenization onTable 3. Rheological properties of honeys measuredat 25°CТаблица 3. Реологические свойства различных сортов меда,измеренные при 25 °CHoney variety μ*, Pa·s k, Pa·sn nSpring honey 4.9446 6.4789 0.8950Forest honey 16.6509 17.3020 0.9851Linden honey 4.7719 7.3144 0.8341Acacia honey 5.8413 6.0930 0.9837*Effective viscosity at shear rate of 77.82 1/s.*Эффективная вязкость при скорости сдвига 77,82 1/с.Figure 1. Relationship between shear stress and shear ratefor spring honey at 25°CРисунок 1. Зависимость между напряжением сдвига искоростью сдвига весеннего меда при 25 °C0501001502002505 10 15 20 25 30 35 40 45Shear stress, PaShear rate, 1/sFigure 2. Relationship between shear stress and shear ratefor mayonnaise with acacia honey (10 000 rpm, 2 min)at 25°CРисунок 2. Зависимость напряжения сдвига и скорости сдвигамайонеза с акациевым медом (10 000 об/мин, 2 мин) при 25 °C1001201401601802002202402602805 20 35 50 65 80 95Shear stress, PaShear rate, 1/s744Bredikhin S.A. et al. Food Processing: Techniques and Technology. 2022;52(4):739–749the rheological parameters of mayonnaise with acaciahoney measured at 25°C.As can be seen, the rotor speed changed the rheologicalproperties of mayonnaise. In particular, thespeed of 10 000 rpm resulted in the effective viscosityof 6.253 ± 0.001 Pa·s at a shear rate of 30.36 1/s,a consistency coefficient of 77.42 ± 0.04 Pa·sn, and aflow index of 0.2628 ± 0.0002. Increasing the rotorspeed to 12000 rpm produced a more stable emulsionwith higher effective viscosity (8.039 ± 0.029 Pa·s)and consistency (102.320 ± 0.125 Pa·sn). The emulsion’shigher stability was due to finer fat droplets formedat the rotor speed of 12,000 rpm, which were finelydispersed in the water phase. Thus, this speed wasmore optimal than 10 000 rpm.Rheological properties of mayonnaise withpumpkin and rice oils. Figure 3 and in Tables 7–11show the effects of ingredients on the rheologicalproperties of mayonnaise with pumpkin and rice oilsmeasured at 25 and 10°C.Figure 3 features the relationship between shearstress and shear rate measured at 25°C.We found that the tested samples exhibited non-Newtonian, pseudoplastic properties, as well as thixotropy.The empirical flow curves are described by the Herschel-Bulkley model with a high degree of adequacy.Table 7 shows the effect of milk components on therheological parameters of mayonnaise homogenizedfor 3 min at 10 000 rpm.Table 5. Effect of homogenization time on the rheological properties of mayonnaise with acacia honeyТаблица 5. Влияние продолжительности гомогенизации на реологиче ские свойства майонеза с акациевым медомSample, min μ*, Pa·s k, Pa·sn n R22 6.253 ± 0.001 77.42 ± 0.04 0.2628 ± 0.0002 0,9944 8.7350 ± 0.0005 134.240 ± 0.125 0.1995 ± 0.0002 0,964*Effective viscosity at shear rate of 30.36 1/с. R2 is the coefficient of determination.*Эффективная вязкость при скорости сдвига 30,36 1/с. R2 – коэффициент детерминации.Table 4. Effect of honey variety on the rheological parameters of mayonnaiseТаблица 4. Влияние сорта меда на реологические параметры майоне заHoney variety μ*, Pa·s k, Pa·sn n R2Spring honey 3.083 ± 0.001 63.110 ± 0.029 0.3067 ± 0.0040 0.968Forest honey 3.4270 ± 0.0005 101.260 ± 0.002 0.2224 ± 0.0002 0.990Linden honey 3.294 ± 0.002 78.460 ± 0.002 0.2719 ± 0.0002 0.989Acacia honey 3.118 ± 0.002 77.420 ± 0.125 0.2624 ± 0.0003 0.994*Effective viscosity at shear rate of 77.82 1/s. R2 is the coefficient of determination.*Эффективная вязкость при скорости сдвига 77,82 1/с. R2 – коэффициент детерминации.Table 6. Effect of the rotor speed on the rheological properties of mayonnaise with acacia honeyТаблица 6. Влияние частоты вращения ротора на реологические сво йства майонеза с акациевым медомSample, rpm μ*, Pa·s k , Pa·sn n R210 000 6.253 ± 0.010 77.42 ± 0.04 0.2628 ± 0.0002 0.99412 000 8.039 ± 0.029 102.320 ± 0.125 0.2547 ± 0.0002 0.982*Effective viscosity at shear rate of 30.36 1/s. R2 is the coefficient of determination.