Antioxidant Effect of Essential Oils of Rosemary, Clove and Cinnamon on Hazelnut and Poppy Oils (1)
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Antioxidant effect of essential oils of rosemary, clove and cinnamon on hazelnut and poppy oils Mehmet Musa Özcan ⇑ , Derya Arslan Department of Food Engineering, Faculty of Agriculture, Selcuk University, 42031 Konya, Turkey article info Article history: Received 26 September 2009 Received in revised form 4 October 2010 Accepted 1 January 2011 Available online 22 January 2011 Keywords: Antioxidant effect Spice Essential oil Hazelnut oil Poppy oil abstract Antioxidant effects of essential oils from rosemary (Rosmarinus officinalis), clove (Syzygium aromaticum) and cinnamon (Cinnamomum zeylanicum) were determined on hazelnut and poppy oils. These essential oils were added to the oils at concentrations of 0.25% and 0.5%. Butylated hydroxyanisole (BHA) at 0.02% level served as standard besides the control groups for comparison. The samples were stored 50 °C in darkness for 14 days. The antioxidant activity of the essential oils was determined by measuring peroxide values (meq O 2 /kg oil) at regular intervals. On the basis of peroxide value assay, the essential oils showed stronger antioxidant effect when compared to control groups. BHA was more effective than the essential oils, whilst it exhibited no antioxidative effect on the first few days of storage. Amongst the investigated essential oils, the cinnamon oil was the most effective on retarding lipid oxidation of crude oils, which was followed by clove and rosemary oils. Ó 2011 Published by Elsevier Ltd. 1. Introduction Antioxidants commonly used in food products today are butyl- ated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT). In recent years the safety of synthetic food additives, including the possible toxicity of these chemicals used as antioxidants has re- ceived increasing attention. So, there is need for other components to act as antioxidants and to render food products safer for man- kind (Branen, 1975; Kahl & Kappus, 1993). As it is known, mainly the edible oils, fats and fatty foods can undergo deterioration in the course of the time depending on external factors such as heat, light, enzyme and trace metals. As a result of autoxidation espe- cially which occurs with the effect of oxygen in the air, unpleasant taste and smell that are known as the signs of rancidity in oil occur. Autoxidation is an irreversible reaction which goes on spontane- ously when it begins, and its rate is directly related to the oil’s unsaturation degree. The breakdown products formed after oxida- tion process such as peroxides, aldehydes and ketones shorten the shelf life of oils and turn products unacceptable for consumption (Akgül, 1989; Shahidi & Nazck, 1995). As a conclusion of these researches, in order to overcome the stability problems of oils and fats synthetic antioxidants, most of which have phenolic characteristic, such as BHA, BHT, ter-butyl hydroquinone (TBHQ) and gallates have been used as food addi- tives for many years (Akgül, 1989; De Man, 1980). But recent re- ports reveal that these compounds may be implicated in many health risks (Özcan & Akgül, 1995). For example, BHT causes liver expansion (Akgül, 1989). Also, it is well known that these com- pounds cause unpleasant taste and smells as they easily vaporise and degrade (Akgül, 1989; Özcan & Akgül, 1995). To prevent these harmful effects of synthetic antioxidants, the use of antioxidants which are found in foods and various natural materials is recom- mended (Özcan & Akgül, 1995). Researches on rosemary show that compounds which have antioxidant characteristic have phenol character and flavonoids occupy an important part in them (Deck- er, 1997). On the other hand, it was reported that eugenol which is found in clove and cinnamon essential oils is an effective antioxi- dant compound in the researches (Farag, Badei, Hewedi, & El- Baroty, 1989a). It is doubtless, this effect is the result of eugenol’s phenolic structure (Weidenbörner, Hindrof, & Tsotsonos, 1990). The antioxidative effects of natural antioxidants on lipids were studied in recent years as a popular research area. Some of the effective factors on the antioxidative mechanism of natural com- pounds on lipids were expressed as the emulsion type of the sys- tem (Frankel, Huang, & Aeschbach, 1997; Hopia, Huang, Schwarz, German, & Frankel 