Design and Characterization of Cosmetic Creams Based on Natural Oils from the Rosaceae Family

Abstract

Background: Creams are one of the most used cosmetic formulations due to their hydrating and restoring properties, pleasant texture, and the possibility to deliver hydrophobic and hydrophilic active ingredients. The study aims to develop and characterize cosmetic creams based on natural-sourced ingredients—different vegetable oils from the Rosacea family: (1) Chaenomelis japonica seed oil, (2) Rosa canina seed oil, (3) Prunus armeniaca kernel oil, alone and in combination (4), along with silk protein (sericin) and astaxanthin. Methods: The creams were prepared by the hot homogenization method and were characterized in terms of rheological properties, spreadability, and antioxidant activity. Results: Two suitable formulations were selected as feasible for cosmetic application—the model containing Chaenomelis japonica seed oil exhibiting the highest antioxidant activity (47% higher vs. the model based on rosehip oil by FRAP method) and the highest spreadability values among the tested formulations (ranging between 61.57 and 69.34 mm). The second selected optimal formulation is the model based on a combination of oils characterized by the most suitable consistency and high antioxidant activity. Conclusions: The differences in their rheological behavior suggest as feasible application of Japanese quince oil cream its use as a daycare antioxidant cream, whereas the mixed oils-based cream model may potentially serve as a night cream for restorative and antioxidant care.

1. Introduction

Creams are semi-solid forms for application to the skin, characterized by a thick-viscous consistency, directly dependent on the quantitative ratio between the main components of which they are composed—oil and water phase. They have a variety of cosmetic functions, including cleansing, improving appearance, protecting, and moisturizing. Depending on their composition and the quantitative ratio of the phases, hydrophilic and hydrophobic creams can be distinguished [1]. One of the current trends in cosmetic product development is the use of natural ingredients, which have attracted consumers’ interest due to their effectiveness, good tolerability profile, and the added value of environmental responsibility. In this regard, the composition of the elaborated creams is primarily based on natural-sourced ingredients such as vegetable oils, silk protein, and astaxanthin. Natural plant oils and bioactive sea-derived constituents have attracted enormous interest in cosmetics due to their antioxidant, skin-rejuvenating, and barrier-supporting properties. The selected oils from the Rosaceae family (rosehip, apricot kernel, and Japanese quince oils) are rich in unsaturated fatty acids and tocopherols that contribute to skin nourishment and oxidative protection. Although there are studies focused on the elaboration of cosmetic creams based on rosehip [2] and apricot kernel oil [3], there is no data in the literature about creams based on Japanese quince oil, as well as on the combination of the three oils, which addresses a research gap worth investigating. The comparative analysis of the three oils, formulated in the same cream base, separately and blended, would indicate lipid composition-dependent effects on the spreadability, rheological, and antioxidant properties of the elaborated creams, thereby enriching the research progress in this area. Additionally, the novelty of our work lies in the inclusion of sericin and astaxanthin in the formulations, which, despite being individually studied, their combined use with each other as well as with natural oils hasn’t been explored yet. The evaluated rheological and mechanical properties, along with the antioxidant activity of the developed creams, will enable a correlation between their sensory/performance characteristics and functional efficacy, providing a practical guideline for the development of antioxidant cosmetic creams.

The seeds of Chaenomeles japonica (Japanese quince) are the primary source to derive oils rich in polyunsaturated fatty acids (PUFAs) and lipophilic bioactive compounds such as tocopherols, phytosterols, and carotenoids [4]. Nineteen fatty acids were identified in Japanese quince oil, with the highest content found for linoleic acid (52.4%), oleic acid (33.8%), and palmitic acid (9.5%), which represent 95.7% of the total fatty acids. The fatty acids in Japanese quince oil can be incorporated into cell membranes and regenerate the damaged lipid barrier of the epidermis, limiting transepidermal water loss (TEWL). When applied to the skin, they can maintain a pH between 4.0 and 6.5, creating a protective barrier [5]. Japanese quince oil also contains phytosterols (β-sitosterol), tocopherols, β-carotene, and squalene. Beta-carotene exhibits powerful antioxidant potential, effectively neutralizing the singlet form of oxygen. It penetrates well into the stratum corneum and accumulates to some extent in the cell membranes of corneocytes. In the epidermal layers, β-carotene is transformed into retinol and its esters [6]. The rich composition of Japanese quince oil determines its beneficial effects upon cosmetic application, such as antioxidant protection, skin barrier maintenance and hydration, which contribute towards a vital and radiant appearance.

Apricot oil is derived from the kernels of Prunus armeniaca and is highly valued for its beneficial effects on skin, hair, and health [7]. The cold-pressed technique is one of the most commonly used methods for extraction, resulting in a final product rich in fatty acids (92–98%), phytosterols (α-sitosterol), and tocopherols [8]. Among the PUFAs, the most abundant are oleic acid (between 69.79% and 74.3%) and linoleic acid (22.10–22.69%) [9], contributing to enhanced skin hydration and resilience. A characteristic of apricot kernel oil is the presence of amygdalin, a cyanogenic glycoside, ranging from 3% to 12% and is known for its anti-inflammatory and antioxidant effects. It can also alleviate psoriasis lesions and improve skin barrier damage [10]. The combination of essential fatty acids, tocopherols, phytosterols, and amygdalin upon topical application can improve skin elasticity, reduce irritation, and restore the epidermal lipid matrix, thereby providing smoother and hydrated skin.

