Abstract−− In this research, the strawberries of ‘Albion’ and ‘Festival’ species were used for the determination of the physical and chemical properties of strawberry seeds and seed oils. According to the result of the research, the free fatty acidity, peroxide number, iodine number, saponification and unsaponifiable matter number, tocopherol and total phenol quantity of ‘Albion’ and ‘Festival’ strawberry seed oils were determined as 0.87 – 1.08 KOH g/kg, 15.2 – 17.6 meqO₂/kg, 157.22 – 189.69, 123.79 – 169.95 mg KOH/g, 0.27 – 1.09%, 48.42 – 50.02 mg/100 g, 1.54 – 1.37 mg/100 g, respectively. When the fatty acids composition strawberry seed oils were examined, oleic, linoleic and linolenic fatty acids were determined as the dominant fatty acids. In terms of the sterol composition, especially, Σ-beta sitosterol was determined at high level among them. In terms of the mineral matters, Na, Mg, Al, Si, P, K, Ca, Cr, Mn, Ni, Cu, Zn, Se, Sr, Pd, Ba and Pt mineral matters were found out in ‘Albion’ and ‘Festival’ strawberry seed oils. It was determined that the oils derived from ‘Albion’ and ‘Festival’ strawberry seeds are processable in terms of vegetable oil technology and have functional feature in terms of α-tocopherol, total phenol, fatty acids composition, sterol composition and mineral matter composition that they contain.

Keywords−− Strawberry, Seeds, Oil, Instrumental characterization, fatty acids, sterols,mineral matters

I. INTRODUCTION

Strawberry (Fragaria) is a plant species which is a member of the Rosaceae familia and is a poly fruit consisting of many small fruits embedded into the floral receptable. Strawberry is a poly fruit consisting of many small mono fruits embeded into the flesh. The brownish and whitish stains on the fruit contain the seeds of strawberry (Parrucci and Eubanks, 1997). It was composed of 23 species that are growing up in the area extending from the Northern sphere and South America to Hawaii (Darrow, 1966).

In general, the nutritional values of strawberry (100 g) were reported as 37 cal energy, 89.9% water, 8.4 g carbohydrates, 0.7 g protein, 0.5 g fat, 0.5 g ash, 164 mg potassium, 21 mg calcium, 21 mg phosphorus, 1 mg sodium, 1 mg iron, 60 IU vitamin A, 59 mg vitamin C, 0.07 mg riboflavin, 0.6 mg niacin, 0.03 mg thiamine (Kılıçel, 2005). In addition, vitamin C content of the strawberry species (53- 68 mg AA / 100 g fresh weight) was reported. In the content of strawberry, quercetin (8.6 mg/kg) which is known as antioxidant and cancer inhibitor compound, kaempferol (12 mg/kg), p-coumaric acid (14-27 mg/kg), catechin (58.34 mg/kg), gallic acid (1.85 mg/kg), ellagic acid (6.1 mg/kg), caffeic acid (2 mg/kg) and ferulic acid (2 mg/kg) were reported (Aaby et al., 2007; Ekşi Karaağaç and Uçurum, 2019; Yıldız and Baysal, 2003; Muthukumaran et al., 2017).

The strawberry oil which is produced from the seeds that are a by-product as a result of the industrial processing of strawberries has become a new example for the untraditional vegetable oils. In a few researches on this matter, it was reported that the strawberry seed oil is highly composed of poly unsaturated fatty acids (78% of the fat), these poly unsaturated fatty acids are significantly composed of α-linolenic acid (42.22 g/100 g), and apart from this, they have an appropriate omega-6: omega-3 ratio content (n-6/n-3: 1,16 g/100g) and have a different fatty acid profile (van Hoed et al., 2009). Furthermore, it was reported that the strawberry seed oil also contains p-Coumaric acid (4340-6630 mg/kg), Ferulic acid (9.3-11.6 mg/kg), Tyrosol (2400.8-10730.2 mg/kg), Homovanillic acid (3.6-4.5 mg/kg), Vanillic acid (60.2-130.2 mg/kg), Vanillin (530.1-660.8 mg/kg) bioactive phenolic compounds. It was also reported that the strawberry seed oil is a rich tocopherol (560.0-587.8 mg/kg) and antioxidant source (total phenolic content 9.3-10.4 mg/g, FRAP 0.24-0.30 mmol/L g oil). It was determined that the strawberry seed oil has a one-year shelf life when it is stored properly (van Hoed et al., 2011).