1996), antagonistic and synergistic effects (Medina, Tombo, Satuè-Gracia, German, & Frankel, 2002; Özcan, 1999; Özcan, 2000), temperature (Sature, Huang, & Frankel, 1995), concentration, hydrophilic or the lipophilic tendency of the system (Frankel, Huang, Aeschbach, & Prior, 1996; Schwarz et al., 2000) and the number and the place of connection of the hy- droxyl groups in aromatic cycle (Chen, Chan, Ho, Fung, & Wang, 1996; Das & Pereira, 1990). Overall strongest activity of rosemary was not surprising be- cause of various findings reported on its stabilising effect (Chang, 0308-8146/$ - see front matter Ó 2011 Published by Elsevier Ltd. doi:10.1016/j.foodchem.2011.01.055 ⇑ Corresponding author. Tel.: +90 332 2232933; fax: +90 332 2410108. E-mail address: [email protected] (M.M. Özcan). Food Chemistry 129 (2011) 171–174 Contents lists available at ScienceDirect Food Chemistry journal homepage: www.elsevier.com/locate/foodchem
Transcript of Antioxidant Effect of Essential Oils of Rosemary, Clove and Cinnamon on Hazelnut and Poppy Oils (1)
Food Chemistry 129 (2011) 171–174
Contents lists available at ScienceDirect
Food Chemistry
journal homepage: www.elsevier .com/locate / foodchem
Antioxidant effect of essential oils of rosemary, clove and cinnamon on hazelnutand poppy oils
Mehmet Musa Özcan ⇑, Derya ArslanDepartment of Food Engineering, Faculty of Agriculture, Selcuk University, 42031 Konya, Turkey
a r t i c l e i n f o
Article history:Received 26 September 2009Received in revised form 4 October 2010Accepted 1 January 2011Available online 22 January 2011
Keywords:Antioxidant effectSpiceEssential oilHazelnut oilPoppy oil
0308-8146/$ - see front matter � 2011 Published bydoi:10.1016/j.foodchem.2011.01.055
⇑ Corresponding author. Tel.: +90 332 2232933; faxE-mail address: [email protected] (M.M. Özca
a b s t r a c t
Antioxidant effects of essential oils from rosemary (Rosmarinus officinalis), clove (Syzygium aromaticum)and cinnamon (Cinnamomum zeylanicum) were determined on hazelnut and poppy oils. These essentialoils were added to the oils at concentrations of 0.25% and 0.5%. Butylated hydroxyanisole (BHA) at0.02% level served as standard besides the control groups for comparison. The samples were stored50 �C in darkness for 14 days. The antioxidant activity of the essential oils was determined by measuringperoxide values (meq O2/kg oil) at regular intervals. On the basis of peroxide value assay, the essentialoils showed stronger antioxidant effect when compared to control groups. BHA was more effective thanthe essential oils, whilst it exhibited no antioxidative effect on the first few days of storage. Amongst theinvestigated essential oils, the cinnamon oil was the most effective on retarding lipid oxidation of crudeoils, which was followed by clove and rosemary oils.
� 2011 Published by Elsevier Ltd.
1. Introduction
Antioxidants commonly used in food products today are butyl-ated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT). Inrecent years the safety of synthetic food additives, including thepossible toxicity of these chemicals used as antioxidants has re-ceived increasing attention. So, there is need for other componentsto act as antioxidants and to render food products safer for man-kind (Branen, 1975; Kahl & Kappus, 1993). As it is known, mainlythe edible oils, fats and fatty foods can undergo deterioration inthe course of the time depending on external factors such as heat,light, enzyme and trace metals. As a result of autoxidation espe-cially which occurs with the effect of oxygen in the air, unpleasanttaste and smell that are known as the signs of rancidity in oil occur.Autoxidation is an irreversible reaction which goes on spontane-ously when it begins, and its rate is directly related to the oil’sunsaturation degree. The breakdown products formed after oxida-tion process such as peroxides, aldehydes and ketones shorten theshelf life of oils and turn products unacceptable for consumption(Akgül, 1989; Shahidi & Nazck, 1995).
As a conclusion of these researches, in order to overcome thestability problems of oils and fats synthetic antioxidants, most ofwhich have phenolic characteristic, such as BHA, BHT, ter-butylhydroquinone (TBHQ) and gallates have been used as food addi-tives for many years (Akgül, 1989; De Man, 1980). But recent re-ports reveal that these compounds may be implicated in many
Elsevier Ltd.