Similar to its counterparts from the Rosaceae family, rosehip seed oil also contains PUFAs, with the most abundant linoleic acid (35–55%), α-linolenic acid (25–35%), and oleic acid (10–20%). Linoleic and α-linolenic acids are known for their beneficial skin effects, such as maintenance of the stratum corneum permeability barrier, formation and secretion of lamellar bodies, inhibition of pro-inflammatory eicosanoids, and cytokines (tumor necrosis factor-alpha, interferon-gamma, and interleukin-12) [11]. Oleic acid exhibits good penetrating properties and can contribute towards the reduction of fine lines and wrinkles [12]. In addition to the fatty acids, rosehip oil also contains tocopherols, phytosterols, and phenolic acid. Among the latter of particular interest are ferulic acid, due to its ultraviolet (UV) absorption and collagen-stimulating abilities, as well as caffeic and cinnamic acids [13]. The complementary presence of all these constituents accounts for rosehip oil’s recognized cosmetic performance—enhancing skin renewal, elasticity, and radiance, while simultaneously providing effective protection against oxidative stress and photoaging.

The elaborated cosmetic creams are further enriched with sericin and astaxanthin. Sericin constitutes 25–30% of the silk protein produced by silkworms. It is known to stimulate collagen synthesis, restore the amino acids in epidermal cells, reduce TEWL, and inhibit the activity of tyrosine, which affects melanin formation and promotes skin whitening [14,15,16]. Astaxanthin is a carotenoid obtained from the green algae Haematococcus pluvialis. Its beneficial effects on the skin are expressed in the suppression of hyperpigmentation, melanin synthesis, inhibition of photoaging, and reduction of wrinkle formation [17]. Astaxanthin improves the deoxyribonucleic acid (DNA) repair capacity of cells exposed to UV radiation. It can minimize DNA damage as well as influence the kinetics of its repair [18].

The current study aimed to develop and characterize cosmetic creams containing different natural oils from the Rosacea family—Chaenomelis japonica seed oil, Rosa canina seed oil, Prunus armeniaca kernel oil, along with sericin and astaxanthin. The elaborated creams were characterized in terms of rheological properties, spreadability values, and antioxidant activity.

2. Materials and Methods

2.1. Materials

Cold-pressed rosehip seed oils (Rosa canina seed oil) and apricot kernel oils (Prunus Armeniaca (Apricot kernel oil), emulsifying base for the preparation of cosmetic creams Neofin Nat (cetearyl alcohol, polyglyceryl-3 stearate, caprylic/capric triglycerides, sodium stearoyl lactylate, hydrogenated coconut oil, shea butter, octyldodecanol, beeswax), silk protein (sericin), astaxanthin concentrate extracted from Haematococcus pluvialis algae, and preservative (phenoxyethanol) were ordered from Dobika Trend Ltd., Bulgaria (https://www.ekomama.net (accessed on 7 April 2025)). Cold-pressed Japanese quince oil (Chaenomeles japonica seed oil) was ordered from O&3 Poland sp. z.o.o (https://www.oand3.com/ (accessed on 12 April 2025)). Propylene glycol flavors of quince and apricot were ordered from P. Toshev Ltd., Bulgaria (https://www.sortovisemena.bg (accessed on 20 April 2025)). 1,1-diphenyl-2-picrylhydrazyl (DPPH), 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (Trolox), and acetate buffer were obtained from Sigma-Aldrich Chemie GmbH, Darmstadt, Germany. Methanol, 2,4,6-tripyridyl-s-triazine (TPTZ), hydrochloric acid, and ferric chloride hexahydrate were purchased from Merck KGaA, Darmstadt, Germany.

2.2. Methods

2.2.1. Preparation of Cosmetic Creams

The cosmetic creams were prepared by the hot emulsification method. In the preliminary experimental work, the technological parameters were varied as follows: homogenization speed—8000, 9000, and 10,000 rpm (revolutions per minute); homogenization time—3, 5, or 7 min; temperature—60 °C and 80 °C.

To derive optimal process conditions, a cream based on the emulsifying base Neofin Nat (8% w/w) and quince oil (8% w/w) was prepared by varying the above-listed parameters. The conditions under which the highest emulsion stability was achieved after centrifugation were selected for the preparation of the four models of cosmetic creams, containing the emulsifying base Neofin Nat (8% w/w). An oil phase (8% w/w) was added to the composition, with the oil content varying as follows: quince oil 8% (w/w) (C1); rosehip oil 8% (w/w) (C2); apricot oil 8% (w/w) (C3), quince oil 2.7% w/w), rosehip oil 2.7% (w/w) and apricot oil 2.7% (w/w) (C4). An accurately weighed amount of the emulsifying base and the oil phase was heated in a water bath (80 °C) in a beaker until a melt was obtained. The necessary amount of purified water was heated to the same temperature; afterwards, both phases were mixed and homogenized using an ULTRA-TURRAX T25 digital homogenizer (IKA-Werke, Staufen, Germany) at 9000 rpm for 5 min. After cooling down the mixture to a temperature of 38 °C, the preservative phenoxyethanol (0.1%) (w/w), astaxanthin (0.005% w/w), and silk protein (0.1% w/w) were added to the mixture. The mixture was again homogenized for 2 min at 9000 rpm until the characteristic semi-solid consistency was obtained. Four drops of quince essence were added to composition (C1), four drops of apricot essence to composition (C3), and to composition (C4)—a mixture of two drops of quince essence and two drops of apricot essence.