*Эффективная вязкость при скорости сдвига 30,36 1/с. R2 – коэффициент детерминации.Figure 3. Flow curves for mayonnaise with pumpkinand rice oils at 25°CРисунок 3. Кривые течения майонеза с добавлениемтыквенного и рисового масел при 25 °C01020304050600501001502002503003504004505000,1 10 20 30 40 50 60 70Effective viscosity, Pa·sShear stress, PaShear rate, 1/sShear stressEffective viscosity01020304050600501001502002503003504004505000,1 10 20 30 40 50 60 70Effective viscosity, Pa·sShear stress, PaShear rate, 1/sShear stressEffective viscosity745Бредихин С. А. [и др.] Техника и технология пищевых производств. 2022. Т. 52. № 4. С. 739–749Table 7. Effect of milk component on the rheological properties of mayonnaise with pumpkin and rice oilsТаблица 7. Влияние молочного компонента на реологические свойст ва майонеза c добавлением тыквенного и рисового маселSample μ*, Pa·s k, Pa·sn n R2 μ*, Pa·s k, Pa·sn n R225 °C 10 °CSkimmedmilkpowder2.2290 ± 0.0002 46.870 ± 0.078 0.3005 ± 0.0030 0.998 2.7120 ± 0.0002 54.840 ± 0.029 0.3095 ± 0.0030 0.998Wholemilkpowder2.3430 ± 0.0002 55.210 ± 0.004 0.2744 ± 0.0030 0.997 2.9990 ± 0.0002 67.110 ± 0.002 0.2863 ± 0.0030 0.987Wheypowder2.3910 ± 0.0002 57.180 ± 0.003 0.2710 ± 0.0020 0.990 3.0550 ± 0.0002 69.090 ± 0.002 0.2838 ± 0.0020 0.995*Effective viscosity at shear rate of 77.82 1/s. R2 is the coefficient of determination.*Эффективная вязкость при скорости сдвига 77,82 1/с. R2 – коэффициент детерминации.Table 8. Effect of carbohydrate composition on the rheological properties of mayonnaise with pumpkin and rice oilsТаблица 8. Влияние углеводного состава на реологические свойств а майонеза с добавлением тыквенного и рисового маселSample μ*, Pa·s k, Pa·sn n R2 μ*, Pa·s k, Pa·sn n R225 °C 10 °CGlucose 2.392 ± 0.004 57.160 ± 0.078 0.2712 ± 0.0010 0.990 3.052 ± 0.004 69.060 ± 0.029 0.2837 ± 0.0010 0.995Fructose 1.997 ± 0.003 39.050 ± 0.003 0.3172 ± 0.0020 0.997 2.464 ± 0.003 55.620 ± 0.002 0.2842 ± 0.0020 0.989Sucrose 2.425 ± 0.002 58.630 ± 0.004 0.2685 ± 0.0030 0.992 3.024 ± 0.002 70.150 ± 0.002 0.2780 ± 0.0030 0.995Lactose 2.748 ± 0.001 68.480 ± 0.002 0.2615 ± 0.0020 0.993 3.031 ± 0.001 77.510 ± 0.001 0.2556 ± 0.0020 0.984InulinHD2.801 ± 0.001 69.360 ± 0.002 0.2630 ± 0.0020 0.992 3.051 ± 0.001 78.920 ± 0.004 0.2530 ± 0.0020 0.983*Effective viscosity at shear rate of 77.82 1/s. R2 is the coefficient of determination.*Эффективная вязкость при скорости сдвига 77,82 1/с. R2 – коэффициент детерминации.Table 9. Effect of egg products on the rheological properties of mayonnaiseТаблица 9. Влияние яичных продуктов на реологические свойства м айонезаSample μ*, Pa·s k, Pa·sn n R2 μ*, Pa·s k, Pa·sn n R225 °C 10 °CFreshegg yolk2.656 ± 0.002 65.640 ± 0.004 0.2634 ± 0.0020 0.991 3.144 ± 0.001 73.520 ± 0.004 0.2761 ± 0.0020 0.998Pasteurizedegg yolk2.391 ± 0.002 57.150 ± 0.003 0.2711 ± 0.0002 0.990 3.054 ± 0.002 69.090 ± 0.003 0.2838 ± 0.0030 0.995Wholeegg powder2.504 ± 0.001 54.230 ± 0.002 0.2937 ± 0.0030 0.999 3.116 ± 0.002 71.240 ± 0.002 0.2813 ± 0.0020 0.997*Effective viscosity at shear rate of 77.82 1/s. R2 is the coefficient of determination.*Эффективная вязкость при скорости сдвига 77,82 1/с. R2 – коэффициент детерминации.Table 10. Effect of homogenization time on the rheological properties of mayonnaise with pumpkin and rice oilsТаблица 10. Влияние продолжительности гомогенизации на реологич еские свойства майонеза с добавлением тыквенногои рисового маселSample,minμ*, Pa·s k, Pa·sn n R2 μ*, Pa·s k, Pa·sn n R225 °C 10 °C1 1.548 ± 0.002 42.150 ± 0.004 0.2887 ± 0.0020 0.991 2.244 ± 0.001 60.410 ± 0.004 0.2908 ± 0.0020 0.9983 1.939 ± 0.002 57.150 ± 0.003 0.2711 ± 0.0020 0.990 2.485 ± 0.002 69.099 ± 0.003 0.2838 ± 0.0030 0.9955 1.758 ± 0.001 53.610 ± 0.002 0.3282 ± 0.0030 0.999 2.208 ± 0.002 58.760 ± 0.002 0.3026 ± 0.0020 0.997*Effective viscosity at shear rate of 103.8 1/s. R2 is the coefficient of determination.