: +90 332 2410108.n).
health risks (Özcan & Akgül, 1995). For example, BHT causes liverexpansion (Akgül, 1989). Also, it is well known that these com-pounds cause unpleasant taste and smells as they easily vaporiseand degrade (Akgül, 1989; Özcan & Akgül, 1995). To prevent theseharmful effects of synthetic antioxidants, the use of antioxidantswhich are found in foods and various natural materials is recom-mended (Özcan & Akgül, 1995). Researches on rosemary show thatcompounds which have antioxidant characteristic have phenolcharacter and flavonoids occupy an important part in them (Deck-er, 1997). On the other hand, it was reported that eugenol which isfound in clove and cinnamon essential oils is an effective antioxi-dant compound in the researches (Farag, Badei, Hewedi, & El-Baroty, 1989a). It is doubtless, this effect is the result of eugenol’sphenolic structure (Weidenbörner, Hindrof, & Tsotsonos, 1990).The antioxidative effects of natural antioxidants on lipids werestudied in recent years as a popular research area. Some of theeffective factors on the antioxidative mechanism of natural com-pounds on lipids were expressed as the emulsion type of the sys-tem (Frankel, Huang, & Aeschbach, 1997; Hopia, Huang, Schwarz,German, & Frankel 1996), antagonistic and synergistic effects(Medina, Tombo, Satuè-Gracia, German, & Frankel, 2002; Özcan,1999; Özcan, 2000), temperature (Sature, Huang, & Frankel,1995), concentration, hydrophilic or the lipophilic tendency ofthe system (Frankel, Huang, Aeschbach, & Prior, 1996; Schwarzet al., 2000) and the number and the place of connection of the hy-droxyl groups in aromatic cycle (Chen, Chan, Ho, Fung, & Wang,1996; Das & Pereira, 1990).
Overall strongest activity of rosemary was not surprising be-cause of various findings reported on its stabilising effect (Chang,
172 M.M. Özcan, D. Arslan / Food Chemistry 129 (2011) 171–174
Ostric-Matijasvic, & Hsieh, 1977), and related active componentssuch as carnosol, rosmanol, carnosic and ursolic acids etc. (Chen,Sui, & Ho 1992; Houlihan, Ho, & Chang, 1985; Inatoni, Nakatani,& Fuwa, 1983; Wu, Lee, Ho, & Chang, 1982). Kramer (1985) hasidentified eugenol as one of the major antioxidants present inclove. Farag, Badei, and El-Baroty (1989b) reported that clove andthyme essential oils exhibited antioxidant activity in refined cottonseed oil, with clove oil being superior to thyme oil. Little is knownabout the extent to which the spice essential oils may contribute tothe antioxidant activity, although they have been extensivelyexamined for their medicinal, culinary and antimicrobial proper-ties (Akgül, 1993).
Recently, pollution, stress and industrial food consumption in-creased the existence of free radicals. Antioxidants are the mosteffective compounds against free radicals. A lot of studies were car-ried out on antioxidants characteristics of several plants and corre-sponding derivatives such as essential oil and extracts. It isbelieved that detection of natural antioxidant sources and properconsumption of them in daily diet or use of isolated compoundsin clinical practices would be beneficial for healthy life (Farag, Ba-dei, Hewedi, & El-Baroty, 1989a).
The purpose of this work was to determine rosemary, cinna-mon, clove essential oils’ antioxidant effects on hazelnut and pop-py oil stored at 50 �C in darkness.
2. Material and methods
2.1. Plant material
The samples [rosemary (Rosmarinus officinalis) leaves, clove(Syzygium aromaticum) buds and cinnamon (Cinnamomum zeylani-cum) barks] were purchased from local market in Konya in Turkey.The samples were transported in polypropylene bags, and weredried to constant weight in room temperature for analyses.
2.2. Hazelnut and poppy oils
Natural hazelnut and poppy oils without adding any antioxi-dant were kindly supplied by cool press processing. Peroxide val-ues (meq O2/kg oil) of poppy and hazelnut oils were 1.5 and 1.8,respectively, at the beginning of experiment.
2.3. Butylated hydroxyanisole
Synthetic antioxidant (Sigma) was preferred because of its com-mon usage at vegetable oil producing companies to retard theoxidation.