2.2.2. Characterization of Cosmetic Creams

The organoleptic characteristics of the prepared creams were evaluated in terms of the following parameters: physical state, color, aroma, texture, and consistency [19].

The pH of the creams was determined potentiometrically using a portable digital pH meter (pH 70 Vio, XS Instruments, Carpi, Italy). A total of 5 g of sample was added to 20 mL of distilled water, preheated to 37 ± 2 °C, and stirred vigorously for 1 min. After cooling, the dispersion was filtered, and the pH of the filtrate was measured. The experiment was performed in triplicate [20].

The type of emulsion was determined by a dilution test. A small amount of each cream (5.0 g) was divided into two parts; one part was diluted with water (10 mL) and the other with sunflower oil (10 mL). An o/w (oil-in-water) emulsion will mix thoroughly with water but will not dissolve into an oily substance. In contrast, a w/o (water-in-oil) emulsion will separate when mixed with water and will mix by dilution with the oil phase. The test was repeated for each cream separately.

The formation of emulsions was also confirmed by microscopic evaluation. A sample of 1.0 g was dissolved in purified water and homogenized to obtain a homogenous emulsion. Afterwards 10 µL of sample was placed on a microscope slide and evaluated at 40× magnification using an optical microscope (Leica DM1000, Leica Microsystems, Wetzlar, Germany), equipped with a Leica MC170HC camera.

Descriptive statistics were performed by measuring the diameter of 60 droplets. The standard error, mean droplet diameter, and the upper and lower limits of the confidence interval were calculated for this purpose.

2.2.3. Emulsion Stability

To test the stability of the cosmetic creams, 0.5 g of each type were placed in test tubes and centrifuged at a speed of 10,000 rpm for 10 min using microcentrifuge (D2012 Plus, DLAB Scientific, Rowland St. City of Industry, CA, USA; rotor capacity 12 tubes of 2.0 mL; r = 7.9 cm, max. speed 15,000 rpm) for three consecutive cycles [21]. In this method, the centrifugal force is significantly larger than the gravitational force and will accelerate the creaming of the emulsions. Any signs of precipitation or phase separation indicate insufficient emulsion stability [22].

The emulsion stability was also evaluated using a freeze–thaw test, conducted according to the methodology described by Wang et al. [23]. The tested formulations were placed in a Petri dish (diameter = 70 mm; height = 12 mm) in an amount that exhibited a thickness of 10 mm. The samples underwent three cycles of freezing (24 h at 18 °C each) and thawing (4 h at 25 °C each), and were evaluated with respect to phase separation, crystallization or sedimentation, changes in color, fragrance and viscosity. The experiment was performed in triplicate (n = 3).

2.2.4. Spreadability

The spreadability of creams was determined by the parallel plate method using two glass plates with a diameter of 9 cm at 25 ± 2 °C. A 1.0 g sample of the cream was placed between the plates and pressed with a 50 g weight. After 1 min, the weight was removed, and the spreadability diameter (expressed in centimeters) was measured. Each measurement was performed in triplicate [24].

2.2.5. Rheological Studies

Rheological measurements were performed using a HAAKE™ Viscotester™ 550 (Thermo Fisher Scientific, Waltham, MA, USA), at a temperature of 32 ± 1 °C. Triplicate analyses were performed in a coaxial cylindrical SV DIN sensor at shear rates ranging from 0.0123 s⁻¹ to 100 s⁻¹. The data were examined for shear stress as a function of the percentage of fraction for each model. The main rheological parameters were obtained using two nonlinear relationships—the Ostwald de Veele power model and the Herschel–Bulkley model (

Table 1. Mathematical models applied to calculate the rheological parameters of the semisolids [25].

Model	Mathematical Equation
Power law model (PLM)	$\tau =K·{\gamma }^n$
Herschel–Bulkley model (HBM)	$\tau ={\tau }_0+ K·{\gamma }^n$

Note: τ, shear stress; γ, shear rate; τ₀, yield stress; K, consistency index; n, power law index.

).

2.2.6. Antioxidant Activity

The antioxidant activity of the developed creams was evaluated by two methods. Each test sample was prepared by mixing 2.0 g of cream and 8 mL 70% ethanol. The mixture was homogenized for 5 min, on the vortex. After homogenization, the samples were centrifuged at 4500 rpm for 10 min. The supernatant was used for subsequent analyses.

• DPPH Assay

The selected technique provides information on the scavenging ability of the DPPH radical and involves the mechanisms of mixed hydrogen atom transfer (HAT) and single electron transfer. The analyzed model (0.15 mL) was mixed with 2.85 mL of freshly prepared 0.1 mM DPPH methanolic solution. The mixture was left for 15 min at elevated temperature (37 °C) without direct access to light; afterwards, the decrease in the absorbance at 517 nm was measured using Camspec M107 VIS spectrophotometer (Spectronic-Camspec Ltd., Leeds, UK). The data obtained were analyzed in a comparative aspect to a control methanolic sample, and the percentage of inhibition was determined [26]. Afterwards, a calibration curve with Trolox was created, and the obtained results are presented as micromoles of Trolox equivalent per 100 g.