As it is seen in the literature reviews, the studies that have been carried out so far generally focused on the composition of strawberry, its physico-chemical properties and its effects on health and, in this study differently from the literature, the physico-chemical properties of the seed oils of two different (‘Festival’ and ‘Albion’) strawberry species which were collected from the Mediterranean and Central Anatolia regions were determined in terms of vegetable oil technology and functionality.

II. MATERIAL AND METHOD

A. Material

Derivation of Strawberry Seeds

Strawberry seeds were derived from ‘Festival’ and ‘Albion’ species strawberries. ‘Albion’ species strawberries are field strawberry and were collected from Akşehir district of Konya province in Turkey in August and ‘Festival’ species strawberries, on the other hand, are greenhouse strawberry and were collected from Serik district of Antalya province in August. The strawberries of both species were supplied from certified producers. At the initial stage of the seeds derivation, the outer parts where the strawberry seeds are present were stripped by means of a special knife. ‘Albion’ and ‘Festival’ species strawberry seeds were dried by natural means in shadow in August. The drying periods varied between 3-4 days (22-25 °C). The dried strawberry was slightly scraped from the shell parts with a spatula and the seeds were separated. In total, 120 kg fruits from ‘Albion’ species were dried and 80 kg fruits from ‘Festival’ species were dried. 7.58 g seeds were derived from 1 kg of ‘Albion’ species strawberry and 5.62 g seeds were derived from 1 kilogram of ‘Festival’ species strawberry. The dried strawberry seeds derived were put into cloth bags and kept for the analyses in a dry and cool (15 °C) environment and the analyses specified in the method section were applied.

B. Method

Proximate Analyses made in Strawberry Seeds

In the strawberry seeds, the analyses of dry matter number, ash assessment, foreign matter number, one thousand particles weight, size and fat quantity were carried out according to their methods (AOAC, 2000).

Proximate Analyses made in Strawberry Seeds Oils

In the strawberry seeds oils, the analyses of free fatty acidity, peroxide number, iodine number, color assessment, saponification number assessment, unsaponifiable matter number were carried out according to the methods of AOCS Ca-5a-40, Cd 8-53, Cd1-21, Cc 13c-50, Cd3-25, Ca6a-40, respectively (AOCS, 1990).

Tocopherol Analysis

Tocopherol quantities were determined by reading at HPLC by using the analysis method developed by Arnaud et al. (1991).

Total Phenolic Matter Quantity Analysis

For the total phenol analysis of the strawberry seeds oils, Folin-Ciocalteu method was preferred. Within the scope of the analysis, Folin-Ciocalteu method which had been previously applied by Toor and Savage (2006) was used. Gallic acid was used as standard. 200 μl extract solution was diluted in compliance with the method, mixed with 1,5 ml Folin-Ciocalteu reagent diluted by 10 times, added with 1.2 mL 7.5 % (w/v) Na₂CO₃ solution and finally the tubes were mixed in vortex. The values of the samples were read with spectrophotometer at the wave length of 760 nm. The total phenolic matter quantity was given as mg GAE/100 g.

Fatty Acids Composition

In line with the method specified in AOCS, the fatty acid composition of the strawberry seed oils was made by using SHIMADZU GC-2025 brand gas chromatography. The fatty acid methyl esters prepared by treating the fats by n-Heptane and potassium hydroxide were determined by gas chromatography (AOCS, 1990).

The column used is at the length of 60 m, at the diameter of 0.25 mm and at the film thickness of 0.20 μm and is of RTX-2330 brand. The operating conditions of GC are given below.

Temperatures

Column : 180 °C

Injection : 200 °C

Detector : 200 °C

Flow rates

Carrying gas (N₂) : 30 ml/min.

Combustible gas (H₂) : 28 ml/min.

Dry air : 220 ml/min.

Injection amount : 1 μl

Mineral Matter Analysis

0,5 gram fat was put into the combustion container and 15 g/mL pure HNO₃ was added onto it. It was burned in MARS 5 microwave oven at 200 ^oC. The solution was diluted to 100 gml with ultra-pure water and filtered through ashless filter paper (Macherey-Nagel MN 640w, black-tape, 110 mm diameter). The concentrations of the mineral matters were determined by reading the prepared samples in ICP-AES (Inductively Coupled Plasma Atomic Emission Spectrometer) device (Skujins, 1998).