Table 1The effect of rosemary, cinnamon and clove essential oils on the peroxide value (meq O2/
Concentrations (%) Days
3 5
Rosemary 0.25 14.5 ± 1.1a 120.50 11.5 ± 0.9
Cinnamon 0.25 11 ± 0.6 120.50 11.5 ± 1.5 11
Clove 0.25 11 ± 1.20.50 10 ± 0.4 10
BHA 0.02 6 ± 0.2 11Control 9 ± 0.8
a Mean ± standard deviation.
2.4. Preparation of essential oil
Essential oils of the samples were obtained by hydrodistillationmethod. The plant materials (about 100 g) were ground into smallpieces and were placed in a flask (2 L) together with double dis-tilled water (1.5 L). The mixture was boiled for 4 h. The extractwas condensed in cooling vapour to collect the essential oil of eachmaterial. The extracted oil was dried over anhydrous sodium sul-phate. All essential oils were kept at freezing temperature(�18 �C) until used for the analysis.
2.5. Antioxidant activity measurement
The rate of oxidation was monitored by periodic determinationof peroxide values of the oil stored at 50 �C by using essential oils.A calculated quantity of the BHA and essential oils were added di-rectly to the hazelnut and poppy oils at room temperature with theconcentrations of 0.02%, 0.025% and 0.50% and dissolution was ob-tained by manual homogenisation for about 5 minutes.
A control sample was prepared under the same conditions with-out addition of any antioxidant. Fifteen grams of each sample werestored in 10 � 100 mm open beakers at 50 �C in the dark. For thedetermination of peroxide number, a given weight of hazelnutand poppy oils were dissolved in a mixture of acetic acid:chloro-form (CH3COOH:CHCl3) (3:2,v/v), and saturated solution of KI(1 mL) was then added. The liberated iodine was titrated with so-dium thiosulphate solution (0.01 N) in the presence of starch as anindicator (AOCS, 1990).
2.6. Statistical analyses
Statistical analyses were performed using a one-way analysis ofvariance. A probability value of P < 0.05 was considered significant(Püskülcü & _Ikiz, 1989).
3. Results and discussion
Antioxidant effects of the spice essential oils on hazelnut andpoppy oils were given in Tables 1 and 2. On the third day of the as-say, all the oils showed antioxidant effect in varying degrees onhazelnut oil. Antioxidant activities of rosemary, clove and cinna-mon oils were slightly weaker when compared to BHA added sam-ples. A clear antioxidant effect of the essential oils was notobserved on both hazelnut and poppy oils until the 10th day ofstorage when it is compared to control samples (Tables 1 and 2).After the 10th day, essential oil showed antioxidant effect at vari-ous degrees (Fig 1.). On the other hand, antioxidant effect increasedtogether with essential oil concentration. After 10 days, 0.5% levelof all essential oils on hazelnut oil maintained their antioxidantactivity, exhibiting a marked effect in comparison with BHA (Table
kg oil) of hazelnut oil stored at 50 �C in darkness.
7 10 14
.5 ± 1.2 18.5 ± 1.3 57.5 ± 2.6 80 ± 4.315 ± 1.4 22 ± 2.1 25 ± 1.7 75 ± 4.8.5 ± 0.9 22.5 ± 2.3 25 ± 0.9 47 ± 3.7.5 ± 1.1 19.5 ± 1.7 38.5 ± 2.1 40 ± 2.1
12 ± 1.3 23 ± 1.8 50 ± 3.2 38.7 ± 2.8.5 ± 1.4 14.5 ± 1.2 19 ± 1.8 60 ± 3.8.5 ± 1.3 15.5 ± 0.9 24 ± 1.4 26 ± 2.4
14 ± 1.2 20.5 ± 0.7 35 ± 4.2 85 ± 4.2
(a)
0
10
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30
40
50
60
70
80
90
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
days
per
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e va
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O2/
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il)
Rosemary 0.25% Rosemary 0.50% Cinnamon 0.25% Cinnamon 0.50%
Clove 0.25% Clove 0.50% BHA 0.02% Control
(b)
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900
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15days
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Fig. 1. The effect of rosemary, cinnamon and clove essential oils on the peroxide value (meq O2/kg oil) of hazelnut (a) and poppy (b) oils stored at 50 �C in darkness.