• Ferric Reducing Antioxidant Power (FRAP) Assay

The method evaluates the antioxidant activity of a sample by its ability to reduce ferric ions. The sample was prepared following the protocol of Benzie & Strain [27] with slight modifications. The reagent for the assay involves mixing 100 mL of 0.3 M acetate buffer (pH 3.6), 10 mL of 10 mM TPTZ in 40 mM hydrochloric acid, and 10 mL of 20 mM ferric chloride hexahydrate in distilled water. The reaction was conducted by mixing 3.0 mL of FRAP reagent with 0.1 mL of the tested sample, under the following conditions: reaction time—10 min, temperature—37 °C in the absence of light. The absorbance was measured at λ = 593 nm using a Camspec M107 VIS spectrophotometer (Spectronic-Camspec Ltd., Leeds, UK) against a reference methanolic sample.

2.2.7. Statistical Analysis

All experiments were conducted in triplicate. For better interpretation, results are expressed as mean values ± the estimated 95% confidence intervals. Statistical comparisons among sample groups were performed using Duncan’s multiple range test, with significance set at p < 0.01. Data analyses were conducted using SPSS statistical software (Version 27 for IBM statistics; IBM Corp., Armonk, NY, USA). The obtained data were analyzed in triplicate and expressed as mean ± standard deviation (SD).

3. Results and Discussion

3.1. Preparation of Cosmetic Creams by Varying the Content of Individual Oils and Technological Parameters

In the process of developing cosmetic creams, it is essential to select an appropriate preparation method that provides excellent physical stability of the biphasic dermal form. The classical emulsification method was used as a method for preparing cosmetic creams, and two temperature regimes were studied: 60 °C and 80 °C. A current tendency in the development of cosmetic products based on natural ingredients is their homogenization at a lower temperature to preserve the stability of the biologically active compounds.

In this particular case, the cream prepared at a temperature of 60 °C showed signs of phase separation several hours after preparation (regardless of the tested speed and homogenization time), which may be attributed to the higher viscosity of the melt, hindering the homogenization process and the uniform distribution of the emulsifier film onto the oil droplets. Therefore, a temperature of 80 °C was chosen as the optimal temperature for emulsification of the biphasic formulations.

Regarding the speed and homogenization time, it has been found that higher speeds, as well as longer homogenization times, induce air bubbles and, respectively, the formation of foam in the system, which persists even after cooling the cream and compromises the desired thick-viscous consistency. In this regard, the emulsification parameters were chosen as follows: homogenization speed of 9000 rpm and homogenization time of 5 min.

Based on the information provided in the technical specifications by the manufacturer, the concentration of the formulation constituents was selected (

Table 2. Composition of cosmetic creams.

Composition (% w/w)	C1	C2	C3	C4
Neofin Nat	8%	8%	8%	8%
Chaenomelis japonica seed oil (Japanese quince seed oil)	8%	-	-	2.7%
Rosa canina seed oil (Rosehip oil)	-	8%	-	2.7%
Prunus armeniaca kernel oil (Apricot kernel oil)	-	-	8%	2.7%
Astaxanthin	0.005%	0.005%	0.005%	0.005%
Silk protein (Sericin)	0.1%	0.1%	0.1%	0.1%
Phenoxyethanol	0.1%	0.1%	0.1%	0.1%
Purified water	up to 100%	up to 100%	up to 100%	up to 100%
Fragrance	Cydonia oblonga (quince) 4 drops	-	Prunus armeniaca (apricot) 4 drops	Mixture of Cydonia oblonga (2 drops) and Prunus armeniaca (2 drops)

). The selected low concentration of sericin among the commonly used in cosmetics range (0.1% to 3%) is a prerequisite for good skin tolerability and safety profile. The concentration of astaxanthin was selected during preliminary studies based on the physical appearance, in particular, the color of the obtained creams.

The evaluation of the organoleptic parameters of the prepared creams is summarized in

Table 3. Characteristics of cosmetic creams.

Physical Appearance	C1	C2	C3	C4
Physical state	semisolid	semisolid	semisolid	semisolid
Color	orange-light beige	peach beige	pale pink-beige	pale orange-light beige
Fragrance	quince	rosehip	apricot	fruity
Texture	smooth	smooth	smooth	smooth
Consistency	thick viscous	thick viscous	thick viscous	thick viscous
pH	5.5 ± 0.07	5.34 ± 0.04	6.03 ± 0.08	6.12 ± 0.02

. The physical state of all four models meets the definition of semi-solid formulations for dermal application. The creamy, thick-viscous consistency may be related to the content of beeswax, hydrogenated coconut oil, and shea butter as thickeners, with a total oil phase below 10%. The presence of astaxanthin, a natural red-orange pigment, is responsible for the observed intense coloration in combination with the color of the corresponding oil (Figure 1). The fragrance of creams C1, C3, and C4 is fresh, sweet-fruity, and unobtrusive, and is a result of the additionally added essences of quince and apricot. Model C2 has a natural aroma of rosehip characteristic of the cold-pressed oil.

All of the elaborated creams exhibited a pH value suitable for dermal application, corresponding to the skin’s acid mantle, which is a prerequisite for good tolerability during application.