Sterol Composition

1.5 g fat sample was weighed and cholesterol standard (0.1 %) dissolved in 2 ml chloroform was added. Then, chloroform was evaporated in rotating evaporator. 10 ml ethanol and 6 ml 6 M KOH were added and held in oil bath 90 °C for 1.5 h for saponification. The unsaponifiable part was extracted with hexane. After evaporating hexane, 0.25 ml pyridine and 0.3 ml BSTFA (N,O-Bis(trimethylsilyl)trifluoroacetamide) were added and derivatized in the drying oven at 80 °C for 30 minutes. 1 ml GC vialine was taken from the derivatized extract (Tanacı, 2013).

Device : GC-2010 PLUS

Detector : FID

Column : TRB-Sterol (30 m x 0.22 mm x 0.22 um)

Injection Block Temperature : 280 °C

Injection Mode : Split

Flow Control Mode : Pressure

Pressure : 180 kPa

Split Ratio : 50

Column Temperature Program :280 °C 40 min. (Isothermal)

FID Temperature : 300 °C

Statistical Analysis

The data obtained as a result of the research was analyzed by using SPSS (Statistical Package for Social Sciences) program for Windows 22.0. The average standard devia-

tion was used in the assessment of the data as the definitive statistical methods. The One Way Anova Test was used in the comparison of the data among more than two independent groups (Püskülcü and Ikiz 1998).

III. RESULTS AND DISCUSSION

As it is seen in the Table 1, the physical properties of the strawberry seeds, which cover seed weight, size, foreign matter, dry matter, ash and fatty quantities, were determined as 0.66 g, 0.73-0.97 mm, 7.4%, 92.51%, 3.26%, 9.20% in ‘Albion’ species and 0.67 g, 0.67-1.10 mm, 5%, 94.29%, 2.54%, 14.84% in ‘Festival’ species, respectively.

It was reported that the moisture levels of the vegetable seeds must be below 12% (Gökalp, 2001). Kosmala et al. (2015) reported the moisture ratio of strawberry seed as 4.7%, Grzelak-Błaszczyk et al. (2017) reported it as 4% and Pieszka et al. (2015a) reported it as 7,78%. Accordingly, it was found out that the moisture values of ‘Albion’ and ‘Festival’ strawberry seeds were below the critical moisture level. In the previous studies, ash quantity was found as between 3.3 – 3.8% (Grzelak-Błaszczyk et al., 2017), as 3,69 % (Pieszka et al., 2015b), as 3.1 % (Milala et al., 2017) and as 3.61 % (Kosmala et al., 2015). According to the results obtained, it was determined that the ash ratio of ‘Albion’ and ‘Festival’ strawberry seeds (2.5 – 3.2 %) were close to the values determined by the other researchers. In the literature, the oil ratios of the strawberry seeds were reported as 18.56 % (Pieszka et al., 2015a), 18 % (Milala et al., 2017), 6.2 % (Helbig et al., 2008), 11.63 % (Pieszka et al., 2015b) and 7.6 % (Da Silva and Jorge, 2017). Da Silva and Jorge (2017), in the study carried out on the oil ratios of various fruit seeds, reported that the oil ratios of apple, citron, grape, guava, kumquat, mangaba, mango, yellow melon, orange, papaya, passion fruit, pumpkin, graviola, strawberry and tomato seeds vary between 7.0 and 40.4 %.

As it is seen in the Table 2, the free fatty acidity, peroxide number, iodine number, saponification and unsaponifiable matter number, tocopherol and total phenol quantity of the strawberry seed oils were determined as 0.87 %, 15.2 meqO₂/kg, 157.22, 123.79 mg KOH/g, 0.27%, respectively, in ‘Albion’ species strawberry seed oil, and as 1.08 %, 17.6 meqO₂/kg, 189.69, 169.95 mg KOH/g, 1.09%, respectively, in ‘Festival’ species strawberry seed oil.