Table 2The effect of rosemary, cinnamon and clove essential oils on the peroxide value (meq O2/kg oil) of poppy oil stored at 50 �C in darkness.
Concentrations (%) Days
3 5 7 10 14
Rosemary 0.25 18.5 ± 1.4a 31.5 ± 4.1 88 ± 6.6 207.5 ± 12.5 537.5 ± 25.30.50 20 ± 2.3 36 ± 3.7 87.5 ± 5.4 332.5 ± 13.7 565 ± 24.6
Cinnamon 0.25 18.5 ± 2.1 30 ± 4.5 62 ± 3.2 231.5 ± 21.6 472 ± 22.10.50 22 ± 4.3 35 ± 3.6 85 ± 4.3 234 ± 21.4 575 ± 17.8
Clove 0.25 19 ± 2.4 34 ± 3.1 78.5 ± 3.7 287.5 ± 27.2 523.5 ± 32.40.50 20.5 ± 1.7 34 ± 2.6 71.5 ± 4.2 305 ± 26.4 552.5 ± 33.2
BHA 0.02 11.5 ± 1.6 19.3 ± 2.1 34 ± 3.1 138 ± 15.3 240 ± 23.8Control 19 ± 3.6 33.5 ± 3.2 76 ± 4.2 413 ± 28.6 812.5 ± 28.4
a Mean ± standard deviation.
M.M. Özcan, D. Arslan / Food Chemistry 129 (2011) 171–174 173
1). As it is seen on Table 1, cinnamon essential oil showed the high-est effect.
When antioxidant effect of essential oils were compared forhazelnut and poppy oils, their effect was more remarkable for pop-py oils (Table 2). Antioxidant effect of 0.5% level of clove oil wasfound higher compared to that of other essential oils (Table 2).The same level of this essential oil was effective on control group,too. The highest antioxidant activity was exhibited by 0.5% concen-tration of clove oil (Fig 1).
All of spice essential oils were effective at 50 �C in comparisonwith control. But when it was compared to BHA, the effect wasat a very limited level.
Farag, Badei, Hewedi, and El-Baroty (1989a) found the antioxi-dant effects of some spice essential oil in linoleic acid which emulsi-fied in aqueous phase following the order like; clove > thyme >rosemary > cumin > sage > frenk cumin. Özcan and Akgül (1995) re-
ported the antioxidant effects of the same spice volatile oils in sunflower oil in their study with an order like: summer savory > rose-mary > sage > marjoram > oregano > anise > tarragon. Lagouri, Ble-kas, Tsimidou, Kokkini, and Boskou (1993) tested four Labiataeplant essential oils and carvacrol and thymol as the main compo-nents of the essential oils from this plant species in lard which wasstored at 35 �C; and they reported that the essential oils and theirmain components showed much higher antioxidant effect thanBHA. Dorman, Peltoketo, Hiltunen, and Tikkanen (2003) determinedthe free radical scavenging activities of the aqueous extracts of O.vulgare L., R. officinalis and S. officinalis obtained from Finland. Theyreported the results as 0.335, 0.236 and 0.265 (IC50 [mg/ml]),respectively.
In bulk corn oil, the rosemary extract, carnosic acid, rosmarinicacid, and a-tocopherol were significantly more active than carno-sol. In contrast, in corn oil-in-water emulsion, the rosemary
174 M.M. Özcan, D. Arslan / Food Chemistry 129 (2011) 171–174
compounds were less active than in bulk oil, and the rosemary ex-tract, carnosic acid, carnosol, and a-tocopherol were more activethan rosmarinic acid (Frankel et al., 1996; Shahidi 1992).
The results obtained in the present study showed that the anti-oxidant activity may be related to the presence of carvacrol, thy-mol and eugenol in essential oils. Cinnamon and clove essentialoils had significantly higher persistent antioxidant activity, proba-bly due to the composition and conditions of the experiment (Far-ag, Badei, Hewedi, & El-Baroty 1989a). Further research is neededon the determination of the correlation between the antioxidantcapacity and the chemical composition of the spice essential oils.
Acknowledgement
This work was supported by Selçuk University, Office of Scien-tific Research Projects (S.Ü.-BAP, Konya-Turkey).
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