The prepared creams are emulsions of the O/W type, i.e., hydrophilic creams, which is a prerequisite for good tolerance and feeling on the skin, as well as for its uniform coverage. Hydrophilic creams are known to absorb quickly and are easily removed without forming a greasy film or leading to a comedogenic effect. The formation of the emulsion was further confirmed by microscopic analysis, as evident from Figure 2.

The presented micrographs revealed the formation of well-defined spherical droplets with smooth contours and preserved integrity dispersed in a continuous aqueous phase. Most homogenous droplet distribution was observed in the sample based on Japanese quince oil (Figure 2a), illustrating predominantly small droplets with sizes below 20 µm, which demonstrates the efficient homogenization process and effective stabilization of the dispersed phase. On the contrary, the cream based on rosehip oil (Figure 2b) showed a broader size distribution with several droplets with irregular shape, which may be related to uneven distribution of shear forces or insufficient homogenization energy. The creams based on Apricot kernel oil and the mixture of oils showed slightly higher polydispersity compared to model C1; however, the clear boundaries of the droplets are preserved, indicating efficient interfacial stabilization by the employed emulsifier. The predominant prevalence of droplets with spherical morphology, as well as the absence of aggregated domains indicates the formation of stable emulsions. The size of droplets is presented in

Table 4. Size of droplets of cosmetic creams.

	C1	C2	C3	C4
Statistic Type	Diameter (µm)	Diameter (µm)	Diameter (µm)	Diameter (µm)
Mean	8.084	7.963	7.268	11.111
Standard Error	1.025	0.665	0.755	1.113
Confidence Interval Lower	6.075	6.659	5.788	8.928
Confidence Interval Upper	10.094	9.267	8.748	13.294
Total Count	60	60	60	60

.

The mean droplet size below 15 µm and the narrow confidence intervals observed for all formulations suggest high kinetic stability and the absence of coalescence. Only the combined-oil formulation (C4) showed a slight tendency toward increased polydispersity, which might become evident during long-term storage but does not compromise the immediate stability of the system.

3.2. Emulsion Stability

From a thermodynamic point of view, emulsions, including creams, are characterized by low physical stability resulting from the combination of two immiscible liquids; therefore, assessing their emulsion stability is an integrated part of the formulation process. Physical instability of emulsions manifests itself in various processes such as flocculation, phase separation, or coalescence. The optimal concentration of emulsifiers and the appropriate preparation method are the most important factors influencing this process. The elaborated cosmetic creams are characterized by excellent physical stability, retaining their integrity after three consecutive cycles of centrifugation at 10,000 rpm for 10 min.

The stability of the formulations was also evaluated by the freeze–thaw test. After 3 consecutive cycles of freezing and thawing, no visual alterations (e.g., phase separation, crystallization/sedimentation, or changes in color) in the creams were observed, indicating good physical stability of the samples. The formulations were considered stable (i.e., no phase separation) when no visible oil/aqueous layer formation or creaming was observed after the experiments, and the creams maintained their uniform color and homogenous texture. The changes in their rheological properties after the induced thermal stress are discussed in Section 3.6.

3.3. Spreadability

The spreadability of cosmetic creams is an important characteristic, directly influencing their effectiveness, as well as consumer preferences. The selected experimental setup is often reported in relevant studies [23,28]. Although the surface temperature does not fully replicate skin conditions (~32 °C), this standardized setup enables a comparative evaluation of the tested formulations under controlled conditions, which is an important criterion at this stage of the study. High spreadability values contribute to the easy and uniform distribution of the cream on the skin, as well as to the facilitated extrusion process. The obtained results fall within the range (5–7 cm) (Figure 2), corresponding to good spreadability of the formulations [28].

As evident from Figure 3, the model containing Chaenomelis japonica seed oil exhibited the highest spreadability values, followed by the one based on Prunus armeniaca kernel oil. Conversely, the formulations containing Rosa canina seed oil in their composition (C2 and C4) were characterized by lower spreadability capacity. The results obtained can be explained by the differences (qualitative and quantitative) in the composition of the individual oil phases. The higher concentration of unsaturated fatty acids—linoleic, ranging between 36% and 55%, and linolenic acid (17–27%) in rosehip oil [29] determines its more viscous consistency, corresponding to the observed lower spreadability. Simultaneously, the lower amount of oleic acid (between 15% and 22%) compared to that found in the apricot kernel oil (between 60% and 75%) [30], as well as in the Japanese quince-derived oil (approx. 35%) [31], accounts for the observed higher spreadability values. The results obtained are in accordance with the data from the conducted rheological studies.

3.4. Rheological Studies

The flow curves of the developed creams are presented in Figure 4. It is noteworthy that the creams exhibit non-Newtonian behavior, which is characterized by an increase in shear stress (τ) values with increasing shear rate ($\stackrel{·}{ɣ}$). No threshold stress was found for this type of flow, indicating that the studied cream model will begin to flow immediately after applying shear stress. The flow index (n) is often used to evaluate the deviation of the fluid from Newtonian flow. Values of n < 1 correspond to shear-thinning (pseudoplastic) behavior, whereas values of n > 1 indicate shear-thickening (dilatant) behavior [32].