In the previous studies, the acidity values in the strawberry seed oil were reported as 1.54 mgKOH/g (van Hoed et al., 2009), 3.35 mgKOH/g (Mildner-Szkudlarz et al., 2019), 3,7 mgKOH/g (Sikora et al., 2015) and 2.09 mgKOH/g (Pieszka et al., 2015a). Peroxide number in the strawberry seed oil was reported as 8.78 meq O₂/kg by Pieszka et al. (2015a) and between 2.7 and 25.7 meq O₂/kg by Milala et al. (2017). According to the data of Natural Sourcing (2015), this value varies between 170 and 210, whereas it was reported between 180 – 200 according to the data of The Soap Kitchen (2010). The saponification number was determined as 184.6 mg KOH/g by Sikora et al. (2015). It was determined that the saponification numbers of the strawberry seed oils (123.79 – 169.95 mg KOH/g) are below the values of the saponification numbers found out in the previous studies. The unsaponifiable matter number was determined as 0.5 – 1.5 % in sunflower seed oil, as 0.5 – 1.6 % in soy bean oil and as 0.7 – 1.8 % in canola oil (Karleskind and Wolf, 1996). The unsaponifiable matter numbers in the strawberry seed oils (0.27% in ‘Albion’ and 1.09% in ‘Festival’) were found close to the values of the unsaponifiable matter number of the other seeds. It was determined that the strawberry seed oils have high values in terms of free fatty acidity and peroxide number are included in the drying oils (>130) in terms of iodine number have lower saponification number than sunflower seed oil, olive oil, corn oil and cotton seed oil (178-187) in terms of saponification number and the strawberry seed oils can be a new source for food and industrial use in terms of unsaponifiable matter number. Furthermore, it was also seen that these chemical properties of the strawberry seed oils vary at the level of p<0.05 statistically according to the strawberry species.

As it is seen in the Table 3, L, a and b color values of the strawberry seed oils were determined as 37.22 3.79, 47.48 in ‘Festival’ species strawberry seeds, respectively, whereas these values were found out as 77.46, -3.12, 20.72 in ‘Albion’ species strawberry seeds. The results showed that ‘Albion’ species strawberry seed oil color is darker than ‘Festival’ species (Table 3). van Hoed et al. (2011), in a previous study, analyzed the cold pressed oils before

Table 3. Color determination in strawberry seeds oils.

	L	a	b
*Albion*	77.46±0.88^a	-3.12±0.14^b	20.72±0.77^b
*Festival*	37.22±4.73^b	3.79±1.25^a	47.48±8.70^a

^{a - b} Averages were statistically (at the level of p<0.05) different from each other.

Table 4. Tochopheral and total phenolic matter quantities in strawberry seeds oils.

	Tochopherol quantity (mg/100 g)	Total phenolic matter quantity (mg/100 g)
Albion	48.42±0.44^b	1.54±0.09^a
Festival	50.02±0.36^a	1.37±0.06^b

^{a - b} Averages were statistically (at the level of p<0.05) different from each other.

Table 5. Fatty acids composition in strawberry seeds oils.

Fatty acids (%)	*Albion*	*Festival*
Fatty acids (%)	*Albion*	*Festival*
Miristic	0.06±0.001^a	0.04±0.002^b
Miristoleic	0.02±0.001^a	0.02±0.005^a
Pentadecanoic	4.46±0.004^a	nd
Palmitic	0.16±0.02^b	3.24±0.06^a
Palmitoleic	0.06±0.002^a	0.05±0.001^b
Heptadecanoic	0.07±0.002^a	0.05±0.002^b
Stearic	1.88±0.04^a	1.18±0.002^b
Oleic	32.89±0.01^a	9.62±0.003^b
Linoleic	29.82±0.05^b	47.03±0.13^a
Arachidic	0.09±0.01^a	0.08±0.001^b
Linolenic	29.29±0.004^b	38.17±0.01^a
cis-11-eicosenoic	0.00±0.002^b	0.03±0.002^a
gama-linolenic	0.14±0.01^a	0.02±0.002^b
Heneikosanoic	0.03±0.003^b	0.11±0.002^a
cis-11,14-eikosadienoic	0.21±0.01^a	0.16±0.01^b
Behenic	0.01±0.001^a	nd
cis-8,11,14-eicosatrienoic	nd	0.02±0.01^a
cis-11,14,17-eicosatrienoic	0.10±0.002^a	0.01±0.001^b
Arachidonic	0.09±0.01^a	0.04±0.003^b
cis-13,16-docosadienoic	0.06±0,01^a	0.02±0.001^b
Lignoceric	0.13±0.01^a	0.08±0.001^b
Nervonic	0.43±0.004^a	0.03±0.001^b

^{a - b} Averages were statistically (at the level of p<0.05) different from each other.

nd: Not determinated

and after their filtration, and reported L, a and b values as 50.2, -0.50, 14.43, respectively, before the filtration and as 46.91, -0.61, 12.85, respectively, after the filtration.