*Эффективная вязкость при скорости сдвига 103,8 1/с. R2 – коэффициент детерминации.746Bredikhin S.A. et al. Food Processing: Techniques and Technology. 2022;52(4):739–749The control mayonnaise made from whey powderhad an effective viscosity of 2.3910 ± 0.0002 Pa·s, aconsistency index of 57.180 ± 0.003 Pa·sn, and a flowindex of 0.271 ± 0.002 measured at 25°C. Using skimmedmilk powder led to lower effective viscosity(2.2290 ± 0.0002 Pa·sn) and consistency (46.870 ±0.078 Pa·sn) but a higher flow index (0.3005 ± 0.0030),compared to the samples with whole milk and wheypowders. Thus, whey powder contributed to higher consistencyand viscosity of mayonnaise with pumpkinand rice oils measured at 25°C. When measured at 10°C,the rheological parameters showed higher values thanthose obtained at 25°C, which confirmed the effectof temperature on the rheological properties.Table 8 shows the effect of carbohydrate type onthe rheological parameters of mayonnaise homogenizedfor 3 min at 10 000 rpm. The measurements were takenat 25 and 10°C.The control mayonnaise was prepared with glucose.We found that the use of glucose and fructosemonosaccharides lowered effective viscosity andconsistency, compared to the use of sucrose andlactose disaccharides, inulin HD, or acacia honey.Fructose contributed to the lowest values of these parameters,while inulin HD provided the highest consistency(69.360 ± 0.002 Pa·s) and effective viscosity(2.801 ± 0.001 Pa·s), but the lowest flow index (0.2630 ±0.0020) measured at 25°C. Alvarez-Sabatel et al. foundthat the content of vegetable oil and inulin affectedthe stability and rheological properties of mayonnaisehomogenized in the rotor-stator system, as wellas under high pressure [17]. The same effects wereobserved on the rheological parameters of the sampleswith pumpkin and rice oils at 10°C.Table 9 shows the effects of egg products on therheological parameters of mayonnaise with pumpkinand rice oils homogenized for 3 min at 10 000 rpm. Themeasurements were taken at 25 and 10°C.The mayonnaise prepared with fresh egg yolk hadhigher viscosity (2.656 ± 0.002 Pa·s) and consistency(65.640 ± 0.004 Pa·sn) but a lower flow index (0.2634 ±0.0020). Using whole egg powder resulted in highereffective viscosity and consistency compared to pasteurizedegg yolk and lower values of these parameterscompared to fresh egg yolk. Higher values were obtainedfor the rheological properties at 10°C, compared tomeasurements at 25°C.Tables 10 and 11 show the effects of homogenizationtime and rotor speed on the rheological properties ofmayonnaise with pumpkin and rice oils. According tothe flow index, the mayonnaise under study belongedto non-Newtonian fluids of the pseudoplastic type.Table 10 shows the effect of homogenization time(1, 3 and 5 min) at 10 000 rpm on the rheologicalproperties of mayonnaise measured at 25 and 10°C.As can be seen, the sample homogenized for 1 minhad an effective viscosity of 1.548 ± 0.002 Pa·s at a shearrate of 103.8 1/s, a consistency coefficient of 42.150 ±0.004 Pa·sn, and a flow index of 0.2887 ± 0.0020. Increasinghomogenization time to 3 min resulted inhigher viscosity (1.936 ± 0.002 Pa·s) and consistency(57.150 ± 0.003 Pa·sn) but a lower flow index (0.2711 ±0.0020). A further increase to 5 min destroyed the structureof mayonnaise and led to lower viscosity (1.758 ±0.001 Pa·s) and consistency (53.610 ± 0.002 Pa·sn)but a higher flow index (0.3282 ± 0.0030). Measurementsat 10°C showed the same results, but higher valuescompared to those for the rheological parametersobtained