The rheological analysis of the cosmetic cream samples (C1–C4) revealed a pronounced pseudoplastic behavior (n < 1), typical of concentrated colloidal dispersions and oil-based systems [33], as evidenced by the nonlinear relationship between shear stress and shear rate (τ = f($\stackrel{·}{ɣ}$)) (Figure 4) and flow behavior index values below unity (n < 1) (

Table 5. Rheological parameters of the samples obtained from Power-law (PLM) and Herschel–Bulkley (HBM) models. Values are means ± 95% CI.

Type of Model	C1	C2	C3	C4
PLM	K = 40.015 ± 0.985 Pa·sn n = 0.143 ± 0.006 R2 = 0.858	K = 46.465 ± 0.824 Pa·sn n = 0.164 ± 0.002 R2 = 0.951	K = 46.302 ± 0.857 Pa·sn n = 0.164 ± 0.004 R2 = 0.946	K = 57.368 ± 1.521 Pa·sn n = 0.171 ± 0.006 R2 = 0.911
HBM	τ0 = 0.003 ± 0.000 Pa K = 40.199 ± 1.286 Pa·sn n = 0.143 ± 0.004 R2 = 0.856	τ0 = 0.002 ± 0.000 Pa K = 52.310 ± 1.090 Pa·sn n = 0.148 ± 0.002 R2 = 0.940	τ0 = 0.001 ± 0.000 Pa K = 52.270 ± 1.020 Pa·sn n = 0.147 ± 0.003 R2 = 0.9276	τ0 = 0.002 ± 0.000 Pa K = 57.371 ± 1.180 Pa·sn n = 0.170 ± 0.032 R2 = 0.911

). This behavior facilitates application on the skin without excessive pressure, while the high viscosity at low shear rates ensures product stability during storage and prevents undesired flow. A moderate shear stress at the onset of deformation provides a comfortable sensation upon application and favorable spreading properties [34]. Among the studied formulations, the combined-oil cream (C4) exhibited higher viscosity and shear stress values, suggesting its feasibility as a restorative and protective product [35,36]. In contrast, the Japanese quince (C1) oil-based cream showed the lowest values of these parameters, suggesting its suitability for daily use.

The flow curves (Figure 4) were modeled using both the Power-law (PLM) and Herschel–Bulkley (HBM) equations (Table 5). The PLM provided a satisfactory description of the rheological behavior (R² = 0.858–0.951), with consistency indices (K) ranging from 40.02 to 57.37 Pa·sⁿ and flow behavior indices (n) between 0.143 and 0.171. The HBM suggested negligible yield stress values (τ₀ = 0.001–0.003 Pa) and did not significantly improve the fit (R² = 0.856–0.940); therefore, the simpler Power-law model was considered sufficient to describe the flow behavior of the tested systems. The negligible yield stress values obtained from the Herschel–Bulkley model indicate that the elaborated creams behave as soft viscoelastic materials that begin to flow almost immediately upon application of shear. This suggests the absence of a strong internal gel network or structural rigidity within the formulations—a desired characteristic for topical creams ensuring smooth spreading and sensory comfort.

The relatively high K value observed for formulation C4 suggests enhanced stability [37] and the potential for further loading with active ingredients, supporting its potential suitability as restorative or night cream. Overall, the rheological profile of the formulations corresponds well to the requirements for modern cosmetic and pharmaceutical products.

The relationship between the viscosity of the studied creams as a function of the change in shear rate is depicted in Figure 5.

All creams showed a characteristic decrease in viscosity with increasing shear rate, confirming that the formulations exhibited pseudoplastic rheological behavior. The model based on a combination of oils (C4) exhibited the highest initial viscosity, indicating stronger intermolecular interactions and more efficient packing within the cream matrix, which led to enhanced stability at rest. The models based on rosehip oil (C2) and apricot oil (C3) exhibit a similar rheological profile, characterized by a slightly lower initial viscosity (~6000 mPa·s), but follow an almost identical shear decay curve, indicating good rheological stability. The model containing Japanese quince oil was characterized by the lowest initial viscosity, which corresponds to the highest spreadability values obtained. An inverse relationship between the spreadability values and viscosity was also established in a study by Djiobie Tchienou et al. [38], which developed a topical cream based on vegetable (sesame, soybean) or mineral (liquid paraffin) oils and Aloe vera.

3.5. Freeze–Thaw Test

The freeze–thaw stability test is often used to evaluate the resistance of semisolid formulations to temperature-induced structural stress, providing a predictive measure of the long-term stability of the product. The results of the performed experiment with respect to changes in the average viscosity of the samples after each cycle are presented in

Table 6. Changes in viscosity of tested samples after each cycle freeze–thaw test (n = 3). Values are means ± 95% CI.

	C1	C2	C3	C4
Cycle	η (Pa·s)	η (Pa·s)	η (Pa·s)	η (Pa·s)
1	2030.32 ± 22.57	688.61 ± 3.71	7114.67 ± 19.76	9827.00 ± 15.31
2	4918.52 ± 27.66	6482.68 ± 11.12	5436.83 ± 17.78	9300.54 ± 17.29
3	7849.30 ± 16.80	2.50 ± 0.25	6879.00 ± 18.03	9100.27 ± 16.80

.