As it is seen in the Table 4, α-tocopherol quantities of the strawberry seed oils were found as 49.42 mg/100 g in ‘Albion’ species and 50.02 mg/100 g in ‘Festival’ species, and the total phenol quantities were found as 1.54 mg/100 g in ‘Albion’ species and as 1.37 mg/100 g in ‘Festival’. In the previous researches, the tocopherol quantity of the strawberry seed oil was reported as 86.33 mg/100 g (Silva et al. 2017), 58.4 mg/100 g (Pieszka et al., 2015a) and 280.3 mg/100 g (van Hoed et al., 2009). In another research, Milala et al. (2017) found out that the tocopherol quantity in the

Table 6. Sterol composition in strawberry seeds oils.

Sterol composition	*Albion*	*Festival*
Cholesterol (%)	0.36±0.003^a	0.18±0.002^b
Brassikasterol (%)	nd	nd
Kampesterol (%)	5.58±0.001^a	3.92±0.002^b
Stigmasterol (%)	2.76±0,007^a	1.23±0.003^b
Σ-Beta Sitosterol (%)	88.06±0.006^b	91.58±0.005^a
∆5,24-Stigmastadienol (%)	nd	0.13±0.002^a
∆7-Stigmastenol (%)	nd	0.11±0.001^a
∆7-Avenastenol (%)	3.23±0.003^a	2.84±0.004^b

^{a - b} Averages were statistically (at the level of p<0.05) different from each other.

Nd: Not determinated

strawberry seed oil varies between 83.9 and 543.6 mg/kg. According to these results, it is seen that the strawberry seed oils can be a new source for food and industrial use in terms of α-tocopherol and total phenolic matter quantities.

In the Table 5, when the fatty acids composition of strawberry seed oils was examined, oleic acid was determined as 32.886%, linoleic acid as 29.822% and linolenic as 29.294% at the highest ratios in ‘Albion’ species strawberry seed oil and linoleic was determined as 47.029% and linolenic as 38.171% in ‘Festival’ species. Pieszka et al. (2015b) found the oleic acid quantity as 17.6%, linoleic acid as 48.88%, linolenic acid as 5.55%, Helbig et al. (2008) found the oleic acid quantity as 19.91%, linoleic as 36.19%, linolenic as 28.18%, Milala et al. (2017) found the oleic acid quantity between 15 – 17.2%, linoleic between 48.7 – 47.9% and linolenic between 31,7 – 297 %. Kafkas et al. (2009) in the study carried out on 9 strawberry species found the highest and lowest acid contents of oleic, linoleic and linolenic acid quantities as 16.96% (Kabarla) – 28.48% (Whitney), 31.17 % (Fern) – 40.62 % (Gianna), 22.35% (Gianna) – 36.67 % (Kabarla), respectively. It was reported that the strawberry seed fatty acids composition will be useful specifically in the prevention of metabolic diseases (Pieszka et al., 2015a).

As it is seen in the Table 6, when the phytochemical sterol composition of the strawberry seed oils was examined, the sterol which was found at the highest ratio in the strawberry seed oils is Beta-Sitosterol and this value was determined as 88.064% in ‘Albion’ species and as 91.582% in ‘Festival’ species. In the literature, Beta-Sitosterol values were found as 2987.5 mg/kg (93.39%) (da Silva and Jorge, 2017), 2656.6 mg/kg (79.49%) (Pieszka et al., 2015a) and 356.65 mg/100 g (65.71%) (Mildner-Szkudlarz et al., 2019) in the strawberry seed oil in the studies carried out. In a study performed, the sterol composition of blackberry, blueberry, cornelian cherry, strawberry, red raspberry and kiwi seeds oils was examined and the highest sterol in all fruits was determined as Beta-sterol. These values were reported as 84.7% in blackberry, 66.5% in blueberry, 60.4 % in cornelian cherry, 59.1 % in kiwi, 79.6 % in raspberry and 71.1% in strawberry (van Hoed et al., 2009). According to these

Table 7. Mineral matter analysis of strawberry seeds oils.