at 25°C.Table 11 shows the effects of the rotor speed (10 000,12 000, and 15 000 rpm) on the rheological parametersof mayonnaise homogenized for 3 minutes. Measurementswere taken at 25 and 10°C.As can be seen, the rotor speed affected therheological parameters of the samples. An increasefrom 10 000 to 12 000 rpm led to higher effectiveviscosity (2.281 ± 0.002 Pa·s) and consistency(59.880 ± 0.003 Pa·s), as well as a lower flow index(0.2242 ± 0.0020). This meant better stability since thesystem formed a large number of small fat droplets finelydispersed in the water phase of the emulsion. A furtherincrease to 15 000 rpm resulted in an emulsion with lowereffective viscosity (1.810 ± 0.001 Pa·s) and consistencyTable 11. Effect of the rotor speed on the rheological properties of mayonnaise with pumpkin and rice oilsТаблица 11. Влияние частоты вращения ротора на реологические св ойства майонеза с добавлением тыквенного и рисового маселSample,rpmμ*, Pa·s k, Pa·sn n R2 μ*, Pa·s k, Pa·sn n R225 °C 10 °C10 000 1.939 ± 0.002 57.150 ± 0.004 0.2711 ± 0.0020 0.990 2.485 ± 0.001 69.090 ± 0.004 0.2838 ± 0.0020 0.99512 000 2.281 ± 0.002 59.880 ± 0.003 0.2242 ± 0.0020 0.999 2.515 ± 0.002 75.130 ± 0.003 0.3075 ± 0.0030 0.99615 000 1.810 ± 0.001 38.910 ± 0.002 0.3375 ± 0.0030 0.996 2.208 ± 0.002 49.560 ± 0.002 0.3299 ± 0.0020 0.995*Effective viscosity at shear rate of 77.82 1/s. R2 is the coefficient of determination.*Эффективная вязкость при скорости сдвига 77,82 1/с. R2 – коэффициент детерминации.747Бредихин С. А. [и др.] Техника и технология пищевых производств. 2022. Т. 52. № 4. С. 739–749(38.910 ± 0.002 Pa·sn), compared to the rotor speedsof 10 000 and 12 000 rpm. Thus, such a high speeddestroyed the structure of the water-fat emulsion, resultingin the system’s dilution. This phenomenon canbe observed when measuring the rheological propertiesat 10°C.ConclusionThe tested samples of mayonnaise prepared withpumpkin and rice oils, as well as various honeys, belongto non-Newtonian systems and pseudoplastic fluids.Using whey powder resulted in the highest effectiveviscosity and consistency, as well as the lowest flowindex. We also studied the effects of carbohydrates onthe rheological properties of mayonnaise with pumpkinand rice oils. Mayonnaise prepared with inulin HD hadhigher effective viscosity (2.801 ± 0.001 Pa·s) and consistency,as well as a lower flow index (0.2630 ± 0.0020),compared to the other sugars tested. Disaccharidescontributed to higher viscosity and consistency comparedto monosaccharides. Mayonnaise prepared withfresh egg yolk had higher viscosity (2.656 ± 0.002 Pa·s)and consistency (65.640 ± 0.004 Pa·sn). Forest honeyprovided mayonnaise with higher effective viscosity andconsistency, as well as a lower flow index, comparedto spring, linden, and acacia honeys. The sample withspring honey had the lowest effective viscosity andconsistency, as well as the highest flow index.The rotor speed and homogenization time also affectedthe rheological properties of mayonnaise. The samplehomogenized at 12 000 rpm had higher viscosity andconsistency, as well as a lower flow index, comparedto the sample prepared at 10 000 rpm. The same parameterswere obtained for the samples homogenizedfor 3 min. The empirical flow curves can be adequatelydescribed by the Herschel-Bulkley model.Our results may be useful for formulators of ediblefatty products, especially mayonnaise. The rheologicalproperties are important for mayonnaise consistencyand quality control during production, storage, andtransportation.ContributionS.A. Bredikhin supervised the research. All theauthors performed the experiments, processed the data,and wrote the manuscript.Conflict of interestThe authors declare that there is no conflict of interestregarding the publication of this article.