Although no visual changes in the formulations were observed during and after the experiment, there were variations in the viscosity of the samples. The cream based on Japanese quince seed oil (C1) exhibited an increase in the viscosity after each freeze–thaw cycle, which may be attributed to structural reorganization within the matrix. During the freezing stage, partial dehydration of the aqueous phase can induce closer packing of the amphiphilic molecules and stronger hydrogen bonding upon thawing, leading to the formation of a more interconnected semi-solid network. In this regard, the repeated cycles of freezing and thawing correspond to the observed higher viscosity values after each cycle as the internal phase becomes more resistant to flow. Formulations C3 and C4 maintained high viscosity values with slight variations throughout the experiment, which demonstrated effective interfacial stabilization and strong resistance to droplet coalescence. The formulation C2, in contrast, exhibited a sharp decrease in the viscosity on day 3, which indicates insufficient physical stability and corresponds to a shorter shelf-life. The abrupt change in the viscosity of formulation C2 may be related to the interactions within the polycomponent system. A polymorphic transition of the structuring lipids from the fine β′ to the coarser, less stable β crystals may reduce the network connectivity and enable rosehip oil expulsion and disarrangement of the interfacial film [39]. Additionally, the low oleic and high PUFA content in rosehip oil may further promote phase separation and hinder recrystallization [40], leading to network destabilization and the observed viscosity loss.

3.6. Antioxidant Activity

The results from the antioxidant activity studies are presented in

Table 7. Antioxidant activity of the tested creams. Values are means ± 95% CI. *

Cream Formulation	DPPH Method (μmol TE/100 g)	FRAP Method (μmol TE/100 g)
C1	79.85 c ± 1.47	122.17 a± 5.47
C2	105.37 a ± 2.20	120.10 a ± 3.01
C3	72.57 d ± 2.32	82.87 b ± 2.56
C4	93.38 b ± 2.40	120.40 a ± 3.00

* Means in a column with a common superscript letter (a–d) differ (p < 0.05) as analyzed by Duncan test. Values with the same letter are not significantly different according to Duncan’s test (p < 0.05).

. The data showed that rosehip oil-based cream exhibited the highest value for radical scavenging activity—105.37 μmol TE/100 g, and the Japanese quince-based one—the highest metal reducing ability—122.17 μmol TE/100 g.

Due to the lack of a standard for determining the antioxidant activity of cosmetic products, various authors have defined ranges for evaluation. Higher values obtained by DPPH analysis correspond to a higher ability for neutralization of free radicals. The high values obtained by the FRAP method are an indication of strong antioxidant activity of the tested sample, due to the greater ability to reduce ferrous (Fe³⁺) ions to ferric (Fe²⁺).

A series of studies devoted to the antioxidant activity of oils and fruits/seeds of Rosa canina revealed significant variations depending on the method used and source material. The antioxidant activity showed heterogeneous values: the cold-pressed oil exhibited a DPPH activity of 7.21 mg/mL [41], whereas the essential oil extracted from fruits showed 38.50–39.49% inhibition (DPPH) and 140.12–159.33 μmol TE/g (FRAP) [42]. A possible explanation may be differences in the metabolic composition of the two oils. The cold-pressed oil contains mainly PUFAs presented by linoleic acid (50–65%), oleic acid (29–38%), and α-linolenic acid (0.2–7%) [41], which are highly susceptible to oxidation and decrease the oxidative stability of the oil. Its antioxidant activity is primarily attributed to the presence of minor components such as tocopherols and residual phenolic compounds (e.g., p-coumaric and ferulic acid methyl ester) [41], which explains the observed low DPPH activity. The volatile secondary metabolites, such as phenolic compounds (e.g., carvacrol), monoterpenes (e.g., limonene, p-cymenene), and monoterpenoids (e.g., α-terpineol, carvone) [42] present in the essential oil extracted from fruits have been documented to possess strong electron- and hydrogen-donating capability, leading to the observed results. Regarding rosehip seeds and fruits, the highest DPPH activity was found in dried and ground fruits—517.04 mg TE/100 g, which may also be attributed to the estimated high amount of phenolic compounds (1678 mg GAE/100 g). [43]. Frozen fruits of different varieties showed values in the range of 102.27–108.02 μmol TE/100 g [29]. The authors estimated a positive correlation between polyphenols and ascorbic acid contents and the antioxidant capacity of the tested samples. The results from the current study showed a comparable DPPH activity of 105.37 μmol TE/100 g compared to the results found for frozen fruits from different morphological forms of the plant—108.02 μmol TE/g; 107.30 μmol TE/100 g and 102.27 μmol TE/100 g [44]. By the FRAP method, the value also corresponds to the data from the literature—it is comparable to that of the essential oil (140.12 μmol TE/g) [42].

The antioxidant activity of the cream with Chaenomeles japonica oil was estimated as follows: DPPH analysis—79.85 μmol TE/100 g and FRAP analysis—122.17 μmol TE/100 g. The database used for comparison with other sources showed us varying values. When extracting the fruits of the Japanese quince with ethanol, values of 29.09 mg TE/g (DPPH) and 15.88 mg TE/g (FRAP) were recorded [45]. A study of freeze-dried and extracted fruits of different varieties (Darius, Rondo, and Rasa) reported the following values: Darius—115.9 μmol TE/100 g; Rondo—99.1 μmol TE/100 g; Rasa—106.5 μmol TE/100 g [46]. The obtained values for the antioxidant activity of the cream containing Chaenomeles japonica oil were significantly higher compared to most of the studied samples from the literature, including extracts and natural fruits, which may be related to the formulation constituents, e.g., the emulsifying base, facilitating solubilization, or stabilization of the antioxidant compounds.