Mineral Matter (ppm)	*Albion*	*Festival*
Mineral Matter (ppm)	*Albion*	*Festival*
Na	38.35±3.00^b	43.45±1.83^a
Mg	5.79±2.05^b	6.66±0.28^a
Al	0.42±0.93^b	0.54±0.19^a
Si	43.56±2.94^a	38.92±2.96^b
P	101.83±1.04^b	114.44±4.62^a
K	11.99±0.91^a	6.06±1.83^b
Ca	2.38±2.51^b	2.94±2.27^a
Cr	0.03±1.24^b	0.06±0.74^a
Mn	0.38±1.29^b	0.82±2.09^a
Fe	<0.00^b	0.60±1.78^a
Ni	0.10±0.39^a	0.05±1.22^b
Cu	0.36±0.29^a	0.01±0.03^b
Zn	1.04±1.30^a	1.00±1.60^b
Sr	0.02±0.05^a	0.02±0.16^b
Pd	0.02±0.02^a	0.00±0.03^b
Cd	<0.00^b	0.55±0.98^a
In	0.02±0.03^a	<0.00^b
Sn	5.34±0.26^a	<0.00^b
Ba	0.07±0.81^a	0.04±0.65^b

^{a
- b} Averages were statistically (at the level of p<0.05) different from each other.

results, it is seen that the strawberry seed oils can be a new source for food and health in terms of sterol composition.

As it is seen in the Table 7, when the mineral matter composition of the strawberry seed oils was examined, the sodium (Na) (‘Albion’ 38.35 ppm, ‘Festival’ 43.45 ppm) and silicium (Si) (‘Albion’ 43,56 ppm, ‘Festival’ 38.92 ppm) quantities were found at higher values than phosphorus whereas phosphorus (P) was determined at the highest ratio (‘Albion’ 101.83 ppm, ‘Festival’ 114.44 ppm) in both strawberry species in strawberry seed oils. It was found out that V (0.000042 ppm), Rb (0.000135 ppm), In (0.023729 ppm) and Sn (5.34 ppm) minerals weren’t exist in ‘Festival’ species whereas they exist in the strawberry seed oil of ‘Albion’ species. It was found out that Fe (0.60 ppm) and Cd (0.55 ppm) minerals weren’t exist in the strawberry oil of ‘Albion’ species whereas they exist in the strawberry seed oil of ‘Festival’ species. Calcium (Ca) was found at the amount of 2.38 ppm in ‘Albion’ and at the amount of 2.94 ppm in ‘Festival’, and potassium (K) was found at the amount of 11.998 ppm in ‘Albion’ and at the amount of 6.06 ppm in ‘Festival’ (Table 7). In the previous study, Pieszka et al. (2015b) determined Na, K, Ca, O, Mg, Fe, Mn, Zn and Cu values as 38 ppm, 2690 ppm, 3550 ppm, 4570 ppm, 1270 ppm, 371000 ppm, 48000 ppm, 25900 ppm and 8560 ppm, respectively. In general, it is seen that both strawberry seed oil species have a specifically good potential in terms of P, Na, K and Si mineral matters which were significant in terms of vision and neural system besides the mineral matter composition determined. Furthermore, as it is seen in the Table 4-5-6-7, it was also determined that the tocopherol, total phenol quantity, fatty acids, sterol and mineral matter compositions of the seed oils of ‘Albion’ and ‘Festival’ species may vary depending on the strawberry species at the level of p<0.05 statistically.

IV. CONCLUSION AND RECOMMENDATIONS

As a conclusion, it was determined that strawberry seed oil which is widely grown up throughout the world contains essential nutritional values in terms of human health and nutrition. Especially, it was determined that strawberry seed oils have functional properties in terms of unsaturated fat acids, sterol composition, mineral matter composition, tocopherol and phenolic matter quantities that they contain. It was found out that these characteristics of the strawberry seed oil may vary depending on the strawberry species from which the seeds are derived. It is seen that the strawberry seed oils have a great potential in the valuable oils group also for the medication and cosmetics industries as well as the food industry in terms of their phytochemical contents. From this point of view, it is also recommended to carry out the toxicological studies for the internal and external usage of the strawberry seed oils in the future researches.

ACKNOWLEDGEMENT

The authors thanks to the Scientific Research Projects department of Afyon Kocatepe University for their supports provided to the project no 18.Fen.Bil.59.

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Received: January 3, 2022

Sent to Subject Editor: January 26, 2022

Accepted: March 29, 2022

Recommended by Subject Editor Laura Briand

		Seed weight (g)	Size (mm)		Foreign matter (%)	Dry matter (%)	Ash (%)	Fat (%)
		Seed weight (g)	width	height	Foreign matter (%)	Dry matter (%)	Ash (%)	Fat (%)
*Albion*	0.66±0.01^a		0.73±0.06^a	0.97±0,06^b	7.40±0.29^a	92.51±0.12^b	3.26±0.26^a	9.20±0.48^b
*Festival*	0.67±0.03^a		0.67±0.06^b	1.10±0.10^a	5.00±0.36^b	94.29±0.07^a	2.54±0.23^b	14.84±0.65^a