The cream with Prunus armeniaca oil exhibited the following antioxidant activity values: DPPH analysis—72.57 μmol TE/100 g and FRAP analysis—82.87 μmol TE/100 g. Compared to the published values for apricot seed oils obtained by cold pressing or extraction with organic solvents, the cream demonstrated significantly higher antioxidant activity. According to Fratianni et al. [47], cold-pressed apricot oil showed a DPPH activity of 10.01 μg/mL and a FRAP activity of 0.128 (mg QE/gr), respectively. Additionally, Popa et al. [48] and Stryjecka et al. [30] reported FRAP values between 0.86 and 1.38 mM Fe²⁺/L (for oils extracted with petroleum ether or n-hexane), which is also significantly lower than the results found for the elaborated cream. The observed higher antioxidant activity of the cosmetic cream compared to the oil alone may also be attributed to the inclusion of astaxanthin in the formulation.

The cream, based on the combination of the three vegetable oils, exhibited the second strongest antioxidant activity, as determined by both methods: DPPH analysis (93.38 μmol TE/100 g) and FRAP analysis (120.40 μmol TE/100 g). The results obtained suggest that the presence of different classes of antioxidant compounds within the blended oils, such as polyphenols and tocopherols, provides a complementary effect that enhances both radical scavenging activity and metal-reducing ability in the tested sample. Similar complementary actions of polyphenols and tocopherols have been described in oils rich in polyunsaturated fatty acids. There are interactions between alpha-tocopherol and linoleic acid (in Chaenomeles japonica seed oil, Prunus armeniaca kernel oil), on the one hand, and between γ-tocopherol and alpha-linolenic acid (in Rosa canina seed oil), on the other hand [49]. Superior antioxidant activity was also reported in a study by Kunik et al. [50], developing an emulsion based on a mixture of vegetable oils (linseed, wheat germ, sesame, mustard, and pumpkin) compared to a formulation containing solely mineral oil.

The obtained higher antioxidant values of the developed creams compared to pure oils may be related to the formulation constituents, particularly the presence of astaxanthin. Being a potent lipophilic antioxidant, astaxanthin may complementarily interact with tocopherols present in the oils. Astaxanthin can efficiently quench the singlet oxygen and lipid peroxyl radicals, while tocopherols can interrupt the propagation step of lipid peroxidation by donating hydrogen atoms. This dual action may result in a cumulative increase in the total antioxidant capacity. Furthermore, the presence of sericin, a hydrophilic silk protein rich in hydroxyl and amino groups, could also contribute to the regeneration or stabilization of lipid-phase antioxidants at the oil–water interface, enhancing their effectiveness.

For the sake of clarity, the antioxidant extraction efficiency and the potential interference of formulation excipients should also be noted. The extraction efficiency of the tested creams is influenced by the polarity of the solvent, as well as the physicochemical properties of the constituents. In this regard, the selected solvent (70% ethanol) is characterized by good extracting properties for a wide variety of phytocompounds [51]; however, incomplete extraction of certain antioxidants cannot be excluded. The latter may also be influenced by the constituents of Neofin Nat (cetearyl alcohol, polyglyceryl-3 stearate, and caprylic/capric triglycerides), which may form a structured lipid matrix that encompasses the lipophilic antioxidants (e.g., tocopherol) and restricts their diffusion in the extraction solvent. Similarly, the phenolic compounds present in the vegetable oils may remain partially associated with the oil phase, resulting in lower apparent antioxidant recovery. The effect of the emulsifying base Neofin Nat may also be exerted in the opposite (positive) direction, due to the presence of shea butter and beeswax, and the contained vitamins (A, E) and flavonoids. Regarding the effect of phenoxyethanol, its phenolic structure suggests potential radical scavenging activity, which may positively influence the results of the DPPH assay. Conversely, its low reducing power in the FRAP test implies insignificant interference.

The obtained results revealed the feasibility of both Japanese quince oil (C1) and mixed oils (C4)—based models as antioxidant cosmetic creams. The differences in their rheological behavior suggest the plausible applicability of Japanese quince oil cream as a daycare antioxidant cream, whereas the mixed oils-based cream (C4) model may potentially serve as a night cream for restorative and antioxidant care.

4. Conclusions

A series of cosmetic creams was prepared to evaluate the effect of the vegetable oil phase on their spreadability, rheological behavior, and antioxidant activity. All elaborated creams are non-Newtonian fluids, exhibiting pseudoplastic behavior. Based on the results from the conducted studies, two optimal model cosmetic creams were derived—the formulation based on Japanese quince seed oil with the highest antioxidant activity and spreadability, which suggests its suitability as a daycare cosmetic cream and the model based on the mixture of oils which is characterized by most suitable from rheological point of view consistency along with high enough antioxidant activity. The combined formulation exhibited suitable strength and low spreadability values, which would contribute to sufficient residence time on the skin and suggest its possible application as a night restorative antioxidant cream. Subsequent research will focus on sensory evaluation and in vitro skin permeation studies to further confirm the cosmetic potential of the developed formulations.